Cancer in Patients With Gabapentin (GPRD)

NCT01236053 | Completed Results

• 2 other identifiers: 114790WEUSRTP4931
• Study Type: observational
• Target: 2,323,608
• Locations: 0 countries
• Sites: N/A

Brief Summary

High doses of gabapentin are associated with pancreatic acinar cell tumors in rats, but there has been no post marketing pancreatic carcinogenicity signal with gabapentin as reported by spontaneous reports in AERS or in the published literature. In a published case-control screening study of the association of gabapentin with 55 cancers, the only cancer that met the screening criteria for possibly increased cancer risk with gabapentin exposure was renal (including renal pelvis) cancer. This association was judged to be likely due to or substantially accentuated by confounding by cigarette smoking, hypertension, and lifestyle (Cancer Causes Control 2009;20:1821-1835). The relationship between gabapentin exposure and pancreatic cancer and renal cancer is studied in NCT01138124, and supplemental analyses for these cancers are performed in the current study. The FDA recommended GSK also study the relationship between gabapentin and all-cancer sites, as well as cancer at the following specific sites: 1) stomach, 2) anus, anal canal, and anorectum, 3) lung and bronchus, 4) bones and joints, 5) breast, 6) penis, 7) urinary bladder, and 8) other nervous system. The primary objective of this study is to determine whether exposure to gabapentin is associated with an increased risk of developing all-cancer, and these specific cancers in the United Kingdom (UK) General Practice Research Database (GPRD). Each member of the UK population is registered with a General Practice, which centralizes the medical information not only from the general practitioners themselves but also from specialist referrals and hospital attendances. Over 487 General Practices contribute data to the GPRD. The study cohort from which cases and controls are drawn is all subjects in the GPRD 1993-2008. Gabapentin was approved in the UK in May 1993. Entry into the study cohort begins Jan 1, 1993 for all those who are registered in GPRD before that time, and at the time of registration if later than Jan 1, 1993. Subjects are excluded from the GPRD cohort if they have a cancer diagnosis or a history of cancer prior to the cohort entry date. Patients with a first diagnosis of the respective cancer 1995-2008 are risk set matched with up to 10 controls within the same General Practice for age at cohort entry (within two years), sex, and year of entry into the study cohort (within one year). For cases, the index date is the date of first diagnosis of the respective cancer. The index date for controls is set as the date at which the follow-up time from cohort entry is the same as the case. The index date is chosen so as to give the control equal follow-up time to that of the case for ascertainment of use of gabapentin. Cases and controls will be required to have at least 2 years of follow-up in the study cohort before their index date. Cases must have no history of any other cancer diagnosis prior to the index date. Controls are required to be free of cancer diagnosis in the database up to the control's index date. Data on gabapentin prescriptions are obtained for cases and controls from study cohort entry to the index date. Gabapentin exposure will be assessed as ever/never, number of prescriptions, cumulative dose, and cumulative duration, with a 2 year lag period incorporated to control for protopathic bias (gabapentin prescription for initial pain symptoms of undiagnosed cancer) and latency (time between cancer onset and specific GPRD cancer diagnosis). Crude and adjusted odds ratios and 95% confidence intervals (CI) will be produced from conditional logistic regression models, with additional analyses evaluating for dose-response. Covariates include indications for gabapentin use and risk factors for each cancer.

Conditions

Pain, Neuropathic; Epilepsy; Renal Pelvis Cancer; Pancreatic Cancer; Breast Cancer; Nervous System Cancer; Chronic Pancreatitis; Stomach Cancer; Renal Cell Carcinoma; Diabetes; Bladder Cancer; Bone and Joint Cancer; Penis Cancer; Anal Cancer; Cancer; Renal Cancer

Keywords

renal cancer; pancreatic cancer; epidemiology; renal cell carcinoma; nervous system cancer; lung cancer; breast cancer; case-control; GPRD; Gapabentin; cancer; anal cancer; bone and joint cancer; renal pelvis cancer; penis cancer; stomach cancer; bladder cancer

Outcome Measures

Primary Outcomes (55)

• Number of All-Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incidence of all cancers. Gabapentin Exposure Description: Without 2 year lag = Gabapentin prescription from cohort entry to index date. With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer).

  The case index date was the date of incident cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of All-Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incidence of all cancers. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of All-Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incidence of all cancers. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of All-Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incidence of all cancers. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of All-Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incidence of all cancers. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Stomach Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident stomach cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident stomach cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Stomach Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident stomach cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (1-2 prescriptions \[prescrip\]), T 2 (3-7 prescrip), T 3 (8-298 prescrip). Tertiles without 2 yr lag: T 1 (1-2 prescrip), T 2 (3-7 prescrip), and T 3 (8-388 prescrip). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident stomach cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Stomach Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident stomach cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.01-1.38 months \[mo.\]), T 2 (1.3-5.56 mo.), and T 3 (5.57-105.82 mo.). Tertiles without 2 yr lag: T 1 (0.01-1.38 m.), T 2 (1.39-5.72 mo.), and T 3 (5.73-123.70 mo.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident stomach cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Stomach Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident stomach cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident stomach cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Stomach Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident stomach cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.1-30.0 grams \[g\]), T 2 (30.1-189.0 g), and T 3 (189.1-9600.0 g). Tertiles without 2 yr lag: T 1 (0.1-30.0 g), T 2 (30.1-189.0 g), and T 3 (189.1-11610.0 g). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident stomach cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Anal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident Anal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident anal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Anal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident anal cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (1-2 prescriptions \[prescrip.\]), T 2 (3-7 prescrip.), T 3 (8-298 prescrip.). Tertiles without 2 yr lag: T 1 (1-2 prescrip.), T 2 (3-7 prescrip.), and T 3 (8-388 prescrip.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident anal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Anal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident anal cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.01-1.38 months \[mo.\]), T 2 (1.39-5.56 mo.), and T 3 (5.57 -105.82 mo.). Tertiles without 2 yr lag: T 1 (0.01-1.38 mo.), T 2 (1.39-5.72 mo.), and T 3 (5.73-123.70 mo.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident anal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Anal Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident anal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident anal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Anal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident anal cancer. Gabapentin (Gaba.) Exposure Description: With 2 yr lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.1-30.0 grams \[g\]), T 2 (30.1-189.0 g), and T 3 (189.1-9600.0 g). Tertiles without 2 yr lag: T 1 (0.1-30.0 g), T 2 (30.1-189.0 g), and T 3 (189.1-11610.0 g). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident anal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Lung Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident lung cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident lung cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Lung Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident lung cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident lung cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Lung Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident lung cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident lung cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Lung Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident lung cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident lung cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Lung Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident lung cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident lung cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Bone/Joint Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident bone/joint cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date. Inestimable OR and 95% CI when no gabapentin-exposed cancer cases or no gabapentin-exposed controls at the exposure level.

  The case index date was the date of incident bone/joint cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Bone/Joint Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident bone/joint cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (1-2 prescriptions \[prescrip.\]), T 2 (3-7 prescrip.), T 3 (8-298 prescrip.). Tertiles without 2 yr lag: T 1 (1-2 prescrip.), T 2 (3-7 prescrip.), and T 3 (8-388 prescrip.). Inestimable OR and 95% CI when no gaba.-exposed cases or controls at the exposure level.

  The case index date was the date of incident bone/joint cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Bone/Joint Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident bone/joint cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.01-1.38 months \[mo.\]), T 2 (1.39-5.56 mo.), and T 3 (5.57-105.82 mo.). Tertiles without 2 yr lag: T 1 (0.01-1.38 mo.), T 2 (1.39-5.72 mo.), and T 3 (5.73-123.70 mo.). Inestimable OR and 95% CI when no gaba.-exposed cases or controls at the exposure level.

  The case index date was the date of incident bone/joint cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Bone/Joint Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident bone/joint cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident bone/joint cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Bone/Joint Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident bone/joint cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.1-30.0 grams \[g\]), T 2 (30.1-189.0 g), and T 3 (189.1-9600.0 g). Tertiles without 2 yr lag: T 1 (0.1-30.0 g), T 2 (30.1-189.0 g), and T 3 (189.1-11610.0 g). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident bone/joint cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Breast Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident breast cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident breast cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Breast Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident breast cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident breast cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Breast Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident breast cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident breast cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Breast Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident breast cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident breast cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Breast Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident breast cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident breast cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Penile Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident penile cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident penile cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Penile Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident penile cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (1-2 prescriptions \[prescrip.\]), T 2 (3-7 prescrip.), T 3 (8-298 prescrip.). Tertiles without 2 yr lag: T 1 (1-2 prescrip.), T 2 (3-7 prescrip.), and T 3 (8-388 prescrip.). Inestimable OR/95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident penile cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Penile Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident penile cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.01-1.38 months \[mo.\]), T 2 (1.39-5.56 mo.), and T 3 (5.57-105.82 mo.). Tertiles without 2 yr lag: T 1 (0.01-1.38 mo.), T 2 (1.39-5.72 mo.), and T 3 (5.73-123.70 mo.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident penile cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Penile Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident penile cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident penile cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Penile Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident penile cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.1-30.0 grams \[g\]), T 2 (30.1-189.0 g), and T 3 (189.1-9600.0 g). Tertiles without 2 yr lag: T 1 (0.1-30.0 g), T 2 (30.1-189.0 g), and T 3 (189.1-11610.0 g). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident penile cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Bladder Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident bladder cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident bladder cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Bladder Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident bladder cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident bladder cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Bladder Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident bladder cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident bladder cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Bladder Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident bladder cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident bladder cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Bladder Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident bladder cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident bladder cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case

• Number of Other Nervous System Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident other nervous system cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date. Inestimable OR and 95% CI when no gabapentin-exposed cancer cases or no gabapentin-exposed controls at the exposure level.

  The case index date was the date of incident other nervous system cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his cohort entry was the same as case.

• Number of Other Nervous System (ONS) Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident ONS cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (1-2 prescriptions \[prescrip.\]), T 2 (3-7 prescrip.), T 3 (8-298 prescrip.). Tertiles without 2 yr lag: T 1 (1-2 prescrip.), T 2 (3-7 prescrip.), and T 3 (8-388 prescrip.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident other nervous system cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his cohort entry was same as for case.

• Number of Other Nervous System (ONS) Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident ONS cancer. Gabapentin (Gaba.) Exposure Description: With 2 yr lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.01-1.38 months \[mo.\]), T 2 (1.39-5.56 mo.), and T 3 (5.57-105.82 mo.). Tertiles without 2 yr lag: T 1 (0.01-1.38 mo.), T 2 (1.39-5.72 mo.), and T 3 (5.73-123.70 mo.). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident other nervous system cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was same as for case

• Number of Other Nervous System Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident other nervous system cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident other nervous system cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was same as for case

• Number of Other Nervous System (ONS) Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident ONS cancer. Gabapentin (Gaba.) Exposure Description: With 2 year (yr) lag=Gaba. exposure from cohort entry to 2 yr prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 yr lag=Gaba. exposure from cohort entry to index date. Tertiles (T) with 2 yr lag: T 1 (0.1-30.0 grams \[g\]), T 2 (30.1-189.0 g), and T 3 (189.1-9600.0 g). Tertiles without 2 yr lag: T 1 (0.1-30.0 g), T 2 (30.1-189.0 g), and T 3 (189.1-11610.0 g). Inestimable OR and 95% CI when no gaba.-exposed cancer cases or controls at the exposure level.

  The case index date was the date of incident other nervous system cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was same as for case

• Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident pancreatic cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident pancreatic cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident pancreatic cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident pancreatic cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case

• Number of Pancreatic Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident pancreatic cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Renal Cancer Cases and Matched Controls With the Indicated Exposure to Gabapentin

  Incident renal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin prescription from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin prescription from cohort entry to index date.

  The case index date was the date of incident pancreatic cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as for the case.

• Number of Renal Cancer Cases and Matched Controls With the Indicated Number of Gabapentin Prescriptions

  Incident renal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), Tertile 3 (8-298 prescriptions). Tertiles without 2 year lag: Tertile 1 (1-2 prescriptions), Tertile 2 (3-7 prescriptions), and Tertile 3 (8-388 prescriptions).

  The case index date was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Renal Cancer Cases and Matched Controls With the Indicated Duration of Exposure to Gabapentin

  Incident renal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.56 months), and Tertile 3 (5.57 - 105.82 months). Tertile's without 2 year lag: Tertile 1 (0.01 - 1.38 months), Tertile 2 (1.39 - 5.72 months), and Tertile 3 (5.73 - 123.70 months).

  The case index date was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Renal Cancer Cases and Matched Controls With the Indicated Long Duration of Exposure to Gabapentin

  Incident renal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date.

  The case index date was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

• Number of Renal Cancer Cases and Matched Controls With the Indicated Cumulative Dose of Gabapentin

  Incident renal cancer. Gabapentin Exposure Description: With 2 year lag = Gabapentin exposure from cohort entry to 2 years prior to index date (to control for prediagnostic prescribing for pain symptoms possibly related to cancer). Without 2 year lag = Gabapentin exposure from cohort entry to index date. Tertile's with 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 9600.0 grams). Tertile's without 2 year lag: Tertile 1 (0.1 - 30.0 grams), Tertile 2 (30.1 - 189.0 grams), and Tertile 3 (189.1 - 11610.0 grams).

  The case index date was the date of incident renal cancer diagnosis ascertained in the GPRD study cohort 1995-2008. The matched control index date was the date at which the follow-up time from his/her cohort entry was the same as that for the case.

Study Arms (1)

UK GPRD 1993-2008

The study cohort from which cases and controls are drawn is all subjects in the United Kingdom (UK) General Practice Research Database (GPRD) 1993-2008. Each member of the UK population is registered with a General Practice, which centralizes the medical information not only from the general practitioners themselves but also from specialist referrals and hospital attendances. Over 487 General Practices contribute data to the GPRD. Entry into the study cohort begins Jan 1, 1993 for all those who are registered in GPRD before that time, and at the time of registration if later than Jan 1, 1993. Subjects are excluded from the GPRD cohort if they have a cancer diagnosis or a history of cancer prior to the cohort entry date.

Drug: Gabapentin prescriptions

Interventions

Gabapentin prescriptions DRUG

The exposure of interest is gabapentin use as defined by prescriptions recorded by the GPRD general practitioner (British National Formulry codes). Data on prescriptions for gabapentin will be extracted for each case and control from entry into the study cohort up to two years prior to the index date (the exposure window). A two year lagged exposure is incorporated to account for latency between cancer onset and GPRD diagnosis, and for protopathic bias (gabapentin prescription for initial pain symptoms of undiagnosed cancer). Gabapentin exposure will be parameterized as follows: (1) Ever versus never exposed; (2) Number of prescriptions; (3) Duration of exposure; and (4) Cumulative dose.

UK GPRD 1993-2008

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

The study cohort from which cases and controls are drawn is all subjects in the UK GPRD 1993-2008. Entry into the study cohort begins Jan 1, 1993 for all those who are registered in GPRD before that time, and at the time of registration if later than Jan 1, 1993. Subjects are excluded from the GPRD cohort if they have a cancer diagnosis or a history of cancer prior to the cohort entry date. Follow-up ends Dec 31, 2008, or earlier if the subject leaves the GPRD for any reason including death. There are several advantages to the GPRD dataset for this study. It is a large dataset with detailed longitudinal prescription data, and long term follow-up (mean 7 years) to allow for latency in carcinogenicity. It provides good representation of the elderly who are disproportionately affected by cancer, and routinely includes data recorded by general practitioners on potential risk factors such as smoking, alcohol consumption and body mass index.

You may qualify if:

• The study cohort from which cases and controls are drawn is all subjects in the UK GPRD 1993-2008. Entry into the study cohort begins Jan 1, 1993 for all those who are registered in GPRD before that time, and at the time of registration if later than Jan 1, 1993. Follow-up ends Dec 31, 2008, or earlier if the subject leaves the GPRD for any reason including death.

You may not qualify if:

• Subjects are excluded from the GPRD cohort if they have a cancer diagnosis or a history of cancer prior to the cohort entry date. Cases and controls will be required to have at least 2 years of follow-up in the study cohort before their index date (For cases, the index date is the date of first diagnosis of the respective cancer. The index date for controls is set as the date at which the follow-up time from cohort entry is the same as the case.) Cases must have no history of any other cancer diagnosis prior to the index date. Controls are required to be free of cancer diagnosis in the database up to the control's index date.

Sponsors & Collaborators

• GlaxoSmithKline: lead

MeSH Terms

Conditions

Neuralgia; Epilepsy; Pancreatic Neoplasms; Breast Neoplasms; Nervous System Neoplasms; Pancreatitis, Chronic; Stomach Neoplasms; Carcinoma, Renal Cell; Diabetes Mellitus; Urinary Bladder Neoplasms; Penile Neoplasms; Anus Neoplasms; Neoplasms; Kidney Neoplasms; Lung Neoplasms

Condition Hierarchy (Ancestors)

Peripheral Nervous System Diseases; Neuromuscular Diseases; Nervous System Diseases; Pain; Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Brain Diseases; Central Nervous System Diseases; Digestive System Neoplasms; Neoplasms by Site; Endocrine Gland Neoplasms; Digestive System Diseases; Pancreatic Diseases; Endocrine System Diseases; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Pancreatitis; Chronic Disease; Disease Attributes; Pathologic Processes; Gastrointestinal Neoplasms; Gastrointestinal Diseases; Stomach Diseases; Adenocarcinoma; Carcinoma; Neoplasms, Glandular and Epithelial; Neoplasms by Histologic Type; Urologic Neoplasms; Urogenital Neoplasms; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Kidney Diseases; Urologic Diseases; Male Urogenital Diseases; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Urinary Bladder Diseases; Genital Neoplasms, Male; Genital Diseases, Male; Genital Diseases; Penile Diseases; Rectal Neoplasms; Colorectal Neoplasms; Intestinal Neoplasms; Intestinal Diseases; Anus Diseases; Rectal Diseases; Respiratory Tract Neoplasms; Thoracic Neoplasms; Lung Diseases; Respiratory Tract Diseases

Results Point of Contact

• Title: GSK Response Center
• Organization: GlaxoSmithKline

866-435-7343

Study Officials

• GSK Clinical Trials

  GlaxoSmithKline

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: RETROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 14, 2010
• First Posted: November 8, 2010
• Study Start: June 1, 2010
• Primary Completion: September 1, 2010
• Study Completion: September 1, 2010
• Last Updated: July 6, 2017
• Results First Posted: August 4, 2011

Record last verified: 2017-06