Pre- and Post-Treatment Investigation of B12 and Folic Acid (Folate) Levels in Patients Receiving Antiepileptic (Anticonvulsant) Treatment for Fibromyalgia: Retrospective Study

NCT07013305 | Completed

• 1 other identifier: 03
• Study Type: observational
• Target: 104
• Locations: 1 country
• Sites: 1

Brief Summary

Fibromyalgia is a rheumatological disorder characterised by chronic widespread body pain, second most common after osteoarthritis. The overall prevalence is 2-8% and it is more common in women. Diffuse body pain, fatigue, sleep and cognitive dysfunction occur. The etiology of fibromyalgia is multifactorial and occurs due to central and peripheral pain mechanisms that occur with neuroendocrine imbalance due to psychological and physical stress in people with genetic predisposition. The diagnostic criteria for fibromyalgia were updated by the American College of Rheumatology in 2016 to include a widespread body pain scale and a symptom severity scale. Fibromyalgia treatment consists of drug (antidepressants and antiepileptics) and non-drug treatments. Pregabalin is also used in the treatment of epilepsy by blocking and modulating the α2 δ subunit of voltage-dependent calcium channels. There are studies showing that antiepileptics cause folate and vitamin B12 deficiency in epilepsy patients. In our study, we aimed to retrospectively investigate vitamin B12 and folic acid levels before and after treatment in patients with fibromyalgia using antiepileptics (anticonvulsants).

Conditions

Vitamin B 12 Deficiency; Folic Acid Deficiency; Fibromyalgia (FM)

Keywords

Antiepileptic (anticonvulsant) drugs; Vitamin D deficiency

Outcome Measures

Primary Outcomes (4)

• Vitamin B12 level analysed before treatment (pre-treatment) (retrospective)

  Vitamin B12 level (pg/mL) among the laboratory parameters analysed before antiepileptic treatment (pre-treatment) for fibromyalgia will be screened retrospectively. Patients who applied to the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia in the last 6 months (June-December 2024) before the ethics committee application date, who were followed up with this diagnosis and started antiepileptic treatment will be screened within 1 month.

  Within 1 month

• Vitamin B12 level analysed after treatment (post-treatment) (retrospective)

  Vitamin B12 level (pg/mL) among the laboratory parameters analysed after antiepileptic treatment (post-treatment) for fibromyalgia will be screened retrospectively. Patients who applied to the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia in the last 6 months (June-December 2024) before the ethics committee application date, who were followed up with this diagnosis and started antiepileptic treatment will be screened within 1 month.

  Within 1 month

• Folic acid level analysed before treatment (pre-treatment) (retrospective)

  Folic acid level (ng/mL), one of the laboratory parameters analysed before antiepileptic treatment for fibromyalgia (pre-treatment), will be screened retrospectively. Patients who applied to the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia in the last 6 months (June-December 2024) before the ethics committee application date, who were followed up with this diagnosis and started antiepileptic treatment will be screened within 1 month.

  Within 1 month

• Folic acid level analysed after treatment (post-treatment) (retrospective)

  Folic acid level (ng/mL), one of the laboratory parameters analysed after antiepileptic treatment for fibromyalgia (post-treatment), will be screened retrospectively. Patients who applied to the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia in the last 6 months (June-December 2024) before the ethics committee application date, who were followed up with this diagnosis and started antiepileptic treatment will be screened within 1 month.

  Within 1 month

Secondary Outcomes (2)

• 25-OH Vitamin D level analysed before treatment (pre-treatment) (retrospective)

  Within 1 month

• 25-OH Vitamin D level analysed after treatment (post-treatment) (retrospective)

  Within 1 month

Eligibility Criteria

• Age: 18 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients who were followed up for 6 months in the physical medicine and rehabilitation clinic with a diagnosis of fibromyalgia and who used antiepileptic (anticonvulsant) drugs will be retrospectively evaluated for the 6 months period (June-December 2024) before the ethics committee approval was obtained. Blood vitamin B12 and folate (folic acid) levels of the patients before and after antiepileptic drug use will be determined. Patients will be evaluated whether there is a change in vitamin B12 and folic acid levels depending on drug use.

You may qualify if:

• Patients aged 18-75 years who have been diagnosed with fibromyalgia, whose vitamin B12 and folic acid levels have been analysed, who do not receive vitamin B12 and folic acid treatment, and who do not have diabetes mellitus, liver and kidney failure

You may not qualify if:

• Patients receiving vitamin B12 and folic acid therapy at the time of antiepileptic (anticonvulsant) drugs initiation, patients with hepatic and renal insufficiency

Sponsors & Collaborators

• Gaziosmanpasa Research and Education Hospital: lead

Study Sites (1)

Gaziosmanpasa Research and Education Hospital

Istanbul, Gaziosmanpasa, 34255, Turkey (Türkiye)

Location

Related Publications (5)

• Mula M, Sander JW. Negative effects of antiepileptic drugs on mood in patients with epilepsy. Drug Saf. 2007;30(7):555-67. doi: 10.2165/00002018-200730070-00001.

  PMID: 17604407 BACKGROUND

• Clauw DJ. Fibromyalgia: a clinical review. JAMA. 2014 Apr 16;311(15):1547-55. doi: 10.1001/jama.2014.3266.

  PMID: 24737367 BACKGROUND

• Talotta R, Bazzichi L, Di Franco M, Casale R, Batticciotto A, Gerardi MC, Sarzi-Puttini P. One year in review 2017: fibromyalgia. Clin Exp Rheumatol. 2017 May-Jun;35 Suppl 105(3):6-12. Epub 2017 Jun 28.

  PMID: 28681712 BACKGROUND

• Aslan K, Bozdemir H, Unsal C, Guvenc B. The effect of antiepileptic drugs on vitamin B12 metabolism. Int J Lab Hematol. 2008 Feb;30(1):26-35. doi: 10.1111/j.1751-553X.2007.00910.x.

  PMID: 18190464 RESULT

• Linnebank M, Moskau S, Semmler A, Widman G, Stoffel-Wagner B, Weller M, Elger CE. Antiepileptic drugs interact with folate and vitamin B12 serum levels. Ann Neurol. 2011 Feb;69(2):352-9. doi: 10.1002/ana.22229. Epub 2011 Jan 19.

  PMID: 21246600 RESULT

MeSH Terms

Conditions

Fibromyalgia; Vitamin B 12 Deficiency; Folic Acid Deficiency; Vitamin D Deficiency

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Neuromuscular Diseases; Nervous System Diseases; Vitamin B Deficiency; Avitaminosis; Deficiency Diseases; Malnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases

Study Design

• Study Type: observational
• Observational Model: CASE CROSSOVER
• Time Perspective: RETROSPECTIVE
• Sponsor Type: OTHER GOV
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: May 21, 2025
• First Posted: June 10, 2025
• Study Start: June 11, 2025
• Primary Completion: June 25, 2025
• Study Completion: July 1, 2025
• Last Updated: January 26, 2026

Record last verified: 2025-05

Locations

TU (1)