Can HbA1c Replace OGTT for the Diagnosis of Diabetes Mellitus Among Chinese Patients With IFG?

NCT02439684 | Completed

• 1 other identifier: UW 13-299
• Study Type: observational
• Target: 1,357
• Locations: 1 country
• Sites: 3

Brief Summary

This is a cross-sectional study that aims to assess the sensitivity and specificity of using HbA1c as a diagnostic test for detecting the presence of diabetes mellitus (DM) when compared to the use of oral glucose tolerance test (OGTT) among Hong Kong Chinese adult who have impaired fasting glucose (IFG). The investigators will recruit around 1000 non-diabetic adult participants who have impaired fasting glucose (i.e. fasting glucose level between 5.6 to 6.9mmol/L) AND without symptoms of hyperglycaemia to undergo both HbA1c test and oral glucose tolerance test after obtaining their informed consent. A diagnosis of DM is confirmed when both the fasting glucose level and 2-hour-post challenge plasma glucose level fall into diabetic range (i.e. fasting glucose level ≥7.0mmol/L and 2-hour-post challenge plasma glucose level ≥11.1mmol/L) after a standard 75g OGTT. Participants with only 1 plasma glucose value within the diabetic range will be invited to repeat an oral glucose tolerance test for confirmation of their diagnosis as recommended by American Diabetes Association and World Health Organization. Demographic data of the participants including age, gender, smoking status, medical history, diet and activity level will be collected. Lipid profile, blood pressure, waist circumference and body mass index will be checked and the total cardiovascular risk in 10 years will be calculated for each participant using the Joint British Societies 2005 and Framingham 2008 equations to evaluate the baseline cardiovascular risk of the participants. These data will be analyzed using SPSS. The primary outcomes are the sensitivity and specificity of HbA1c in detecting diabetes mellitus diagnosed by oral glucose tolerance test (the gold standard). A receiver operating characteristic (ROC) curve will be obtained by plotting sensitivity against (1-specificity) for each cutoff value for identification of an optimal cutoff point. Diagnostic accuracy will be assessed by the area under the curve (AUC). The differences in characteristics among participants diagnosed to have diabetes mellitus by oral glucose tolerance test or HbA1c will be compared using independent t-test or χ2 test for comparison between the 2 groups.

Conditions

Diabetes Mellitus

Keywords

HbA1c; Diagnostic accuracy; Diabetes Mellitus; Chinese; Impaired fasting glucose

Outcome Measures

Primary Outcomes (2)

• The sensitivity of the use of HbA1c

  The sensitivity of the use of HbA1c at different cut points for diagnosing DM among Chinese adult patients with IFG compared to OGTT as the gold standard.

  around 12-16 weeks after the study completed

• The specificity of the use of HbA1c

  The specificity of the use of HbA1c at different cut points for diagnosing DM among Chinese adult patients with IFG compared to OGTT as the gold standard.

  around 12-16 weeks after the study completed

Secondary Outcomes (5)

• The optimal cut-off level of HbA1c

  around 12-16 weeks after the study completed

• OGTT criteria in Chinese

  around 12-16 weeks after the study completed

• HbA1c criteria in Chinese

  around 12-16 weeks after the study completed

• Cardiovascular risk

  around 24-48 weeks after the study completed

• DM risk

  around 24-48 weeks after the study completed

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

Chinese adult subjects who are classified to have IFG will be recruited from various GOPCs from the Hong Kong West Cluster and New Territories East Cluster.

You may qualify if:

• Aged ≥ 18 year
• Chinese ethnicity
• Diagnosis of impaired fasting glucose (i.e. FG between 5.6-6.9mmol/L) identified from latest blood test results within 18 months prior to recruitment)

You may not qualify if:

• Known history of diabetes mellitus or on hypoglycaemic treatment
• Having symptoms of hyperglycaemia at recruitment
• Women who are pregnant or breast-feeding at recruitment
• Patients taking glucocorticoid at recruitment
• Active and uncontrolled thyroid diseases (including subjects on thyroid replacement therapy or anti-thyroid drugs) or active endocrine diseases such as Cushing's syndrome or Acromegaly at recruitment
• Clinically significant anaemia at recruitment
• Severe renal impairment i.e. eGFR ≤ 30 ml/min/1.73m2
• History of blood donation or blood transfusion within 3 months prior to recruitment

Sponsors & Collaborators

• The University of Hong Kong: lead
• Chinese University of Hong Kong: collaborator

Study Sites (3)

Tsan Yuk Hospital RAMP Clinic

Hong Kong, 852, Hong Kong

Location

Ap Lei Chau General Out-patient Clinic

Hong Kong, Hong Kong

Location

Lek Yuen General Out-patient Clinic

Hong Kong, Hong Kong

Location

Related Publications (2)

• Guo VY, Yu EY, Wong CKh, Sit RW, Wang JH, Ho SY, Lam CL. Validation of a nomogram for predicting regression from impaired fasting glucose to normoglycaemia to facilitate clinical decision making. Fam Pract. 2016 Aug;33(4):401-7. doi: 10.1093/fampra/cmw031. Epub 2016 May 3.

  PMID: 27142313 DERIVED

• Yu EY, Wong CK, Ho SY, Wong SY, Lam CL. Can HbA1c replace OGTT for the diagnosis of diabetes mellitus among Chinese patients with impaired fasting glucose? Fam Pract. 2015 Dec;32(6):631-8. doi: 10.1093/fampra/cmv077. Epub 2015 Oct 14.

  PMID: 26467644 DERIVED

MeSH Terms

Conditions

Diabetes Mellitus

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases

Study Officials

• YU YT Esther, Doctor

  Department of Family Medicine and Primary Care, The University of Hong Kong

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 23, 2015
• First Posted: May 12, 2015
• Study Start: May 1, 2013
• Primary Completion: March 1, 2015
• Study Completion: March 1, 2015
• Last Updated: March 7, 2016

Record last verified: 2016-03

Locations

HK (3)