Influence of different methods for measuring HbA1c on health checkups in a rural town in Hokkaido, Japan
Using data on health checkups performed in one Japanese town, we investigated the effect on health checkups of the methods used to measure hemoglobin A1c (HbA1c). The study included 337 participants undergoing health checkups at two facilities. At facility 1, HbA1c was measured by high-performance liquid chromatography (HPLC) in 2012 and by immunoassay (IA) in 2013, while at facility 2, HbA1c was measured by HPLC in both years. At facility 1, the mean HbA1c was significantly decreased from 2012 to 2013 (5.83 vs 5.50 %, respectively; P < 0.001), although the mean fasting plasma glucose (FPG) was significantly increased from 2012 to 2013 (91.7 vs 95.2 mg/dL, respectively; P = 0.02). Of the 202 participants at facility 1, 97 who had an HbA1c of ≥5.6 % in 2012 had an HbA1c of <5.6 % in 2013. At facility 2, the mean HbA1c marginally increased, while there were similar FPG levels in both years. An additional study of single blood samples from 27 healthy participants who were tested at the same facility using both HPLC and IA found that the mean HbA1c was significantly lower for IA than for HPLC (5.19 vs 5.50 %, respectively; P < 0.001). In summary, we found a substantial decrease in the mean HbA1c and the prevalence of impaired glucose tolerance and diabetes mellitus in study participants who underwent health checkups for two consecutive years when different methods were used to measure HbA1c. The lack of standardization of HbA1c measurement methods may have a large effect on health checkups.
KeywordsHealth checkup Hemoglobin A1c High-performance liquid chromatography Immunoassay Measurement
- 4.Committee of the Japan Diabetes Society on the Diagnostic Criteria of Diabetes Mellitus. Report of the Committee on the Classification and Diagnostic Criteria of Diabetes Mellitus. J Diabetes Investig. 2010;1:212–28.Google Scholar
- 5.Mizushima S, Tsushita K. New strategy of prevention and control of noncommunicable lifestyle-related diseases focusing on metabolic syndrome in Japan. In: Muto T, Nakahara T, Eun WN, editors. Asian perspectives and evidence on health promotion and education. Tokyo: Springer; 2011. p. 31–9.CrossRefGoogle Scholar
- 6.Ministry of Health, Labour and Welfare of Japan. The basic guideline for health checkups and healthcare advice with a particular focus on the metabolic syndrome (final edition). Tokyo: Ministry of Health, Labour and Welfare of Japan; 2007 (in Japanese).Google Scholar
- 7.Nakanishi K, Ishida A, Mori N, et al. Evaluation of HbA1c by HPLC and immunoturbidimetry latex agglutination on calibrator JCCLS CRM-004a (JDS Lot3). Jpn J Clin Lab Autom JJCLA. 2009;34:233–6.Google Scholar
- 8.National Federation of Industrial Health Organization. An annual report of accuracy control surveillance for clinical laboratory test. http://www.zeneiren.or.jp/research_list/index.html Accessed 28 Sep 2015 (in Japanese).
- 10.Imoto S, Kido T, Nakanishi S, Yamano C. HbA1 assay by auto clinical chemistry analyzer. Annu Rep Kyoto City Inst Health Environ Sci. 2005;71:118–9.Google Scholar
- 12.Ishiguro A, Yamauchi T, Imada R, et al. Differences in hemoglobin A1c (HbA1c) levels due to measurement methods. Igakukensa. 2014;63:767–72 (in Japanese).Google Scholar
- 13.Health and Welfare Statistics Association. 2014/2015 Kokumin Eisei no Doko (Trend for national health and hygiene, Japan). Tokyo: Health and Welfare Statistics Association; 2014 (in Japanese).Google Scholar
- 15.Kashiwagi A, Kasuga M, Araki E, Committee on the Standardization of Diabetes Mellitus-Related Laboratory Testing of Japan Diabetes Society, et al. International clinical harmonization of glycated hemoglobin in Japan: From Japan Diabetes Society to National Glycohemoglobin Standardization Program values. Diabetol Int. 2012;3:8–10.CrossRefGoogle Scholar