Five-year outcome of impaired glucose regulation and its risk factors in community residents

Objective To investigate the outcome and risk factors of subjects with impaired glucose regulation (IGR). Methods A total of 192 IGR subjects from a cross-sectional survey in June to August 2002 were followed up for 5 years. Anthropometric measurement and 75 g oral glucose tolerance test were performed. The prevalence of isolated impaired fasting glucose (I-IFG), isolated impaired glucose tolerance (I-IGT), IFG+ IGT, normal glucose tolerance (NGT) and diabetes mellitus (DM) was compared. t test, Chi-square test, and analysis of variance were used for data analysis. Results Five participants died during 5 years’ follow up. Of the rest 187 subjects, 79 were found to develop DM. The annual incidence of DM and NGT was 8.4 % (79/187/5-y)and 6.3%(59/187/5-y), respectively. The annual incidence of DM was 8.2 %(47/114/5-y), 6.3%(12/38/5-y) and 11.4%(20/35/5-y) for the subjects with I-IGT, I-IFG and IFG+ IGT, respectively. The risk of DM was significantly higher in IFG+ IGT subjects than I-IFT subjects. Compared with IGR subjects, those with new DM were characterized with hypertension, obesity, older age, and higher level of body mass index (BMI), waist circumference, waist-to-hip ratio and 2 h postprandial plasma glucose at baseline. BMI and systolic blood pressure during follow up were significantly higher than at baseline in subjects with new DM. Conclusions There might be a different course of I-IFG, I-IGT and IFG+ IGT progressing to DM among community residents, and there is a higher conversion rate in IFG+ IGT subjects. Various metabolic abnormalities can promote IGR progressing to DM. Key words: Impaired glucose regulation; Diabetes mellitus; Epidemiology