Predictors of Diabetes in Older People in Urban China

BACKGROUND China has the largest number of people with diabetes in the world. Over the last 30 years China has experienced rapid economic growth and a growing income gap between rich and poor. The population is ageing, however diabetes in older people has not been well studied to date. In this study we determined incidence and predictors of diabetes in older Chinese people. METHODS During 2001, using a standard interview method, we examined 1,317 adults aged ≥65 years who did not have diabetes in the city of Hefei, and characterized baseline risk factors. Over 7.5 years of follow up, we documented incident diabetes using self-reported doctor diagnosis and the cause of death in the whole cohort, and HbA(1C) ≥48 mmol/mol in a nested case-control sample. A multivariate Cox regression model was employed to investigate risk of diabetes in relation to baseline risk factors. RESULTS During follow up, 119 persons had newly diagnosed diabetes. World age-standardised incidence of diabetes was 24.5 (95% CI 19.5-29.5) per 1,000 person-years. Risk of diabetes was significantly and positively associated with income, waist circumference and body mass index, smoking and uncontrolled hypertension, but negatively associated with having a hobby of walking and frequency of visiting children/other relatives and contacting neighbours/friends. Higher income was significantly associated with increased diabetes risk regardless of cardiovascular and psychosocial risk factors. Compared to those with middle income and no psychosocial risk factors, the hazard ratio for incident diabetes among participants with high income and psychosocial risk was 2.13 (95% CI 1.02-4.45). CONCLUSIONS Increasing incidence of diabetes in relation to high income has become an important public health issue in China. Maintaining social networks and gentle physical activities and reducing psychosocial factors may be integrated into current multi-faceted preventive strategies for curbing the epidemic of diabetes in the older population.