Predictive value of diabetes and impaired fasting glucose to incidence of cardiovascular disease in middle-aged Chinese

Objective To investigate whether diabetes is an independent risk factor for coronary heart disease and stroke in Chinese middle-aged cohort. Methods A cohort of Chinese workers and farmers of Beijing and Guangzhou was baseline surveyed in the fall of 1983-1984 using internationally standardized survey methods under the PRC-USA Collaborative study of Cardiovascular and Cardiopulmonary Epidemiology. From 1991, the cohort was followed-up according to an uniform protocol every two years till the end of 1997. The end points for events of coronary heart disease and stroke were diagnosed according to the MONICA criteria. Baseline fasting blood glucose was stratified according to the 1997 classification of fasting glucose by American Diabetes Association. Age adjusted and multiple risk factor adjusted relative risk of diabetes or impaired fasting glucose(IFG) to CHD or stroke were estimated using Cox regression model. Results There were 9 111 persons in the cohort free of the history of AMI and stroke with complete risk factor data. During 13-year follow-up, 72 cases of coronary events and 259 cases of stroke events emerged. The baseline levels of blood pressure, serum total cholesterol, BMI and smoking rate were higher in diabetes and IFG group compared with those in the normal glucose group. After adjusting for multiple risk factors, the relative risk of diabetes to incidence of coronary heart disease and stroke were 3.38 and 4.20 for women, 3.22 and 2.50 for sex combined group, significantly higher than that of the group with normal fasting glucose, those in men though higher than in normal group but were not statistically significant. There was no significant increase in relative risk in the group with impaired fasting glucose. The relative risk of diabetes to coronary heart disease and stroke was higher than those of high serum cholesterol and smoking but lower than high blood pressure. Conclusion Diabetes is an important risk factor for coronary heart disease and stroke in middle-aged Chinese population.