Incidence and Risk Factors for Cardiovascular Disease in Diabetic patients in Hong Kong

Abstract

INTRODUCTION Cardiovascular Disease (CVD) is the major cause of morbidity and mortality in patients with diabetes mellitus (DM). The study aimed to calculate the 5-year incidence and identify risk factors for developing CVD in Chinese diabetic patients. METHOD A retrospective cohort study was conducted on 119,276 Chinese adult diabetic patients without CVD history and receiving care in the Hospital Authority primary care clinics on or before 1 January 2009. They were followed up until 31 December 2013. Multiple imputation was used to deal with the missing data. Risk factors including socio-demographics and clinical parameters associated with the incidence of CVD were examined using Cox Proportional Hazard regression. Sensitivity analysis was conducted by using the cohort with complete case. RESULTS Five-year incidence rate (1,000 person-years) of first CVD event (n=9,753) among diabetic patients was 17.6. Risk factors associated with CVD were age (Hazard ratio (HR):1.073), male (HR:1.310), smoker (HR:1.219), longer duration of DM (HR:1.014), insulin used (HR:1.425), higher stage of Chronic Kidney Disease (e.g. stage 5 vs stage 1 HR:4.430) and higher clinical parameters including body mass index (HR:1.022), systolic blood pressure (HR:1.002), total cholesterol to HDL cholesterol ratio (HR:1.056) and Urine Albumin/Creatinine ratio (HR:1.001). All of these risk factors were statistically significant (p <0.05). Sensitivity analysis showed the similar results except insulin use, hemoglobin A1c(HbA1c), systolic blood pressure and Triglyceride. DISCUSSION Identification of CVD-related risk factors and early intervention play a crucial role in preventing CVD complications in diabetic patients. HbA1c, which reflects the control of DM, was not found to be a significant risk factor from this study. Further study is needed to explore the effect of controlling of HbA1c on CVD risk.