Objective: To estimate the incidence rate and effects of risk factors on chronic kidney disease (CKD) in Chinese patients with diabetes, based on Electronic Health Records (EHRs) from the Chinese Electronic health Records Research in Yinzhou (CHERRY) Study.
Methods: Using the CHERRY cohort study with the individual-level information on chronic disease management; and health administrative, clinical and laboratory databases, patients with diabetes without kidney disease at baseline were enrolled and followed up from January 2009 through December 2016. CKD was defined as the estimated glomerular filtration rate(eGFR) <60 mL/(min×1.73 m2) or urine albumin/creatinine ratio (ACR)≥3 mg/mmol. Standardized incidence rates of CKD in diabetic population were calculated according to the 2010 China census data. Cox proportional hazards models were used to explore the association of risk factors on CKD in patients with diabetes.
Results: Over a median 3.2 years of follow-up, 13 829 patients with diabetes were included in this analysis and 1 087 developed CKD. The crude and standardized incidence rate was 23.7(95%CI: 22.3-25.2) and 14.8(95%CI:12.1-17.6) per 1 000 person-years respectively. The incidence rate for developing CKD in patients with diabetes aged over 60 years was higher than those aged 60 and below (26.6 vs. 11.5 per 1 000 person-years, P<0.05). Cox proportional hazards models showed that age over 60 years(HR=1.88, 95%CI: 1.51-2.35), hypertension (HR=1.81, 95%CI: 1.56-2.10), total cholesterol (HR=1.07, 95%CI: 1.00-1.14) and duration of diabetes (HR per year increment=1.02, 95%CI: 1.00-1.03) and the level of high density lipoprotein cholesterol (HDLC, HR=0.49, 95%CI: 0.40-0.61) were significantly associated with CKD. No statistical significance was found for sex, smoking status, alcohol use and average level of fasting glucose (All P>0.05). Subgroup analysis indicated that even when the lipid levels were well-controlled, comorbidity of hypertension was still associated with CKD in the patients with diabetes.
Conclusion: Incidence rate of chronic kidney disease in this Chinese population with diabetes was high. Age and comorbidity of hypertension were the most important risk factors for CKD, suggesting the priority for CKD screening in patients with diabetes in China. Control of blood pressure and lipid were especially crucial to prevent CKD in patients with diabetes.