Diabetic Retinopathy and Chronic Kidney Disease: Associations and Comorbidities in a Large Diabetic Population: The Tongren Health Care Study

Background: Diabetic retinopathy (DR) and chronic kidney disease (CKD) in type 2 diabetes tended to have different pathogenesis, while their distinct risk factors have not been fully investigated. Methods: In the cross-sectional, community-based Tongren Health Care Study, type 2 diabetes was diagnosed based on fasting plasma glucose concentration of ≥7·0 mmol/L or a medical history. DR was assessed using color fundus photograph. CKD was defined by a reduced estimated glomerular filtration rate (eGFR) of <60ml/min/1·73mm 2  and/or albuminuria. Findings: Among the 5103 diabetes patients (8·2%) out of 62,217 participants, the prevalence of DR, reduced eGFR, albuminuria and CKD was 12·8% (95%CI:11·8%,13·7%), 4·6% (95%CI:4·2%,5·1%), 10·1% (95%CI:9·3%,10·9%) and 13·3% (95%CI:12·4%,14·3%), respectively. DR was present in 21·0% of the CKD patients while CKD was detectable in 20·9% of the DR patients. The presence of DR was significantly associated with the CKD and albuminuria (P <0·05), but not with reduced eGFR. Factors independently associated with the presence of CKD instead of DR were older age (P <0·001,OR=1·05), a higher body mass index (P <0·001,OR=1·14), a higher serum concentration of triglycerides (P <0·001,OR=1·26), and a lower blood glucose (P <0·001,OR=0·93). Having hypertension was additionally associated with the presence of reduced eGFR as compared with DR (P=0·005,OR=4·47). Interpretation: Type 2 diabetes patients with older age, higher body mass index, with hypertension and dyslipidemia had a higher chance of being affected by CKD rather than DR, while those with a higher blood glucose level were more prone to DR than CKD. Funding: Beijing Municipal of Health Reform and Development Project #2019-4. Declaration of Interest: None to declare. Ethical Approval: The study protocol was approved by the Medical Ethics Committee of Beijing Tongren Hospital and was in adherence with the Declaration of Helsinki.