AIM:To investigate and analyse the prevalence and risk factors associated with diabetic retinopathy severity in Qingdao.

METHODS: This survey consisted of the 2 following parts: 2859 community residents aged >60 years old and 4275 patients with T2DM who were older than 30 years old in Qingdao. Ophthalmic examinations were performed on all patients. A questionnaire was used to obtain the patient's age and gender, the duration of diabetes mellitus(DM), glycaemic control and their knowledge of diabetic retinopathy(DR). Blood pressure and haemoglobin levels were recorded. All included patients underwent a comprehensive ophthalmic examination that included a fundus examination and retinal photographs and that assigned a grade for the severity of retinopathy according to the Early Treatment Diabetic Retinopathy Study(ETDRS)severity scale. Patients with severe non-proliferative or proliferative diabetic retinopathy and clinically significant macular edema(CSME)required ophthalmic therapy were assigned to the need-treatment group, while the remaining patients with DR were assigned to the need-observation group. Correlation and regression analyses were performed to determine the required-treatment rate and risk factors for DR. Logistic regression models were used to estimate odds ratios(OR)and 95% confidence intervals(CI)after adjustment for age, gender and the duration of diabetes.

RESULTS: DR was present in 334(11.68%)of the 2859 community residents aged >60 years old and 1097(25.66%)of the 4275 hospital patients with T2DM, and 48(14.81%)of the residents and 172(15.68%)of the hospital patients required ophthalmic therapy. In univariate and multivariate logistic analyses, factors including the age of the patients(51-60 years old: OR, 1.68; 95%CI, 1.21-1.72; 61-70 years old: OR, 1.55; 95%CI, 1.38-1.76), the duration of diabetes(11-15 years: OR, 2.61; 95%CI, 1.51-4.72; >15 years: OR, 4.15; 95%CI, 2.32-5.77), glycaemic control(medium: OR, 2.51; 95%CI, 1.98-3.92; poor: OR, 4.69; 95%CI, 3.39-6.95), and knowledge of DR(did not understand: OR, 1.45; 95%CI, 1.21-1.95)were significantly associated with the required-treatment rate in DR, while gender, low and advanced age(31-50 years old and >70 years old), duration of disease(<10y), hypertension, and insulin treatment did not.

CONCLUSION: The prevalence rate and the required-treatment rate in DR in Qingdao are relatively high. Being aged 51-70 years old and having a duration of diabetes >10y, poor glycaemic control and a lack of knowledge of DR were found to be potential risk factors that increased the rate of required ophthalmic therapy in patients with DR. In patients with T2DM who were aged 51-70 years old, we found that focusing on using science and education to strengthen the patients' knowledge of DR, establishing specifications for a community DR screening system, and effectively implementing early intervention in the community of DR-affected individuals were particularly important for preventing and controlling the high DR prevalence and the high rate of DR-associated blindness