Epidemiological study of diabetic retinopathy in a primary care setting in Hong Kong.

OBJECTIVES: To estimate the prevalence and risk factors of diabetic retinopathy in type 2 diabetic patients, and to investigate the difference in retinopathy progression in patients with normal fundi or established retinopathy at baseline and the risk factors implicated in the progression. DESIGN: Retrospective community-based study. SETTING: Ten primary care clinics in Hong Kong. PATIENTS: Type 2 diabetic patients; subsidiary analysis included subjects with more than one screening event. MAIN OUTCOME MEASURES: Patient demographics, baseline prevalence, and risk factors of diabetic retinopathy; progression of retinopathy in patients with normal fundi and established retinopathy at baseline, and the associated risk factors. RESULTS: A total of 6165 patients were recruited from January 1998 to May 2004. Primary analysis included 4423 patients with good-quality retinal photographs. The mean age of the patients was 60.36 years (standard deviation, 10.80 years; range, 28-94 years), the mean duration of diabetes was 4.71 years (standard deviation, 4.67 years; range, 0.1-40.6 years), and the mean level of glycated haemoglobin was 7.47% (standard deviation, 1.44%). The prevalence of retinopathy at baseline was 28.4%. Subsidiary analysis showed progression to sight-threatening retinopathy was more common in the group with baseline retinopathy than that without (7.9% vs 0.7%), and occurred at a faster rate (mean, 1.5 [range, 0.5-3.0] vs 2.0 [1.0-4.2] years). Logistic regression revealed that the level of glycated haemoglobin was positively associated with both the onset (P<0.001) and progression of retinopathy (P=0.03). CONCLUSION: Optimal glycaemic control is important for reducing sight-threatening retinopathy. Close observation is required for patients with established retinopathy as progression occurs more rapidly.

The prevalence of microalbuminuria among patients with type II diabetes mellitus in a primary care setting: cross-sectional study.

OBJECTIVES: To determine the prevalence of microalbuminuria among patients with type II diabetes mellitus in a primary care setting, and to study the association between various risk factors and the presence of microalbuminuria. DESIGN: Cross-sectional community-based study. SETTING: Four primary care clinics, Hong Kong. PATIENTS: All patients with type II diabetes mellitus who regularly attended the clinics between May 2002 and March 2003. MAIN OUTCOME MEASURES: Patients' demographic data, the proportion with microalbuminuria (measured using a spot urine test), and the association between this condition and risk factors for diabetic nephropathy (via correlation and multivariable logistic regression analysis). RESULTS: The mean age of the 1161 patients in the sample population was 58.0 years. The mean duration of diabetes mellitus was 5.7 years, and the mean level of glycated haemoglobin was 7.4%. A total of 13.4% of the patients had microalbuminuria. Having the condition was significantly associated with advanced age, female sex, poor glycaemic control, and coexisting hypertension in both correlation and regression analyses. No significant association with ever smoking was found. CONCLUSION: Early screening for incipient diabetic nephropathy and aggressive management of modifiable risk factors in a primary care setting may be important in optimising the renal outcome of patients with type II diabetes mellitus.