Abstract
Purpose: :
To estimate the long-term incidence of cataract surgery and the associated risk factors in a 25-year follow-up of a population-based cohort of Danish type 1 diabetic patients.
Methods: :
Based on insulin-prescriptions, a population-based cohort of 727 type 1 diabetic patients was identified in 1973. In 1981-82 diabetic retinopathy was graded and other markers of diabetes were measured in 573 patients who participated in a clinical baseline examination. Patients were followed until November 2006. Data on cataract surgery during follow-up were provided by the Danish National Patient Registry and evaluated among all patients regardless of survival status.
Results: :
Of the 573 patients examined at baseline in 1981-82, 11 (1.9%) had already had cataract surgery performed. Among the remaining patients, the crude cumulative 25-year incidence of cataract surgery was 20.8% (117 of 562). The mean age and duration of diabetes at the time of operation for patients who were operated during follow-up were 58.6 and 41.3 years, respectively. In a multivariate analysis, cataract surgery was predicted by age (HR 1.89 per 10 years, 95% CI 1.46-2.46) and maculopathy (HR 1.89, 95% CI 1.05-3.40), but not further associated with duration of diabetes, proliferative retinopathy, glycemic regulation, proteinuria, smoking, BMI, systolic or diastolic blood pressure.
Conclusions: :
A high 25-year incidence of cataract surgery was found in a population-based cohort of type 1 diabetic patients. Cataract surgery was associated with age and maculopathy, but surprisingly glycemic regulation and proliferative retinopathy was not statistically associated with cataract surgery.
Keywords: diabetes • cataract • clinical (human) or epidemiologic studies: risk factor assessment