To describe the 3 year incidence and cumulative prevalence of retinopathy and its risk factors.
Population-based, prospective cohort study in four U.S. communities
In the Atherosclerosis Risk in Communities Study, 981 participants had retinal photography of one randomly selected eye at the 3rd examination (1993-95) and 3 years later at the 4th examination (1996). Photographs were graded on both occasions for retinopathy signs (e.g., microaneurysm, retinal hemorrhage, cotton wool spots). Incidence was defined as participants without retinopathy at the 3rd examination who developed retinopathy at the 4th examination, and cumulative prevalence was defined to include incident retinopathy as well as participants who had retinopathy at both the 3rd and 4th examinations.
The 3-year incidence anad cumulative prevalence of any retinopathy in the whole cohort was 3.8% and 7.7%, respectively. In multivariable analysis, incident retinopathy was related to higher mean arterial blood pressure (OR 1.5, 95% CI 1.0, 2.3, per standard deviation increase in risk factor levels), fasting serum glucose (OR 1.6, 95% CI, 1.3, 2.1), serum total cholesterol (OR 1.4, 95% CI, 1.0, 2.0), and plasma fibrinogen (OR 1.4, 95% CI, 1.1, 1.9). Among persons without diabetes, the 3 year incidence and cumulative prevalence of non-diabetic retinopathy was 2.9% and 4.3%, respectively. Incident non-diabetic retinopathy was related to higher mean arterial blood pressure (OR 1.4, 95% CI, 0.9, 2.3) and fasting serum glucose (OR 1.5, 95% CI, 1.0, 2.3). Among persons with diabetes, the 3-year incidence and cumulative prevalence of diabetic retinopathy was 10.1% and 27.2%, respectively.
Retinopathy signs occur frequently in middle-aged people, even in those without diabetes. Hypertension and hyperglycemia are risk factors for incident retinopathy.