Objective: To describe the prevalence of retinal vascular signs and their association with cardiovascular risk factors in a Japanese population.
Design: Population-based cross-sectional study.
Participants: Adult persons aged 35 years or older from Funagata, Yamagata Prefecture, Japan (n = 1481).
Methods: The Funagata Study is a Japanese population-based study of persons aged 35 years or older, and included 1961 nondiabetic participants (53.3% of 3676 eligible subjects). A nonmydriatic retinal photograph was taken of 1 eye to assess retinal microvascular signs. Retinal arteriolar wall signs (focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex) and retinopathy were assessed in 1481 participants without diabetes (40.3% of eligible persons) using a standardized protocol. Using a computer-assisted method, retinal vessel diameters were measured in 921 participants with gradable retinal image (25.1% of eligible persons).
Main outcome measures: Prevalence of retinal microvascular signs and their association with cardiovascular risk factors.
Results: Moderate or severe focal arteriolar narrowing, arteriovenous nicking, enhanced arteriolar wall reflex, and retinopathy were found in 8.3%, 15.2%, 18.7%, and 9.0%, respectively, of the study population. Mean (+/-standard error) values for retinal arteriolar diameter were 178.6+/-21.0 mum, and mean values (+/-standard error) for venular diameter were 214.9+/-20.6 mum. Older persons were more likely to have retinal arteriolar wall signs, retinopathy, and narrower retinal vessel diameters. After adjusting for multiple factors, each 10-mmHg increase in mean arterial blood pressure was associated with a 20% to 40% increased likelihood of retinal arteriolar signs and a 2.8-mum reduction in arteriolar diameter. Retinopathy was associated with higher body mass index and both impaired glucose tolerance and impaired fasting glucose.
Conclusions: In nondiabetic Japanese adults, retinal arteriolar wall signs were associated with older age and increased blood pressure, whereas retinopathy was associated with older age, higher body mass index, impaired glucose tolerance, and impaired fasting glucose. These findings are comparable with data from white populations.