Newswise — It is well known that the lack of physical activity is a risk factor for cardiovascular diseases, but what part does it play in retinal vascular caliber? A team of researchers examined the association of physical activity and television viewing time with retinal vascular caliber and explored the differences in white, black, Hispanic and Chinese racial/ethnic groups.

Adults aged 45 to 84 were evaluated in the population-based, cross-sectional Multi-Ethnic Study of Atherosclerosis where retinal vascular calibers were measured. Wider retinal vascular caliber is associated with higher blood pressure, impaired fasting glucose, diabetes, risk of coronary heart disease and other conditions.

Those in the lowest two quartiles of intentional physical activity had a wider retinal venular caliber compared to those in the highest quartile of intentional physical activity except blacks. Similarly, those in the highest quartile of television viewing time had a wider venular caliber compared to those in the lowest quartile. This difference remained significant in whites only.

The results of this study are being presented this week at the 2010 Annual Meeting of the Association for Research in Vision and Ophthalmology. As reported in the abstract, “Results show an association of lack of physical activity and greater TV viewing time with wider retinal venules independent of other cardiovascular risk factors.” The research team also suggested that longitudinal studies be conducted to confirm these associations and further explore ethnic differences.

The Association for Research in Vision and Ophthalmology (ARVO) is the largest eye and vision research organization in the world. Members include more than 12,500 eye and vision researchers from over 80 countries. ARVO encourages and assists research, training, publication and knowledge-sharing in vision and ophthalmology. For more information, visit www.arvo.org. All abstracts accepted for presentation at the ARVO Annual Meeting represent previously unpublished data and conclusions.