Association of Physical Activity with Retinal Thickness and Vascular Structure in Elderly Chinese Population

Abstract

Introduction: We aimed to assess the association of physical activity (PA) with retinal thickness and vascular structure in an elderly Chinese population. Methods: This study enrolled 220 retirees aged 50 years and above from Tianjin University of Sport, China. PA data gathered through the International Physical Activity Questionnaires were computed for metabolic equivalent of task-minutes per week. All participants underwent full ophthalmic examination including optical coherence tomography angiography (OCTA). Multiple linear regression analyses were used to evaluate the association of PA with retinal thickness and vascular structure. Results: A high amount of total PA was associated with smaller size of foveal avascular zone (FAZ) (high vs. low: area, β=-0.04; circumference β=-0.14) and greater central vessel (VD) (β=1.04) and perfusion densities (PD) (β=0.02). For domain-specific PA, participants with high and moderate recreational PA levels were found to have greater central VDs and PDs. Non-leisure activities demonstrated negative relationship with FAZ perimeter ratio (moderate vs. low: β=-0.08; high vs. low: β=-0.13) and, counter-intuitively, negative relation with VDs measured at the inner (high vs. low: β=-0.98) and outer retinal layers (high vs. low: β=-0.38). Additionally, higher levels of total PA were related to increased macular fovea thickness and average thickness of retinal nerve fiber layer. Conclusions: High PA level, particularly recreational PA, was associated with smaller FAZ and greater VD and PD in senior adults. Non-leisure time PA might not confer the same health benefits as leisure time PA. Our data supports a possible protective role of recreational PA in the retina against microvascular changes.