Visual impairment and objectively measured physical activity and sedentary behavior in US adolescents and adults: a cross-sectional study

Objectives: To compare levels of physical activity and sedentary time in a representative sample of US adolescents and adults with and without visual impairment. Design: Cross-sectional analyses were carried out using data from the National Health and Nutrition Examination Survey. Participants: The study population consisted of 6,001 participants (adolescents n=1,766, adults n=4,235). The present analysis aggregated data from 2003-2004 and 2005-2006. Measures: Objective physical activity and sedentary behaviour assessment was conducted over 7 days. Distance visual acuity was measured for each eye in all participants 12 years and older. Participants’ vision was categorised as: normal vision, uncorrected refractive error, nonrefractive visual impairment. We estimated the sex-specific linear associations between presenting vision and objectively measured physical activity and sedentary patterns using adjusted generalized linear models in adolescents and adults. Results and conclusions: Adolescents with uncorrected refractive error and nonrefractive visual impairment did not accumulate higher levels of sedentary time or lower levels of MVPA compared with those with normal vision. We observed no association between vision status and accelerometer measured MVPA in adults aged 20-49 years. We observed more time spent sedentary among females 20-49 years old with nonrefractive visual impairment compared with those presenting normal vision (mean difference 329.8 mins/week, 95% CI: 12.5 to 647.0). Adults 50 years and older with nonrefractive visual impairment appeared to accumulate less lifestyle physical activity, particularly in women (mean difference -82.8 mins/week, 95% CI: -147.8 to -17.8). Adult women with nonrefractive visual impairment have lower levels of lifestyle physical activity and higher levels of sedentary time than those with normal vision. Taken together, these findings highlight the need for interventions to promote physical activity and reduce sedentary time in adult populations with visual impairment, specifically adult women.