Visual impairment and objectively measured physical activity and sedentary behaviour in US adolescents and adults: a...

To compare levels of physical activity and sedentary time in a representative sample of US adolescents and adults with and without visual impairment.

Cross-sectional analyses were carried out using data from the National Health and Nutrition Examination Survey.

The study population consisted of 6001 participants (adolescents n=1766, adults n=4235). The present analysis aggregated data from 2003 to 2004 and 2005-2006.

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, non-refractive visual impairment. We estimated the sex-specific linear associations between presenting vision and objectively measured physical activity and sedentary patterns using adjusted generalised linear models in adolescents and adults.

Adolescents with uncorrected refractive error and non-refractive visual impairment did not accumulate higher levels of sedentary time or lower levels of moderate-to-vigorous physical activity (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 non-refractive visual impairment compared with those presenting normal vision (mean difference 329.8 min/week, 95% CI: 12.5 to 647.0). Adults 50 years and older with non-refractive visual impairment appeared to accumulate less lifestyle physical activity, particularly in women (mean difference -82.8 min/week, 95% CI: -147.8 to -17.8). Adult women with non-refractive 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.