Relationship between visual acuity and muscle mass in the Korean older population: a cross-sectional study using Korean National Health and Nutrition Examination Survey

Objectives We aimed to assess the effects of visual acuity on muscle mass, which is an important indicator of health in older populations.Design Pooled-sample cross-sectional study.Setting Nationally representative population survey data.Participants The present study analysed men aged 65 years or older who participated in the Korea National Health and Nutrition Examination Survey (KNHANES, 2008–2011).Primary and secondary outcome measures Muscle mass was measured by dual-energy X-ray absorptiometry scan, and low muscle mass was defined as appendicular skeletal mass divided by height squared (kg/m2)