Non‐alcoholic fatty liver disease (<scp>NAFLD</scp>) is associated with low level of physical activity: a population‐based study

<jats:title>Summary</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>High intensity exercise improves metabolic status and may potentially mobilise hepatic fat.</jats:p></jats:sec><jats:sec><jats:title>Aim</jats:title><jats:p>To assess the level of physical activity (<jats:styled-content style="fixed-case">PA</jats:styled-content>) of subjects with non‐alcoholic fatty liver disease <jats:styled-content style="fixed-case">(NAFLD</jats:styled-content>).</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Data were obtained from <jats:styled-content style="fixed-case">NHANES</jats:styled-content> (2003–2006). Activity counts obtained from accelerometer readings (ActiGraph, Fort Walton Beach, <jats:styled-content style="fixed-case">FL</jats:styled-content>), from 7 consecutive days quantified total<jats:styled-content style="fixed-case"> PA</jats:styled-content> and time spent engaged in different levels of activity. All measures were counts/minutes/day: (sedentary <100; light 100–0027; moderate, 2020–5999 and vigorous, 6000+). <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> was defined as a fatty liver index >60 (<jats:styled-content style="fixed-case">FLI</jats:styled-content>) in the absence of other chronic liver disease. Subjects with <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> were compared to controls using stratum‐specific Chi‐squared and <jats:italic>t</jats:italic>‐tests. Simple linear regression analyses (with Taylor series linearised variance estimation and weighting) were used to determine the association between <jats:styled-content style="fixed-case">PA</jats:styled-content> levels and <jats:styled-content style="fixed-case">NAFLD</jats:styled-content>. <jats:italic>P</jats:italic>‐values <0.05 were considered significant. Statistical analyses were conducted using <jats:sc>sudaan</jats:sc> version 10.1 and <jats:sc>sas</jats:sc> version 9.1.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>We included 3056 participants. <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> patients were older, had higher BMI, larger waist circumference, higher sum of skinfolds, more likely to have insulin resistance (<jats:styled-content style="fixed-case">HOMA</jats:styled-content> > 3.0) and type‐2 diabetes (all <jats:italic>P</jats:italic>‐values <0.01). Average <jats:styled-content style="fixed-case">PA</jats:styled-content> for <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> subjects was about 28.7 counts/minute/day less than controls (<jats:italic>P</jats:italic> < 0.01). Furthermore, <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> subjects spent less time participating in activity at any level (<jats:italic>P</jats:italic> < 0.01). Subjects with <jats:styled-content style="fixed-case">NAFLD</jats:styled-content> and <jats:styled-content style="fixed-case">DM</jats:styled-content> were in the lowest quartile of average <jats:styled-content style="fixed-case">PA</jats:styled-content> as well as moderate‐vigorous <jats:styled-content style="fixed-case">PA</jats:styled-content> (<jats:italic>P</jats:italic> < 0.01).</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>Data from this study show that non‐alcoholic fatty liver disease patients have low level of physical activity and, when they have <jats:styled-content style="fixed-case">diabetes mellitus</jats:styled-content>, they perform at the lowest quartile of <jats:styled-content style="fixed-case">physical activity</jats:styled-content> and moderate‐vigorous physical activity.</jats:p></jats:sec>