Association Between Secondhand Smoke Exposure and Nonalcoholic Fatty Liver Disease in the General U.S. Adult Nonsmoker Population

This study assessed the association between secondhand smoke exposure and the risk of nonalcoholic fatty liver disease (NAFLD) using data from 7412 adult nonsmokers aged 20 years or older who participated in the United States NHANES between 2007 and 2016. Secondhand smoke exposure was measured using serum cotinine levels. Three different noninvasive indexes were used to measure NAFLD. Secondhand smoke exposure was associated with an increased risk of NAFLD, with a linear dose-response relationship. The results of sensitivity analyses and subgroup analyses were consistent.