Physical activity can influence the relationship between ethylene oxide and risk of kidney stones: A cross-sectional study from the NHANES 2013-2016

Ethylene oxide (EO) is known to cause inflammatory damage, and suitable physical activity can reportedly affect the risk of kidney stones. In this study, we aimed to investigate the relationship between EO and kidney stones and whether physical activity can potentially influence the relationship between EO and kidney stones. Overall, 3,336 adult participants were included; of them, 330 (9.9%) had a self-reported history of kidney stones. Data were obtained from the National Health and Nutrition Examination Survey 2013-2016. Physical activity was calculated using metabolic equivalent, weekly frequency, and duration. Logistic regression and restricted cubic spline (RCS) curves were used to explore the association between physical activity, EO, and kidney stones. Dose-response curves from the RCS showed a nonlinear positive association between EO and kidney stones. Multivariate logistic regression analysis revealed an adjusted odds ratio (aOR) of 1.548 (95% confidence interval 1.123-2.135, P = 0.008) for the risk of kidney stones among participants in the highest quartile (Q4) group compared with those in the lowest quartile (Q1) group. Furthermore, compared to the Q1 group, the aOR for risk of kidney stones in the Q4 group was 1.326 in participants without physical activity, a decreased risk (aOR 1.239) in participants with low physical activity, and an increased risk (aOR 1.981) in those with high physical activity. This study suggests that EO is a risk factor for kidney stones and that suitable physical activity may moderate this relationship to some extent; however, excessive physical activity can exacerbate this relationship.