Dietary Selenium Intake and Kidney Stones in Old Adults: an Analysis from NHANES 2011 to 2018

The association between dietary selenium intake and kidney stones remains unclear. The purpose of this study was to explore the correlation between dietary selenium intake and kidney stones in older adults. A total of 6669 adults aged >= 60 years who had participated in the National Health and Nutrition Examination Survey (NHANES) during 2011-2018 were enrolled in the current study. The correlation between dietary selenium intake and kidney stones was assessed by the logistic regression analysis. Smooth curve fitting was used to explore the potential non-linear relationship and subgroup analyses were further adopted. After adjustment for multiple confounding factors, the odds ratio (OR) with 95% confidence interval (CI) of kidney stones for per standard deviation increment in dietary selenium intake was 0.92 (0.85, 1.00) overall. Compared with the lowest quartile, the ORs (95% CIs) with increasing quartiles were 0.88 (0.71, 1.08), 0.82 (0.66, 1.02), and 0.79 (0.64, 0.97). In addition, smooth curve fitting and stratified analyses showed that there was a non-linear and stable correlation between dietary selenium intake and the occurrence of kidney stones respectively. For adults aged over 60, dietary selenium intake was inversely correlated with kidney stones, and this relationship remained after adjusting for other confounding variables. Further researches are needed to explore the potential mechanism between dietary selenium intake and kidney stones.