Association of combined exposure to multiple metals with comorbid obesity and myopia in the U.S. population

The objective of this study was to examine the relationships between combined metal exposure and the comorbidities of overweight/obesity (OWOB) and myopia. Data from the National Health and Nutrition Examination Survey (2001-2006) were analyzed. The sample comprised 5927 participants aged 12 years and older, with urine measurements of 11 metals obtained through inductively coupled plasma-mass spectrometry. Least absolute shrinkage and selection operator regression models were employed to evaluate the combined effects of the metals. Multivariate logistic regression models and restricted cubic spline functions assessed the connections between metal exposure and comorbidities. The findings indicated that 1290 (21.76%) of the 5927 participants exhibited both OWOB and myopia. High levels of lead (OR = 0.76, 95% CI: 0.62-0.93), platinum (OR = 0.81, 95% CI: 0.68-0.97), and uranium (OR = 0.72, 95% CI: 0.59-0.86) were associated with a reduced risk of these comorbidities (P trend < 0.05). Conversely, elevated exposure to mixed metals was linked to an increased risk of comorbidities (OR = 1.48, 95% CI: 1.23-1.77, P trend < 0.0001). Females had a higher risk of exposure to mixed metals (OR = 4.63, 95% CI: 2.63-8.16) compared to males (OR = 1.45, 95% CI: 0.74-2.82). This study offers preliminary evidence of an association between metal exposure and the comorbidity of OWOB and myopia. Although causality cannot be inferred due to the cross-sectional nature of the study, these results support further longitudinal research.