Association of eight urinary metals and trouble sleeping: A cross-sectional study

While toxic heavy metals have been linked to sleep disorders, the role of less-studied metals remains unclear. We aimed to explore the associations of 8 urinary metals with trouble sleeping and to identify potential gender-specific patterns. This study included 10,012 adults from the National Health and Nutrition Examination Survey 2005-2018. Urinary concentrations of tungsten, arsenic, thallium, cesium, antimony, molybdenum, cobalt, and cadmium were measured. Trouble sleeping was self-reported. We employed weighted logistic regression, restricted cubic spline models, and weighted quantile sum regression to evaluate single and mixed-metal effects. Among participants, 50.2% were male and 25.3% reported trouble sleeping. Higher urinary tungsten levels were associated with increased likelihood of trouble sleeping in males (odds ratios: 1.28-1.30). Arsenic, thallium, and cesium showed inverse associations, with notable gender differences. Weighted quantile sum analysis supported the positive association of tungsten and the inverse associations of arsenic and cesium. No significant associations were found for antimony, molybdenum, cobalt, or cadmium. Urinary tungsten is cross-sectionally associated with trouble sleeping in males, while arsenic, thallium, and cesium show inverse associations, with gender-specific patterns. Further research using validated tools is warranted to validate these associations, elucidate the underlying biological mechanisms, and highlight the significance of assessing combined metal exposures in relation to sleep health.