Association Between Serum Trace Elements and Obstructive Sleep Apnea in Iranian Adults: Multiple-exposure Models.

Objectives: The association between trace elements and obstructive sleep apnea (OSA) remains an active area of research, and further studies are needed to clarify these relationships. This study examined correlations between serum essential trace element concentrations and polysomnography-confirmed OSA. Methods: This cross-sectional study included patients recruited from the Sleep Disorders Center of Farabi Hospital in western Iran. Participants were classified as patients with OSA (n=54) or controls without OSA (n=45). Results: Iron (Fe) levels were significantly higher in participants with OSA than in controls (p=0.04). Higher Fe levels were associated with greater odds of OSA (p for trend=0.02). Participants in the fourth Fe quartile had higher odds of OSA than those in the lowest quartile, although this association was of borderline statistical significance (odds ratio [OR], 3.00; 95% confidence interval [CI], 0.96 to 10.00; p=0.06). In contrast, participants in the second and third magnesium (Mg) quartiles had lower odds of OSA than those in the first quartile (Q2: OR, 0.31; 95% CI, 0.09 to 0.96; Q3: OR, 0.26; 95% CI, 0.07 to 0.82). In the generalized weighted quantile sum regression model, the association between the metal mixture and OSA was not statistically significant (β=-0.22, p=0.59). Conclusions: Serum concentrations of selected micronutrients may be associated with OSA. The findings suggested a positive association between higher Fe concentrations and OSA, whereas intermediate Mg concentrations were associated with lower odds of OSA.