Sex-specific relationship between serum 25-hydroxyvitamin D concentrations and antinuclear antibodies in U.S. adults, NHANES 2001–2004

Abstract

Abstract Background The relationship of serum 25-hydroxyvitamin D concentrations and ANA positivity according to sex stratification is unclear. The propose of this study was to reveal the sex-specific relationship of serum 25-hydroxyvitamin D concentrations and ANA positivity in American people. Methods The study was conducted in 2757 subjects from the National Health and Nutrition Examination Survey (NHANES) 2001–2004. The logistic regression models were used to assess the correlation between the risk of ANA positivity and serum 25-hydroxyvitamin D concentrations. Generalized additive models and smooth fitting curves were used to evaluate the non-linear relationship of the risk of ANA positivity and serum 25-hydroxyvitamin D levels. Results Following multivariable adjustment, we observed a negative correlation between serum 25-hydroxyvitamin D concentrations and the risk of ANA positivity in male participants, particularly in men non-white individuals and those exposed to second-hand smoke. However, there was no significant relationship observed in the female participants. Additionally, the relationship between serum 25-hydroxyvitamin D concentrations and the risk of ANA positivity followed an L-shaped pattern, with an inflection point at 18 ng/mL. When serum 25-hydroxyvitamin D levels fell below this inflection point, decrease of 1 unit in serum 25-hydroxyvitamin D concentrations was linked to an 8% increase in the adjusted OR of ANA positivity (OR 0.92; 95% CI 0.87, 0.97; p 0.0026). Conclusions In American men, nonlinear relationships were observed between serum 25-hydroxyvitamin D concentrations and the risk of ANA positivity.

Keywords

• Antinuclear antibodies (ANA)
• 25-hydroxyvitamin D
• Autoimmunity
• NHANES
• Epidemiology