Is there an association between serum 25-hydroxyvitamin D concentrations and obstructive sleep apnoea? A cross-sectional analysis of NHANES 2007-2008 data.

OBJECTIVES

The study aimed to investigate the relationship between serum 25-hydroxyvitamin D (25(OH)D) concentrations and obstructive sleep apnoea (OSA) and to assess the confounding effect of body mass index (BMI) on this relationship.

DESIGN

This was a cross-sectional analysis using data from the 2007-08 National Health and Nutrition Examination Survey (NHANES).

SETTING

Data were sourced from NHANES, a continuous survey sponsored by the Centres for Disease Control and Prevention, covering residents from 15 urban areas in the United States of America(USA).

PARTICIPANTS

The study included 4901 participants aged 16 years and older who had completed 25(OH)D data and responses to the OSA questionnaire.

MAIN EXPOSURE MEASURE

Serum 25(OH)D concentrations were measured using liquid chromatography-tandem mass spectrometry.

MAIN OUTCOME MEASURE

The primary outcome was the self-reported diagnosis of OSA from questionnaires.

RESULTS

After adjusting for age, sex and race (model 1), a significant negative association was observed between 25(OH)D and OSA (β=-3.21, 95% CI: -6.17 to -0.26). However, this association was no longer significant after further adjustment for BMI (model 2) (β=1.47, 95% CI: -1.48, 4.42). In the fully adjusted model (model 3), there was no significant association between 25(OH)D and OSA (β=0.92, 95% CI: -1.93, 3.76). Subgroup analyses stratified by sex, age, race or BMI also revealed no significant associations between 25(OH)D and OSA.

CONCLUSIONS

The study found no significant association between 25(OH)D and OSA. The observed correlation between lower levels of 25(OH)D and OSA may be due to confounding factors, such as higher BMI in the OSA group. Therefore, improving obesity management in OSA patients may be necessary to prevent 25(OH)D insufficiency. This underscores the importance of comprehensive management of both OSA and obesity to promote optimal health outcomes.