Role of hypothyroidism in obstructive sleep apnea: a meta-analysis

Curr Med Res Opin. 2016 Jun;32(6):1059-64. doi: 10.1185/03007995.2016.1157461. Epub 2016 Mar 24.


Objective: This study evaluates the role of hypothyroidism in obstructive sleep apnea (OSA) by comparing the OSA indices in hypothyroid OSA (OSA-HYPOT) with euthyroid OSA (OSA-EUTHY) patients.

Methods: After literature search in several electronic databases and selection of studies by following eligibility criteria, meta-analyses of mean differences/standardized mean differences were performed to compare OSA indices at the time of diagnosis between OSA-HYPOT and OSA-EUTHY patients. Metaregression analyses were carried out to examine the relationship between age, BMI, sample size, and gender vs OSA indices in OSA-HYPOT patients.

Results: Twelve studies and five case reports recruiting 192 OSA-HYPOT and 1423 OSA-EUTHY patients were included in the meta-analysis. Prevalence (mean ± SD) of clinical hypothyroidism in OSA patients was 8.12 ± 7.13% and that of subclinical hypothyroidism 11.07 ± 8.49%. Apnea-Hypopnea Index, time of sleep with oxygen desaturation <90%, and Epworth Sleepiness Scale were significantly higher in the OSA-HYPOT patients at diagnosis, whereas there was no significant difference in arousal index, respiratory disturbance index and sleeping efficiency between OSA-HYPOT and OSA-EUTHY patients. Body mass index was positively associated with Apnea-Hypopnea Index in OSA-HYPOT patients.

Conclusions: Hypothyroidism is found to be associated with severity of OSA. However, obesity can be a confounder in the outcomes observed herein.

Keywords: Apnea; epworth sleepiness scale; hormonal replacement therapy; hypopnea index; hypothyroidism; obstructive sleep apnea.

Publication types

  • Meta-Analysis

MeSH terms

  • Female
  • Humans
  • Hypothyroidism / complications*
  • Male
  • Obesity / complications*
  • Prevalence
  • Sleep
  • Sleep Apnea, Obstructive / epidemiology*
  • Sleep Apnea, Obstructive / etiology