Sex Differences in Obstructive Sleep Apnea by Bioelectrical Impedance Analysis

Area of Science:

• Sleep Medicine
• Cardiorespiratory Sleep Medicine
• Obesity and Metabolism

Background:

• Obesity is a known risk factor for obstructive sleep apnea (OSA).
• Body Mass Index (BMI) is a limited indicator of body composition, failing to differentiate fat and muscle mass.
• Bioelectrical Impedance Analysis (BIA) offers a potential method to assess body composition in OSA patients.

Purpose of the Study:

• To investigate the utility of BIA in analyzing fat and muscle distribution in male and female OSA patients.
• To determine if BIA parameters correlate with OSA severity as measured by the apnea-hypopnea index (AHI).

Main Methods:

• A cohort of 2,064 OSA patients (AHI ≥5/hour) underwent overnight polysomnography (PSG) and BIA.
• Data collection occurred at Samsung Medical Center, Seoul, Korea, between December 2017 and December 2019.
• Statistical analyses explored correlations between BIA parameters and AHI, stratified by sex.

Main Results:

• Females with OSA exhibited higher fat indicators and lower muscle indicators compared to males.
• The apnea-hypopnea index (AHI) significantly correlated with all BIA parameters in the overall OSA cohort.
• In males, the skeletal muscle mass to visceral fat area (SMM/VFA) ratio showed a strong correlation with AHI after adjusting for age and BMI, unlike in females.

Conclusions:

• Body composition, specifically fat and muscle distribution, differs significantly between male and female OSA patients.
• The SMM/VFA ratio, assessed via BIA, is a key indicator associated with OSA severity in males, but this association is not observed in females after adjusting for covariates.