Shared genetic basis for obstructive sleep apnea and adiposity measures.

Area of Science:

• Genetics
• Sleep Medicine
• Obesity Research

Background:

• Obesity and obstructive sleep apnea (OSA) share genetic underpinnings and frequently co-occur.
• Quantifying the genetic overlap between these conditions is crucial for understanding their shared etiology.

Purpose of the Study:

• To quantify the genetic overlap between obstructive sleep apnea and anthropometric measures of obesity.
• To determine the extent to which genetic factors for obesity contribute to the genetic variance in sleep apnea.

Main Methods:

• Utilized data from the Cleveland Family Study, including 1802 individuals from 310 families.
• Assessed sleep apnea severity via home and laboratory sleep studies (apnea-hypopnea index - AHI).
• Measured anthropometric variables (BMI, waist, hip, neck circumferences) and adipokines (leptin, adiponectin, resistin); employed variance component models for heritability and genetic correlation analyses.

Main Results:

• Heritability of AHI was estimated at 0.37 (home) and 0.33 (lab).
• Genetic correlations between AHI and anthropometric adiposity measures ranged from 0.57 to 0.61, indicating obesity explains ~40% of the genetic variance in sleep apnea.
• Genetic correlations with adipokines were lower (0.11-0.46); adjusting for BMI eliminated significant genetic correlations with other adiposity measures.

Conclusions:

• Significant genetic overlap exists between sleep apnea and obesity indices, accounting for over one-third of the genetic variance in apnea severity.
• Genetic polymorphisms influence sleep apnea susceptibility through both obesity-dependent and independent pathways.
• These findings highlight shared genetic factors and suggest distinct genetic contributions to sleep apnea risk.