Obesity,obstructive sleep Apnea, and cardiometabolic risk: A comparative analysis of population-Based cohorts in Switzerland, India, and Benin.

PURPOSE: The prevalence and severity of Obstructive Sleep Apnea(OSA) vary by ethnicity, yet data comparing OSA and its anthropometric risk factors across global, population-based cohorts remain limited. We aimed to determine associations between morphological factors and OSA severity, as well as whether OSA-related cardiometabolic risks differ among Swiss, Beninese, and Indian adults. METHODS: We analyzed pooled data from 4,663 adults enrolled in three population-based sleep cohorts: HypnoLaus(Switzerland), BeSAS(Benin), and BLESS(India). Associations between OSA severity (apnea-hypopnea index, AHI) and anthropometric measures [body mass index (BMI), neck circumference, and waist circumference] were examined using multivariable regression models adjusted for age and sex, with effect modification by cohort assessed. Associations between OSA (AHI ≥ 15) and major cardiometabolic comorbidities (hypertension, diabetes, and metabolic syndrome) were also evaluated. RESULTS: For each 1 Kg/m2 increase in BMI, AHI increased by 5.95%, 7.31%, and 8.06% in Beninese, Swiss, and Indians, respectively. OSA was consistently associated with increased odds of hypertension in all populations (OR: 1.30, 1.76, and 1.63 in Swiss, Indian, and Beninese populations, respectively). Moreover, OSA was associated with increased odds of metabolic syndrome [in Swiss (OR:1.64) and Indian (OR: 1.89)]. CONCLUSIONS: Associations between obesity-related anthropometric factors, OSA severity, and cardiometabolic comorbidities differ across populations, with the strongest relationships observed in the Indian and Swiss cohorts. These findings underscore the importance of population-specific risk stratification and highlight the need to consider local anthropometric and epidemiologic contexts in OSA management and prevention strategies.