The risk of obstructive sleep apnea and its association with indices of general and abdominal obesity in a Nigerian family practice clinic: a cross-sectional study

ABSTRACT Introduction: Obstructive sleep apnea (OSA) is associated with considerable morbidity and mortality. This study assessed the prevalence of high risk of OSA and investigated which anthropometric measure best predicts the OSA risk among patients attending a family practice clinic in a tertiary hospital. Methods: We conducted a descriptive cross-sectional study of 362 consecutive patients (64% females; median age of 54 years). OSA risk was assessed by the Berlin Questionnaire and the patients were divided into two groups according to OSA risk: high and low risk. Anthropometric measurements were conducted as stated in the protocol established in the 3rd National Health and Nutrition Examination Survey. Results: Out of 362 participants, 84 [23.2% (95% CI 19.0%, 28.0%)] had high risk of OSA. Subjects with a high risk of OSA had significantly higher body mass index, waist circumference, hip circumference, and waist-to-height ratio (24.9 vs 23.8, p = 0.002; 89.0 vs 84.0, p < 0.001; 95.0 vs 91.0, p < 0.001; 0.56 vs 0.52, p < 0.001, respectively). Body mass index, waist circumference, hip circumference, and waist-to-height ratio performed similarly in predicting high risk of OSA with Area Under the Curve (AUC) of 0.661, 95% CI (0.592,0.730); 0.659, 95% CI (0.596,0.723); 0.668, 95% CI (0.604,0.733); 0.659 95% CI (0.592,0.725) respectively. The AUCs were similar when the analysis was restricted to those who were overweight. Conclusion: High risk of OSA is moderately prevalent in this population, with measures of central and abdominal adiposity equally predicting the risk.