Correlation of Various Anthropometric and Craniofacial Variables with Severity of Obstructive sleep Apnea in Indian Population

Abstract

Ethnic craniofacial morphology differences significantly affect upper airway caliber and thus apnea–hypopnea index (AHI). As there is very limited data available from India regarding factors influencing severity of obstructive sleep apnea (OSA), we tried to explore whether anthropometric and craniofacial variable predict severity of OSA. To find out correlation of simple clinical examination of craniofacial morphology and anthropometric measurements with severity of OSA in Indian population. We studied consecutive OSA patients between June 2015 and September 2016. Detailed history, physical examination (including anthropometry, clinical craniofacial assessment) and Level I polysomnography was done. Anthropometric and craniofacial parameters were correlated with AHI, nadir oxygen and percent of total time with oxygen saturation level lower than 90% during sleep (T < 90%). Out of 193 patients, 148 (76.6%) were males and 45 (23.3%) were females with ratio of 3.28:1. Mean age, mean body mass index (BMI) and mean AHI of cohort were 50.24 ± 1.65 years, 30.20 ± 0.84 kg/m2, and 53.83 ± 4.8 events per hour, respectively. With respect to AHI, nadir oxygen and T < 90%, statistically significant correlation was found for modified Mallampati class (p value = 0.001, = 0.009, = 0.002, respectively), waist circumference (p value = 0.002, < 0.001, = 0.001, respectively), neck circumference (p value < 0.001, < 0.001, < 0.001, respectively), BMI WHO cut off (p value < 0.001, < 0.001, < 0.001, respectively), and BMI Asian Indian cut off (p value = 0.001, < 0.001, < 0.001, respectively). Anthropometric and craniofacial variables are easy to perform clinical examinations. Higher modified Mallampati class, WC, NC, BMI, large tonsils and micrognathia are associated with more severe OSA.