Influence of gender and anthropometric measures on severity of obstructive sleep apnea

Gender differences influence upper airway anatomy and physiology. The purpose of our study was to evaluate the influence of gender as well as anthropometric measures on severity of obstructive sleep apnea (OSA).

A retrospective review of patients referred to our sleep laboratory for evaluation of OSA was done. Patients with a diagnosis of OSA (Respiratory Disturbance Index (RDI) > 5) were included in the study. Anthropometric measurements were available for all the patients included in the study. Measurements of subjects' height, weight, neck size, and waist and hip sizes were used in the study; waist-hip ratio and neck-to-height ratio were calculated.

Three hundred eighty-six females and 661 males were included. Women were older than men and had a higher body mass index (BMI) and waist-to-hip ratio; men had a thicker neck circumference and a higher neck-to-height ratio. The severity of OSA was significantly higher in males (RDI 41.2 ± 27.9 in men vs. 30.0 ± 26.7 in women, p < 0.0001) despite a lower BMI and age in the men. Severity of OSA, as measured by RDI, varied significantly with changes in anthropometric measures such as neck circumference, and waist and hip sizes in both genders. Waist-to-hip ratio was associated with severity of OSA in men but not in women (p = 0.19 and 0.0001 in women and men, respectively). However, no single anthropometric value was found to be strongly predictive of OSA severity.

Despite having a higher mean BMI and age, women have lower RDI compared with men. Waist-to-hip ratio is more predictive of severity of OSA in men than in women. However, the correlation of anthropometric measures with severity of OSA was weak in our subjects.