Study objectives: While age and body-mass index (BMI) are well-established risk factors for obstructive sleep apnea syndrome (OSAS), this disorder occurs across a wide spectrum of ages and weights. Preconceptions regarding "classic" patients with OSAS may lead to underdiagnosis in at-risk populations, particularly younger nonoverweight individuals. We hypothesized that the severity of OSAS is independent of age and BMI in a younger less-obese population.
Methods: Prospective study of consecutive patients diagnosed with OSAS. Active-duty military, National Guardsmen, and civilians were compared to determine if age and BMI correlated with disease severity.
Results: Two hundred seventy subjects (120 active-duty, 80 National Guardsmen, 70 civilians) were included. Active-duty military members were significantly younger and less overweight than both National Guardsmen and civilians. Of the civilians, 64.3% and, of National Guardsmen, 48.8% were obese, whereas only 19.2% of active-duty had a BMI > or = 30 kg/m2 (p < .001). However, the prevalence of severe disease did not differ between groups. Disease severity showed no correlation with BMI among active-duty subjects (r = 0.09, p = .33). Of the active-duty subjects, 37.5% had severe disease, as compared with 42.5% of National Guard and 45.7% of civilian subjects (p = .18 and .09, respectively). BMI did not differ between active-duty subjects with severe disease and those with mild to moderate OSAS (26.7 kg/m2 versus 26.9 kg/m2, p = .40). There was a low but significant correlation between age and AHI (r = 0.21, p = .02) among all subjects.
Conclusions: OSAS occurs in young nonobese individuals and should be considered in patients reporting excessive daytime sleepiness, regardless of age or BMI.