Relationship of snoring and sleepiness as presenting symptoms in a sleep clinic population

Sleepiness has traditionally been considered medically the cardinal symptom of obstructive sleep apnea syndrome. Snoring is perceived as a social or cosmetic complaint. Without independent medical morbidity, snoring identification and treatment is not a major focus in sleep medicine. We speculate that snoring is a major independent symptom. To evaluate how patients rated snoring symptom severity, we compared the relative significance of a sleep clinic population's presenting symptoms of snoring and sleepiness.

We performed a retrospective analysis of 770 consecutive patients who completed sleep intake evaluation forms at the initial clinic visit, including standardized forms for both sleepiness and snoring using previously validated visual analog scales. Data on symptom magnitude (scale of 1 to 10), symptom importance (scale of 1 to 5), a combined symptom product score consisting of magnitude multiplied by importance (MIP; scale of 1 to 50), the Epworth Sleepiness Scale (ESS; n = 599), and the apnea-hypopnea index (AHI; n = 482; mean +/- SD, 35.6 +/- 31.9 events per hour) were collected.

The mean snoring measures (magnitude, importance, and MIP) were greater than those for sleepiness (MIPsnoring of 32.7 +/- 14.8 versus MIPsleepiness of 22.4 +/- 14.2, p < .001). Snoring scored higher than sleepiness in 72% of individuals. To assess whether sleep apnea or sleepiness severity affected symptom scores, we stratified the subgroup with sleep studies into quartiles by AHI and ESS score. Snoring consistently scored higher than sleepiness in most AHI and ESS quartiles (p < .01). Only in the most severe ESS quartile did any sleepiness measure (importance) score higher than the snoring measure (p < .05).

The presenting symptoms of snoring are larger in magnitude, importance, and severity than those of sleepiness in a broad population of patients with sleep disorders and sleep-disordered breathing irrespective of severity of sleep apnea or sleepiness. Symptoms of major significance are clinically relevant to identifying, diagnosing, and treating patients. Failure of medical providers to appreciate the impact of snoring on this population may affect attempts to identify, diagnose, and treat patients with sleep-disordered breathing.