Self reported snoring and daytime sleepiness in men aged 35-65 years

It has been suggested that snoring alone, without conventional sleep apnoea or hypopnoea, may disrupt sleep and produce substantial daytime hypersomnolence. This study addresses this potential relationship.

Eight hundred and fifty men, aged 35-65 years, drawn from one general practice were visited at home and asked a range of questions potentially related to sleepiness, snoring, and sleep apnoea; these included inquiries about alcohol and cigarette consumption, nasal stuffiness, shift work, hypnotic or other drug use, and medical diagnoses. In addition, measurements of height, weight, and overnight arterial oxygen saturation were made. The relation between snoring and sleepiness, with allowance made for potentially confounding variables, including sleep apnoea, was assessed by multiple logistic regression.

Positive answers to all questions about sleepiness were correlated significantly with self reported snoring. After potentially confounding variables and any sleep apnoea had been controlled for, positive answers to four questions about inappropriate drowsiness or sleepiness were independently related to snoring. For example, the odds ratio of admitting to "having almost had two or more car accidents while driving due to sleepiness" was 5.8 (95% confidence intervals: 2.7-12.5) in an "often" snorer.

Although epidemiological associations such as this do not prove a causal relation, the study suggests that snoring (without classical sleep apnoea) may sometimes reduce sleep quality sufficiently to produce substantial daytime drowsiness.