Allergies Alone Not Associated With Increased Risk Of Nighttime Breathing Problems

Nasal obstruction is one of the most troublesome symptoms of nasal and sinus diseases, including allergic rhinitis, according to background information in the article. "People with nasal obstruction often experience other symptoms, including headache, thirst, lack of concentration, daytime cognitive deficits, daytime sleepiness and disturbed sleep, which impair their daily and social activities," the authors write. "There has been growing awareness that the morbidity [illness] of allergic rhinitis in the general population is increasing and is leading to a decline in school and work performance, resulting not only in a medical economic loss but also in a large social economic loss."

To investigate the relationships among nasal obstruction, snoring and excessive daytime sleepiness in people with and without allergies, Nobuaki Hiraki, M.D., and colleagues at the University of Occupational and Environmental Health, Kitakyushu, Japan, analyzed responses to a survey of Japanese workers. Of the 1,878 workers asked to complete questionnaires, 1,615 responded (86 percent) and 1,459 provided sufficient information for the analysis.

Participants were divided into four groups: those with allergies and nasal obstruction, those with nasal obstruction but no allergies, those with allergies but no nasal obstruction and those with neither nasal obstruction or allergies, who served as controls. Those in the nasal-obstruction groups (with or without allergies) had higher odds of snoring and daytime sleepiness than the control group, but there was no difference between the allergies-only and control groups.

"The present results strongly suggest that nasal obstruction causes sleep-disordered breathing and, thus, daytime sleepiness in individuals without allergic rhinitis as well as in those with allergic rhinitis," the authors write. This is thought to occur through several mechanisms, including changes in pressure that cause portions of the throat to collapse, functional difficulties induced by the shift from nasal breathing to mouth breathing and changes in signals sent from the respiratory system to the brain.

"We speculate that, although nasal obstruction itself is not a life-threatening condition, prompt and appropriate rhinologic treatment would improve sleep quality and, thus, daily and social activities in patients with sinonasal diseases," the authors conclude. "This remains to be further investigated in future studies."