Sleep characteristics of persons with chronic fatigue syndrome and non-fatigued controls: results from a population-based study

BACKGROUND: The etiology and pathophysiology of chronic fatigue syndrome (CFS) remain inchoate. Attempts to elucidate the pathophysiology must consider sleep physiology, as unrefreshing sleep is the most commonly reported of the 8 case-defining symptoms of CFS. Although published studies have consistently reported inefficient sleep and documented a variable occurrence of previously undiagnosed primary sleep disorders, they have not identified characteristic disturbances in sleep architecture or a distinctive pattern of polysomnographic abnormalities associated with CFS. METHODS: This study recruited CFS cases and non-fatigued controls from a population based study of CFS in Wichita, Kansas. Participants spent two nights in the research unit of a local hospital and underwent overnight polysomnographic and daytime multiple sleep latency testing in order to characterize sleep architecture. RESULTS: Approximately 18% of persons with CFS and 7% of asymptomatic controls were diagnosed with severe primary sleep disorders and were excluded from further analysis. These rates were not significantly different. Persons with CFS had a significantly higher mean frequency of obstructive apnea per hour (p = .003); however, the difference was not clinically meaningful. Other characteristics of sleep architecture did not differ between persons with CFS and controls. CONCLUSION: Although disordered breathing during sleep may be associated with CFS, this study generally did not provide evidence that altered sleep architecture is a critical factor in CFS. Future studies should further scrutinize the relationship between subjective sleep quality relative to objective polysomnographic measures

Does nasal decongestion improve obstructive sleep apnea?

Whether nasal congestion promotes obstructive sleep apnea is controversial. Therefore, we performed a randomized placebo-controlled cross-over trial on the effects of topical nasal decongestion in patients with obstructive sleep apnea syndrome (OSA) and nasal congestion. Twelve OSA patients with chronic nasal congestion (mean +/- SD age 49.1 +/- 11.1 years, apnea/hypopnea index 32.6 +/- 24.5/h) were treated with nasal xylometazoline or placebo for 1 week each. At the end of treatment periods, polysomnography including monitoring of nasal conductance by an unobtrusive technique, vigilance by the OSLER test, and symptom scores were assessed. Data from xylometazoline and placebo treatments were compared. Mean nocturnal nasal conductance on xylometazoline was significantly higher than on placebo (8.6 +/- 5.3 versus 6.3 +/- 5.8 mL s(-1)Pa(-1), P < 0.05) but the apnea/hypopnea index was similar (29.3 +/- 32.5/h versus 33.2 +/- 32.8/h, P = NS). However, 30-210 min after application of xylometazoline, at the time of the maximal pharmacologic effect, the apnea/hypopnea index was slightly reduced (27.3 +/- 30.5/h versus 33.2 +/- 33.9/h, P < 0.05). Xylometazoline did not alter sleep quality, sleep resistance time (33.6 +/- 8.8 versus 33.4 +/- 10.1 min, P = NS) and subjective sleepiness (Epworth score 10.5 +/- 3.8 versus 11.8 +/- 4.4, P = NS). The reduced apnea/hypopnea index during maximal nasal decongestion by xylometazoline suggests a pathophysiologic link but the efficacy of nasal decongestion was not sufficient to provide a clinically substantial improvement of OSA