Randomized Placebo-controlled Crossover Trial of Continuous Positive Airway Pressure for Mild Sleep Apnea/Hypopnea Syndrome

Abstract

The minimal disease severity at which patients with the sleep apnea/hypopnea syndrome (SAHS) gain benefit from treatment is not well characterized, although a pilot study of continuous positive airway pressure (CPAP) therapy showed daytime improvements in patients with 5 to 15 apneas + hypopneas per hour slept (AHI). We have thus performed a second, larger, randomized, placebo- controlled study in a prospective series of 34 patients (13 female) with mild SAHS (AHI 5 to 15) and daytime sleepiness. Patients spent 4 wk on CPAP treatment and 4 wk on an oral placebo, with randomization of treatment order, and daytime assessments on the last day of each treatment. Effective CPAP use averaged 2.8 +/- 2.1 h (mean +/- SD) per night. Compared with placebo, CPAP improved symptom score (p< 0.01), subjective (Epworth; p < 0.01) but not objective (maintenance of wakefulness test; p > 0.2) sleepiness, performances on 2 of 7 cognitive tasks (p < 0.02), depression score (p < 0.01), and five subscales of the SF-36 health/functional status questionnaire (p </= 0.03). Fourteen of 34 patients preferred CPAP. In 14 patients with AHI in the range 5 to 10, symptoms, cognitive function, psychological well-being and quality of life were improved. These results confirm benefits for daytime function after CPAP treatment for mild SAHS, but highlight unacceptability of CPAP in many such patients.

Long-term treatment with continuous positive airway pressure improves quality of life in obstructive sleep apnoea syndrome

“…In this study patients were followed for 4 weeks. The results remarkably resembled those in the studies by ENGLEMAN et al [12,13,19], showing that the measures of subjective well-being improved about two-fold compared with placebo. Therefore, from the short-term studies available it can be deduced that placebo or subtherapeutic CPAP have measurable positive effects on subjective well-being, but that there is a clear quantitative difference between CPAP and placebo effects.…”

“…In a smaller group of patients, a similar benefit of CPAP over placebo was reported by the same group [13]. In a further study, this group showed that CPAP therapy also significantly improved well-being in patients with mild sleep apnoea/hypopnoea syndrome as assessed by the Epworth sleepiness scale, a symptom score, performances on two of seven cognitive tasks, depression score, and five subscales of the Short Form-36 health/functional status questionnaire [19].…”

“…Previous research on quality of life measures demonstrated that short-term treatment with CPAP for 4 or 5 weeks, respectively, can improve cognitive performance [12], symptoms of OSAS and daytime function [13,19], and quality of life [14,15,18]. A recently published study demonstrated that the relief of sleepiness and other OSAS-related clinical symptoms and improvement in perceived health status was much greater in patients receiving conservative and CPAP treatment compared with those only receiving conservative treatment, even after 3 months of treatment [17].…”

Continuous positive airway pressure treatment for sleep apnea in older adults

“…This study not only suggests that older individuals with OSA benefit from CPAP treatment, but those with the additional burden of Alzheimer's disease can utilize this therapy achieving gains in alertness. (19,20,22,44) failed to show improvement in objective sleepiness with CPAP treatment, compared to those with more severe disease. (21,23,30,32) CPAP appears to be beneficial in improving self-reported daytime sleepiness in older adults and even in those with dementia, but evidence does not show that it is superior to conservative therapy or placebo for increasing objectively measured daytime sleepiness.…”

Therapy with nCPAP: incomplete elimination of Sleep Related Breathing Disorder

“…"Cut-off points" describing certain hours of nightly CPAP use have been described by other investigators. Some of these "cut-off points" have been set at arbitrary levels [2], based on median group values [3], or based on outcome data related to sleepiness and performance [4]. It has also been suggested that compliance is better defined by CPAP use in relation to total subjective sleep-time.…”