Dados do Trabalho

Título

EFFECTS OF ORAL MELATONIN ASSOCIATED WITH PULMONARY REHABILITATION ON SLEEP QUALITY AND DAYTIME SLEEPINESS IN COPD

Introdução

Sleep problems are common in COPD. Melatonin (MLT), the main product of the pineal gland, is central to circadian rhythm regulation and its administration reportedly improves sleep in COPD. MLT has also been shown to improve lung oxidative stress in these patients. Pulmonary rehabilitation (PR) can increase exercise tolerance and quality of life and reduce symptoms but it is still unclear if it can improve sleep in patients with COPD. We hypothesized that concomitant administration of MLT could potentialize benefitial effects of PR.

Objetivo

To investigate the effects of oral MLT (3 mg/day) associated with pulmonary rehabilitation for 12 weeks on sleep quality and daytime sleepiness in COPD.

Métodos

This was a double-blind, randomized, placebo-controlled trial. Thirty-nine patients [24 males; mean age (±SD) = 66.6±10,4 years] regularly attending a COPD outpatient clinic at a University Hospital, who were referred for PR, were randomized to receive 3 mg MLT (n = 18) or placebo (n = 21) for the duration of the PR program (12 weeks). At baseline, sleep quality was assessed subjectively by the Pittsburgh Sleep Quality Index (PSQI) and objectively by actigraphy for 7 consecutive days. Daytime sleepiness was measured by the Epworth Sleepiness Scale (ESS). All patients filled a Two Week Sleep Diary. Measures were repeated at the end of the PR program for comparison.

Resultados

On average, patients who received MLT, but not placebo, showed a significant improvement in PSQI global score (respectively, 9.44 ± 4.47 – 4.39 ± 1.88; p < 0.05 vs 7.86 ± 2.97 - 7.62 ± 2.55 p = 0.6). A reduction in the EES score was observed only for the MLT group (respectively, 9.1 ± 6.0 - 6.7 ± 4.5; p = 0.02 vs 10.1 ± 5.0 - 9.5 ± 5.1; p = 0.2). Data obtained from sleep diary showed an increase in total sleep time (329.1±667.0 - 391.9±73.0; p<0.05) and sleep efficiency (80.64 ± 9 – 87.44 ± 6.7; p<0.05) and a reduction in sleep onset latency (-27.40 minutes; p < 0.05) in patients who received MLT, but not placebo. Actigraphy showed a significant increase in sleep effciency (68.5 ± 14.1 – 80.3 ± 12.9; p<0.05) for the MLT group, despite no changes in sleep latency or duration.

Conclusões

Melatonin supplementation 3 mg over a 12-week period can reduce daytime sleepiness and improve subjective sleep quality as well as some aspects of objective sleep quality in patients with COPD undergoing pulmonary rehabilitation.

Palavras-chave

COPD, melatonin, sleep, pulmonary rehabilitation, actigraphy