title: Melatonin improves sleep and reduces nitrite in the exhaled breath condensate in cystic fibrosis--a randomized, double-blind placebo-controlled study.
abstract: Cystic fibrosis (CF) is a chronic progressive disorder characterized by repeated episodes of respiratory infection. Impaired sleep is common in CF leading to reduced quality of life. Melatonin, a secretory product of the pineal gland, has an important function in the synchronization of circadian rhythms, including the sleep-wake cycle, and has been shown to possess significant anti-oxidant properties. To evaluate the effects of exogenous melatonin on sleep and inflammation and oxidative stress markers in CF, a randomized double-blind, placebo-controlled study initially involving 20 patients with CF was conducted. One individual failed to conclude the study. All subjects were clinically stable when studied and without recent infectious exacerbation or hospitalization in the last 30 days. Groups were randomized for placebo (n = 10; mean age 12.1 +/- 6.0) or 3 mg melatonin (n = 9; mean age 16.6 +/- 8.26) for 21 days. Actigraphy was performed for 6 days before the start of medication and in the third week (days 14-20) of treatment. Isoprostane and nitrite levels were determined in exhaled breath condensate (EBC) at baseline (day 0) and after treatment (day 21). Melatonin improved sleep efficiency (P = 0.01) and tended to improve sleep latency (P = 0.08). Melatonin reduced EBC nitrite (P = 0.01) but not isoprostane. In summary, melatonin administration reduces nitrite levels in EBC and improves sleep measures in clinically stable CF patients. The failure of melatonin to reduce isoprostane levels may have been a result of the low dose of melatonin used as a treatment.
authors.affiliation: Department of Medicine, Universidade Federal do Ceará. Rua Prof. Costa Mendes 1608 - 4 Andar, Fortaleza, Ceará, Brazil.
authors.forename: Claudia
authors.initials: C
authors.lastname: de Castro-Silva
authors.forename: Veralice Meireles Sales
authors.initials: VM
authors.lastname: de Bruin
authors.forename: Geanne Matos Andrade
authors.initials: GM
authors.lastname: Cunha
authors.forename: Deuzilane Muniz
authors.initials: DM
authors.lastname: Nunes
authors.forename: Camila Andrade Mendes
authors.initials: CA
authors.lastname: Medeiros
authors.forename: Pedro Felipe Carvalhedo
authors.initials: PF
authors.lastname: de Bruin
mesh_terms: D000293:Adolescent; D000328:Adult; D001944:Breath Tests; D002648:Child; D003550:Cystic Fibrosis / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008550:Melatonin / Q000494:pharmacology* / Q000627:therapeutic use*; D009573:Nitrites / Q000378:metabolism*; D012890:Sleep / Q000187:drug effects*; D055815:Young Adult
chemical_list: D009573:Nitrites; D008550:Melatonin