REGULAR RESEARCH PAPER Poor self-reported sleep quality and health-related quality of life in patients with chronic fatigue syndrome/myalgic encephalomyelitis Jes us Castro-Marrero 1 | Maria C. Zaragoz  a 1,2 | Sergio Gonz  alez-Garcia 1 | Luisa Aliste 1 | Naia S  aez-Franc  as 3 | Odile Romero 4,5 | Alex Ferr  e 4,5 | Tom  as Fern  andez de Sevilla 1 | Jos  e Alegre 1 1 CFS/ME Unit, Internal Medicine Service, Vall d’Hebron University Hospital Research Institute (VHIR), Universitat Aut onoma de Barcelona, Barcelona, Spain 2 Clinical Research Department, Laboratorios Vi~ nas, Barcelona, Spain 3 Psychiatry Unit, Sant Rafael Hospital (FIDMAG), Barcelona, Spain 4 Sleep Unit, Clinical Neurophysiology Department, Vall d’Hebron University Hospital, Universitat Aut onoma de Barcelona, Barcelona, Spain 5 Instituto de Salud Carlos III, CIBER Enfermedades Respiratorias (CIBERES), Madrid, Spain Correspondence Jes us Castro-Marrero, Vall d’Hebron University Hospital Research Institute, CFS/ ME Unit (Lab. 145 – 1st floor), Passeig de Vall d’Hebron 119-129, E-08035 – Barcelona, Spain. Email: jesus.castro@vhir.org Abstract Non-restorative sleep is a hallmark symptom of chronic fatigue syndrome/myalgic encephalomyelitis. However, little is known about self-reported sleep disturbances in these subjects. This study aimed to assess the self-reported sleep quality and its impact on quality of life in a Spanish community-based chronic fatigue syndrome/ myalgic encephalomyelitis cohort. A prospective cross-sectional cohort study was conducted in 1,455 Spanish chronic fatigue syndrome/myalgic encephalomyelitis patients. Sleep quality, fatigue, pain, functional capacity impairment, psychopatho- logical status, anxiety/depression and health-related quality of life were assessed using validated subjective measures. The frequencies of muscular, cognitive, neuro- logical, autonomic and immunological symptom clusters were above 80%. High scores were recorded for pain, fatigue, psychopathological status, anxiety/depres- sion, and low scores for functional capacity and quality of life, all of which corre- lated significantly (all p< 0.01) with quality of sleep as measured by the Pittsburgh Sleep Quality Index. Multivariate regression analysis showed that after adjusting for age and gender, the pain intensity (odds ratio, 1.11; p<0.05), psychopathological status (odds ratio, 1.85; p< 0.001), fibromyalgia (odds ratio, 1.39; p< 0.05), severe autonomic dysfunction (odds ratio, 1.72; p< 0.05), poor functional capacity (odds ratio, 0.98; p< 0.05) and quality of life (odds ratio, 0.96; both p< 0.001) were sig- nificantly associated with poor sleep quality. These findings suggest that this large chronic fatigue syndrome/myalgic encephalomyelitis sample presents poor sleep quality, as assessed by the Pittsburgh Sleep Quality Index, and that this poor sleep quality is associated with many aspects of quality of life. KEYWORDS impaired quality of life, poor sleep quality, sleep disorders, unrefreshing sleep 1 | INTRODUCTION Chronic fatigue syndrome (CFS), also referred to as myalgic encephalomyelitis (ME), is a chronic, multi-systemic and profoundly J. C.-M. and M. C. Z. contributed equally to this study. Received: 22 December 2017 | Accepted: 23 March 2018 DOI: 10.1111/jsr.12703 J Sleep Res. 2018;27:e12703. https://doi.org/10.1111/jsr.12703 wileyonlinelibrary.com/journal/jsr © 2018 European Sleep Research Society | 1 of 9