title: Associations between sleep quality and inflammatory markers in patients with schizophrenia.
abstract: Sleep disorder is a risk factor for several systemic inflammation-related diseases and there are extensive data showing that schizophrenia is associated with chronic low-grade systemic inflammation. This study investigated the associations between sleep quality and inflammatory markers in patients with schizophrenia, which has not been examined before. Sleep quality (total sleep time, sleep efficiency, sleep onset latency, total activity counts, wake after sleep onset, number of awakening, and average length of awakening) was measured using actigraphy in 199 schizophrenia inpatients. The state of inflammation was measured using blood concentration of white blood cells (WBC) and neutrophils, together with neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR). The results showed that total sleep time was negatively associated with NLR and PLR, and sleep efficiency was negatively associated with neutrophil counts and NLR. Sleep onset latency, total activity counts, wake after sleep onset, and number of awakening were positively associated with WBC and neutrophil counts. The average length of awakening was positively associated with NLR and PLR. This is the first report to suggest that improving sleep quality may modulate the state of inflammation in patients with schizophrenia.
authors.affiliation: Institute of Athletics, National Taiwan University of Sport, No 16, Sec 1, Shuan-Shih Road, Taichung 404, Taiwan. Electronic address: shfang@ntupes.edu.tw.
authors.forename: Shih-Hua
authors.initials: SH
authors.lastname: Fang
authors.affiliation: Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192 Tokorozawa, Japan. Electronic address: katsu.suzu@waseda.jp.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Suzuki
authors.affiliation: Lee Kong Chian School of Medicine, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore. Electronic address: fabianlim@ntu.edu.sg.
authors.forename: Chin Leong
authors.initials: CL
authors.lastname: Lim
authors.affiliation: Jianan Psychiatric Center, Ministry of Health and Welfare, 80, Lane 870, Zhongshan Road, Tainan 717, Taiwan. Electronic address: mschung3@gmail.com.
authors.forename: Ming-Shun
authors.initials: MS
authors.lastname: Chung
authors.affiliation: Graduate Institute of Sports and Health, National Changhua University of Education, 1, Jin-De Road, Changhua 500, Taiwan; Department of Epidemiology and Public Health, University College London, London, 1-19 Torrington Place, London WC1E 6BT, UK. Electronic address: powen.ku@gmail.com.
authors.forename: Po-Wen
authors.initials: PW
authors.lastname: Ku
authors.affiliation: Department of Epidemiology and Public Health, University College London, London, 1-19 Torrington Place, London WC1E 6BT, UK; Department of Exercise Health Science, National Taiwan University of Sport, No 16, Sec 1, Shuan-Shih Road, Taichung 404, Taiwan. Electronic address: ljchen@ntupes.edu.tw.
authors.forename: Li-Jung
authors.initials: LJ
authors.lastname: Chen
mesh_terms: D000328:Adult; D001792:Blood Platelets; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007249:Inflammation; D007958:Leukocyte Count; D018655:Lymphocyte Count; D008214:Lymphocytes; D008297:Male; D008875:Middle Aged; D009504:Neutrophils; D010976:Platelet Count; D012307:Risk Factors; D012559:Schizophrenia / Q000097:blood / Q000150:complications / Q000276:immunology* / Q000503:physiopathology; D012890:Sleep; D012893:Sleep Wake Disorders / Q000097:blood / Q000150:complications / Q000276:immunology* / Q000503:physiopathology
keywords: Actigraphy; Insomnia; Neutrophil–lymphocyte ratio; Platelet–lymphocyte ratio; White blood cell