A cross-sectional survey of the nature and correlates of sleep disturbance in people with psoriasis.
BACKGROUND
Research suggests that sleep disturbance is common in psoriasis. While several sleep investigations have been conducted in psoriasis populations, many have methodological shortcomings, and no study has examined multiple dimensions of sleep-wake functioning. Moreover, research has yet to be performed comprehensively examining the range of physical and psychological factors that may affect sleep in people with psoriasis.


OBJECTIVE
To characterize sleep disturbance using validated measures and to identify physical and psychological predictors of sleep quality in people with psoriasis.


METHODS
An online survey was conducted (186 respondents; mean age 39·2 years) comprising validated measures assessing sleep [Pittsburgh Sleep; Quality Index (PSQI), Berlin Questionnaire, Pre-Sleep Arousal Scale]; chronotype (Morningness-Eveningness Questionnaire); mood (Hospital Anxiety and Depression Scale); itch (5-D Itch Scale); and psoriasis severity (Simplified Psoriasis Index). Group comparisons and regression analyses were used to examine predictors of poor sleep.


RESULTS
The mean PSQI score was 9·2 ± 4·3, with 76·3% scoring above the threshold for poor sleep (≥ 6 on the PSQI) and 32·5% scoring 'positive' for probable obstructive sleep apnoea (OSA). Poor sleep and high likelihood of OSA were associated with more severe psoriasis (P < 0·05; η = 0·07; η2= 0·005). Cognitive arousal (β = 0·26, P = 0·001), itch (β = 0·26, P < 0·001) and depression (β = 0·24, P = 0·001) were the most robust predictors of poor sleep quality, which, together with somatic arousal (β = 0·17, P = 0·022), accounted for 43% of variance in PSQI scores.


CONCLUSIONS
Poor sleep is common in psoriasis and associated with psychological and physical factors. Rates of probable OSA are also high. Given the importance of restorative sleep for health, sleep complaints should receive greater clinical attention in the management of psoriasis.
Division of Musculoskeletal and Dermatological Sciences, University of Manchester, Manchester, U.K.|Manchester Centre for Health Psychology, University of Manchester, Manchester, U.K.|Manchester Academic Health Science Centre, University of Manchester, Manchester, U.K.
A L
http://orcid.org/0000-0003-2217-3052
AL
Henry
Sleep and Circadian Neuroscience Institute, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, U.K.
S D
SD
Kyle
Department of Psychological Sciences, University of Liverpool, Liverpool, U.K.
A
A
Chisholm
Division of Musculoskeletal and Dermatological Sciences, University of Manchester, Manchester, U.K.|Manchester Academic Health Science Centre, University of Manchester, Manchester, U.K.|Salford Royal NHS Foundation Trust, Manchester, U.K.
C E M
CEM
Griffiths
Division of Musculoskeletal and Dermatological Sciences, University of Manchester, Manchester, U.K.|Manchester Centre for Health Psychology, University of Manchester, Manchester, U.K.|Manchester Academic Health Science Centre, University of Manchester, Manchester, U.K.
C
C
Bundy
D000293:Adolescent; D000328:Adult; D000368:Aged; D001143:Arousal / Q000502:physiology; D003071:Cognition / Q000502:physiology; D003430:Cross-Sectional Studies; D003863:Depression / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011537:Pruritus / Q000209:etiology; D011565:Psoriasis / Q000150:complications*; D012893:Sleep Wake Disorders / Q000209:etiology*; D055815:Young Adult