Study objectives: Disturbances of sleep are hypothesized to contribute to pain. However, experimental data are limited to healthy pain-free individuals. This study evaluated the effect of sleep loss during part of the night on daytime mood symptoms and pain perceptions in patients with rheumatoid arthritis in comparison with control subjects.
Design: A between-groups laboratory study with assessment of mood symptoms and pain perception before and after partial night sleep deprivation (PSD; awake 23:00 hr to 03:00 hr).
Setting: General clinical research center.
Participants: Patients with rheumatoid arthritis (n = 27) and volunteer comparison control subjects (n = 27).
Measurements: Subjective reports of sleep, mood symptoms and pain, polysomnographic assessment of sleep continuity, and subjective and objective assessment of rheumatoid arthritis-specific joint pain.
Results: PSD induced differential increases in self-reported fatigue (P < 0.09), depression (P < 0.04), anxiety (P < 0.04), and pain (P < 0.01) in patients with rheumatoid arthritis compared with responses in control subjects, in whom differential increases of self-reported pain were independent of changes in mood symptoms, subjective sleep quality, and objective measures of sleep fragmentation. In the patients with rheumatoid arthritis, PSD also induced increases in disease-specific activity as indexed by self-reported pain severity (P < 0.01) and number of painful joints (P < 0.02) as well as clinician-rated joint counts (P < 0.03).
Conclusion: This study provides the first evidence of an exaggerated increase in symptoms of mood and pain in patients with rheumatoid arthritis after sleep loss, along with an activation of rheumatoid arthritis-related joint pain. Given the reciprocal relationship between sleep disturbances and pain, clinical management of pain in patients with rheumatoid arthritis should include an increased focus on the prevention and treatment of sleep disturbance in this clinical population.
Keywords: Sleep; anxiety; depression; fatigue; joint pain; pain; rheumatoid arthritis; sleep deprivation.