Objectives: Disturbed sleep and chronic pain are public health concerns. Sleep disturbances seem to influence inflammation and may contribute to the increased pain sensitivity after sleep restriction (SR), such as after night work. The primary objective of this study was to determine the effects of SR on pain sensitivity and on relevant markers of inflammation. A secondary objective was to determine if SR affected pain sensitivity and inflammatory responses differently in men and women.
Methods: A paired crossover design with block randomization was applied. Subjects were instructed to follow their habitual sleep (HS) rhythm for two nights (HS condition) and to delay their bedtime to shorten their sleep with 50% for two nights (SR condition). Thirty-nine healthy volunteers between 19 and 44 years old participated (21 women). Experimental pain sensitivity was tested with heat-, electrical-, and pressure pain thresholds (PPTs); electrical temporal summation threshold; pinprick pain; suprathreshold heat pain tolerance; and rating of suprathreshold heat and cold pain. The following markers of inflammation were measured in plasma from a blood sample taken between 10:00 and 12:00: C-reactive protein, fractalkine, tumor necrosis factor, interleukin -8, and monocyte chemoattractant protein-1.
Results: Most subjects did not comply with the SR instructions. Total sleep [...]