Pain sensitivity in sleepy pain-free normals.
OBJECTIVE
Past studies have shown that acute experimental reduction of time in bed in otherwise healthy, non-sleepy people leads to hyperalgesia. We hypothesized that otherwise healthy, sleepy people may also exhibit hyperalgesia relative to their non-sleepy counterparts.


METHODS
Between-groups sleep laboratory study.


METHODS
Hospital-based sleep disorders center.


METHODS
Twenty-seven, healthy, normal participants (age 18-35 years) were recruited and categorized into sleepy and non-sleepy groups based on their average sleep latencies on a screening multiple sleep latency test (MSLT).


METHODS
Both groups were then allowed 8 hours time in bed, following which they underwent pain sensitivity testing (10:30 and 14:30) and sleepiness assessments by the MSLT (10:00, 12:00, 14:00, and 16:00). Pain sensitivity assessments were made by measuring finger withdrawal latencies to a radiant heat source delivering 5 different heat intensities.


RESULTS
This study showed that after only one night of 8 hours time in bed, the sleepy participants continued to be sleepy and exhibited a more rapid finger withdrawal response (i.e., increased pain sensitivity) to radiant heat than non-sleepy participants.


CONCLUSIONS
This suggests that sleepy individuals experience hyperalgesia in response to a painful stimulus when compared with non-sleepy individuals.
Chhangani
Bantu Samridhi
BS
Sleep Disorders & Research Center, Henry Ford Health System, Detroit, MI 48202, USA.
Roehrs
Timothy A
TA
Harris
Erica J
EJ
Hyde
Maren
M
Drake
Christopher
C
Hudgel
David W
DW
Roth
Thomas
T
D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000502:physiology*; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000503:physiopathology*; D008297:Male; D017288:Pain Threshold / Q000502:physiology*; D017286:Polysomnography; D011930:Reaction Time / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D055815:Young Adult