A study published in Pain, the official publication of the International Association for the Study of Pain found that people with insomnia and other sleep problems have increased sensitivity to pain.
The study included more than 10,400 adults from a large, ongoing Norwegian health study. Pain sensitivity increased with both the frequency and severity of insomnia. Compared with individuals who reported no insomnia, rates of reduced pain tolerance were 52% higher for subjects reporting insomnia more than once a week versus 24% for those with insomnia once monthly.
There was also a strong joint (synergistic) effect of insomnia and chronic pain on pain tolerance. Patients reporting problems with both insomnia and chronic pain were more than twice as likely to have reduced tolerance to pain.
“While there is clearly a strong relationship between pain and sleep, such that insomnia increases both the likelihood and severity of clinical pain,” Dr. Sivertsen and coauthors write, “it is not clear exactly why this is the case.”
This new study is the first to link insomnia and impaired sleep to reduced pain tolerance in a large, general population sample. The results suggest that psychological factors may contribute to the relationship between sleep problems and pain, but they do not fully explain it.
The study shows the need for efforts to improve sleep among patients with chronic pain and vice versa. Dr. Sivertsen and colleagues believe studies are needed for evaluating earlier interventions targeting patients who are simultaneously affected by both problems.
April 30, 2015