Improved Sleep And Use Of Caffeine May Provide More Relief From Chronic Pain Than Morphine
A recent study reveals that a long-term lack of sleep could increase sensitivity to pain, and researchers recommend that chronic pain sufferers attempt to get more sleep or consume caffeine to promote wakefulness. Each of these methods was more effective in alleviating chronic pain in mice than common analgesics alone.
Researchers from Boston’s Children’s Hospital and Beth Israel Deaconess Medical Center examined the effects of sleep loss on sleepiness and sensitivity to pain and non-painful stimuli. They administered pain medications such as morphine and ibuprofen, in addition to agents that increase wakefulness such as caffeine and modafinil.
The team analyzed normal sleep cycles using small headsets on the mice, then deprived the animals of sleep by entertaining them with toys and activities instead of tiring them out with exercise. This method of sleep deprivation was meant to mimic the effects of staying up too late and watching TV and other sedentary activities.
Groups of mice were kept awake for up to 12 hours per session, or sis hours for five days in a row. They monitored sleepiness and stress hormones while taking measurements for pain. Sensitivity to pain was measuring using heat, cold, pressure, and capsaicin.
As the mice were exposed to these stimuli, researchers monitored the time it took for the animal to move away from the source of pain. The also measured responses to non-painful stimuli.
Researchers found that five consecutive days of sleep deprivation increased sensitivity to pain and that non-painful stimuli had no effect on the mice’s reactions.
Standard pain relievers such as ibuprofen and morphine did not stop increased pain sensitivity, indicating that sleep-deprived patients might need to increase doses to compensate for sleep loss – an approach that could potentially increase side effects.
However, both modafinil and caffeine appeared to block pain hypersensitivity resulting from sleep loss. In mice who were not sleep-deprived, however, these substances did not appear to relieve pain.
Researchers thus concluded that in addition to pain relievers, patients suffering from chronic pain could benefit from improved sleep (including the use of sleep aids) as well as agents that increase wakefulness which could help break the cycle and provide for relief from chronic pain.
Kiran Maski, MD, Boston’s Children’s Hospital:
“Many patients with chronic pain suffer from poor sleep and daytime fatigue, and some pain medications themselves can contribute to these comorbidities. This study suggests a novel approach to pain management that would be relatively easy to implement in clinical care.”
The study was published this week in Nature Medicine.