It’s very common for patients to be experiencing disturbed sleep from an injury or surgery. The pain disrupts sleep throughout the night, and it is common for patients to be very groggy the following day. In recent years, research has started to look into the relationship of pain perception and sleep. The pain disrupts the sleep, yes, but does it also decrease pain tolerance during waking hours.
The most restorative stage of sleep (NREM stage 3) decreases with age, while NREM (dream stage) increases, with older adults sleeping less hours per night. Fun fact, they didn’t discover REM sleep until 1953! This means our older adults are not getting as much deep sleep in comparison to our younger population. Does this put them at increased risk of higher pain? Possibly. For a complete list of sleep stages see this link: https://www.tuck.com/stages/. Recent research has shown a definite symbiotic relationship between sleep and pain. The Journal of Pain Research conducted a survey of 882 patient with chronic low back pain, with 42% saying they slept for less than 6 hours per night (Artner, et al. 2013). Another study supports this, saying less than 6 hours of sleep per night decreases pain threshold (Edwards, et al. 2008).
Other studies are starting to look into sleep and how it affects the pain-reducing opioid centers in the brain, “According to the majority of the studies, sleep deprivation produces hyperalgesic changes. Furthermore, sleep deprivation can interfere with analgesic treatments involving opioidergic and serotoninergic mechanisms of action” (Lautenbacher, Kundermann, & Krieg, 2006). One research group studied the positive effects of napping on pain after one night of sleep deprivation. It’s worth noting that while this study had a very small sample side of 11 healthy subjects, the methods were very well regulated and tested. The results were very interesting, showing that even one night of severe sleep deprivation (sleeping only 2 hours) was enough to elicit a negative response (and in healthy people, nonetheless!). However, sleep deprivation followed by two, thirty-minute naps had a very good impact on pain threshold. They tested thermal pain (heat), pain, and mechanical pain [pain from pressure (commonly higher in fibromyalgia patients)]. The negative impact on thermal pain thresholds were completely abolished by napping both in the morning and afternoon with mechanical pain thresholds showing the same trend towards both morning and evening naps; however, certain parts of the body were more susceptible to mechanical pain than others. Due to the lower back sustaining more pressure stimulus throughout the day, the lower back was not nearly as affected compared to the upper trap muscle. The morning nap had a better impact on mechanical pain compared to the afternoon nap for the trap, while the back was more sensitive to thermal pain (Faraut et al., 2015).
So what are some tips to increase quality of sleep? Neuroscientist Matthew Walker recommends spending time away from artificial lights and screens (laptops, TV’s, phones) an hour prior to bedtime. Your sleep/wake cycle is regulated by light, and the body needs darkness to wind down.
He also recommends getting into the same routine before bed and sleeping/waking the same time every day, regardless of it being the weekend. If you cannot fall asleep in bed, don’t stay in bed. Get up, move into a different room and do a quiet activity away from your bed. Return to your bed when you get sleepy. This consistency will essentially help your brain code “bed=sleep,” and help you fall asleep faster. Keeping your room cooler at night will also improve quality of sleep as your body has to drop your internal temperature by 2-3 degrees to initiate the sleep cycle. Taking a hot bath/shower before bed can also initiate this sleepy feeling as you cool off a few degrees. Avoid all alcohol or caffeine a few hours prior to bedtime (caffeine blocks the most restorative phase of sleep). Meditation can also help. Utilizing breathing techniques or listening to quiet music can also aid in calming down the nervous system and relax muscles.
Artner J, Cakir B, Spierkermann JA, Kurz S, Leucht F, et al (2013). “Prevalence of sleep deprivation in patient with chronic neck and back pain: a retrospective evaluation of 1016 patients.” Journal of Pain Research. 6:1-6. Doi: 10.2147/JPR.S36386
Edwards RR, Almeida DM, Klick B, Haythornthwaite JA, Smith MT (2008). “Duration of sleep contributes to next-day pain report in the general population.” Pain 137: 202–207. doi: 10.1016/j.pain.2008.01.025
Faraut, B., Léger, D., Medkour, T., Dubois, A., Bayon, V., Chennaoui, M., & Perrot, S. (2015). “Napping Reverses Increased Pain Sensitivity Due to Sleep Restriction.” PLOS ONE, 10(2), e0117425. doi: 10.1371/journal.pone.0117425 http://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC4344341&blobtype=pdf
LAUTENBACHER, S., KUNDERMANN, B., & KRIEG, J. (2006). “Sleep deprivation and pain perception.” Sleep Medicine Reviews, 10(5), 357-369. doi: 10.1016/j.smrv.2005.08.001 https://www.ncbi.nlm.nih.gov/pubmed/16386930