Chronic low back pain (LBP) is a significant issue plaguing our population. Studies have reported 10% of individuals who experience LBP go on to develop chronic or recurrent pain. Out of these individuals, studies indicate that 50% of these individuals, will complain of sleep disturbances.
Sleep is a necessary process for “tissue restoration, growth and energy conservation”. When individuals are deprived of sleep, a hyperalgesic response can occur. This can trigger a deteriorating cycle of pain and sleep in which pain leads to poor sleep, which results in increased pain the next day, which leads to less sleep, and so-on. Studies on healthy individuals even indicate that sleep deprevation results in hyperalgesia, reduced thermal pain thresholds, and cognitive abilities to manage pain. In individuals with conditions related to central sensitization, such as fibromyalgia, fatigue has been reported to be a greater impediment for completing daily tasks than pain. A recent systematic review by Kelly et al. examined the association between sleep and pain.
This review assessed 17 articles which fulfilled the inclusion criteria for assessing the relationship between chronic LBP and sleep. Multiple dimensions of sleep were assessed including sleep disturbance, sleep duration, sleep affecting daytime function, sleep quality, sleep satisfaction and distress, sleep efficiency, ability to fall asleep, activity during sleep, etc.
The authors found that there is consistent evidence that chronic LBP was associated with:
- greater sleep disturbance
- reduced sleep duration and quality
- increased time taken to fall asleep
- poor daytime function
- greater sleep dissatisfaction and distress
These findings demonstrate that a negative association occurs between chronic LBP and sleep. Chronic LBP is a rather complex diagnosis in which many variables can affect it such as: psychological/emotional well-being, coping strategies, ability to work, etc. Despite this review not showing us a casual relationship between the two, we can conclude that at least an associative relationship exists and sleep disturbance should also be addressed in the treatment of chronic LBP because it may be leading to factors impeding the recovery.
Kelly GA, Blake C, et al. The association between chronic low back pain and sleep: A Systematic Review 2011. Clin J Pain; 27: 169-181.