We investigated the influence of sleeplessness and number of insomnia symptoms on the probability of recovery from chronic low back pain (LBP), and the possible interplay between sleeplessness and co-occurring musculoskeletal pain on this association.
The study comprised data on 3712 women and 2488 men in the Norwegian HUNT study who reported chronic LBP at baseline in 1995–1997. A modified Poisson regression model was used to calculate adjusted risk ratios (RRs) for the probability of recovery from chronic LBP at follow-up in 2006–2008, associated with sleep problems and co-occurring musculoskeletal pain at baseline.
Compared with persons without sleeplessness, persons who often/always experienced sleeplessness had a lower probability of recovery from chronic LBP (RR 0.65, 95% CI 0.57 to 0.74 in women and RR 0.81, 95% CI 0.69 to 0.95 in men). Although there was no clear evidence of statistical interaction between sleeplessness and co-occurring musculoskeletal pain, women and men who often/always experienced sleeplessness and had ≥5 additional chronic pain sites had RRs of recovery of 0.40 (95% CI 0.33 to 0.48) and 0.59 (95% CI 0.45 to 0.78), respectively, compared with persons without sleeplessness and 1–2 chronic pain sites.