Why carry out this study?

Sleep problems are highly prevalent in patients with chronic pain conditions; the direction of causality remains unclear.

Evidence of the longitudinal relationships of sleep disturbance with pain severity and its distribution is lacking.

We sought to examine the long-term relationships between sleep disturbance and pain intensity and multisite pain, and the persistent impact of sleep disturbance on pain.

What was learned from the study?

We found that sleep disturbance was associated with greater pain severity and more painful sites. Further, there was a reciprocal relationship between persistent sleep disturbance and persistent pain.

The findings of this study highlight that treatment should target both sleep and pain in pain and sleep management in clinical practice, and that treating either problem could help the other.