Among individuals with chronic low back pain, sleep disturbance was related significantly with chronic pain intensity and function via both direct and indirect pathways. This according to a study that included 87 individuals (64% female) with chronic low back pain but not using opioids daily who completed questionnaires assessing their sleep disturbance, chronic pain intensity, function, depression, anxiety, positive affect, and catastrophizing. Researchers found:

• Greater sleep disturbance was associated with greater pain intensity, worse function, greater emotional distress, lower positive affect, and higher levels of catastrophizing.
• In cross-sectional mediation analyses, the positive associations between sleep disturbance and chronic pain intensity were conveyed statistically not only via significant indirect effects of elevated emotional distress, lower positive affect, and greater catastrophizing associated with sleep disturbance, but also by significant direct effects of sleep disturbance on chronic pain intensity.
• The associations between sleep disturbance and impaired function were similar.