OPRM1 Gene Interaction with Sleep in Chronic Pain Patients Treated with Opioids.

Background: The experience of chronic non-cancer pain (CNCP) is one of the most common reasons individuals seek medical attention. Patients with CNCP frequently experience concomitant sleep-related problems.

Objectives: The aim was to evaluate sleep problems in opioid naïve CNCP patients, before and after opioid titration, analyzing the influence of OPRM1 gene variants.