Opioid Therapy in Chronic Pain: Assessment of Clinical Outcomes and Relationships With Endocrine Biomarkers.

BACKGROUND

Long-term opioid treatment (L-TOT) may have consequences that are mediated by factors affecting functionality and health-related quality of life. This study aimed at investigating associations between L-TOT and clinical outcomes including sustained attention, short-term and working memory, worst pain intensity, sleep quality, mood, and health-related quality of life in patients with chronic non-cancer pain (CNCP). Additionally, the study aimed at exploring whether endocrine biomarkers mediate the relationship between L-TOT and these outcomes.

METHODS

Cross-sectional study with 82 adult CNCP patients divided into two groups (opioid treated (n = 38) and controls not treated with opioids (n = 44)). Linear regression analyses assessed associations between L-TOT, outcome variables, and the mediating effects of endocrine biomarkers. A Bootstrap approach with 95% confidence intervals was applied to analyse the natural indirect effect.

RESULTS

The opioid group had worse sleep quality (p = 0.018), physical functioning (p = 0.0186), social functioning (p = 0.002), and higher pain intensity (p < 0.001) compared with controls. Men in the L-TOT group experienced worse measures for the same variables, and additionally for anxiety (p = 0.028), depression (p = 0.040), role physical (p = 0.038), role emotional (p < 0.001), fatigue (p = 0.019), and emotional well-being (p = 0.001). Only the association between L-TOT and anxiety in men was significantly mediated by total testosterone (β = 1.6, Bias-Corrected Bootstrap 95% CI: 0.1; 4.1, p = 0.045).

CONCLUSIONS

CNCP patients in L-TOT showed significantly poorer outcomes than controls. Only testosterone mediated anxiety in men, indicating a natural indirect effect. Causality and mediating effects of endocrine biomarkers need to be further explored, but the associations are an alert to the potential effects of opioids.

SIGNIFICANCE STATEMENT: This study reveals the broader health impacts of opioid use, particularly the role of hormone-related factors in men, which may be linked to specific adverse effects and consequences. Investigating these hormonal dynamics could lead to improved treatment strategies and outcomes.