Aim: To identify the risk factors and their strength of association for persistent opioid use in older people with chronic non-malignant back pain.
Methods: We conducted a systematic review of cohort studies of older people (≥60 years) with chronic back pain (≥3 months), that measured persistent use of opioids (≥90 days). We searched 13 databases for all published literature from inception to 22 January 2025. Two independent reviewers completed data screening and extraction. The review was prospectively registered (PROSPERO ID: CRD42024589930). Risk of bias was assessed using the modified Quality in Prognosis Studies tool. The overall certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE).
Results: Five studies (N=23,328), published between 2003 and 2024, met the inclusion criteria. Due to heterogeneity between these studies, pooling of studies using meta-analysis was not possible. The risk factors for persistent opioid use were depression (Odds Ratio (OR): 7.88, 95%CI: 2.04 to 30.40) and substance abuse disorder (OR 4.72, 95% CI: 1.84 to 12.10) for those taking opioids vs non-steroidal anti-inflammatory drugs. Continued opioid use at 2 years after spine surgery was nine times higher (OR 9.65, 95% CI: 4.65 to 20.00) for opioid versus non-opioid users. Patients who experienced withdrawal symptoms within the first 3 months after spine surgery failed to discontinue opioid treatment at follow-up (P<0.001). However, four studies had high risk of bias. Three studies were categorised as 'moderate-quality' evidence, and two as ‘low-quality’ evidence in the GRADE assessments.
Conclusions: There is a lack of high-quality evidence about risk factors for persistent opioid use in older persons that would be of value to guide the approach to prescribing opioids to older people with chronic non-malignant back pain. Future studies should examine the influence of patient demographics and psychosocial factors on opioid use in older people.