Impact of chiropractic care on opioid use for noncancer spine pain: systematic review and meta-analysis

Opioids are commonly prescribed for spine-related pain; however, emerging evidence suggests that access to chiropractic care may reduce reliance on opioids. We conducted a systematic review and meta-analysis to assess the impact of chiropractic care on new or continued prescription opioid use among adults with noncancer spine pain. We searched for eligible randomized controlled trials (RCTs) and observational studies in MEDLINE, Embase, AMED, CINAHL, Web of Science, and the Index to Chiropractic Literature up to March 20, 2025. Paired reviewers independently assessed risk-of-bias and extracted data. We performed random- and fixed-effects meta-analyses and used GRADE to assess the certainty of evidence. In total, 2 RCTs (838 participants) and 18 cohort studies (6,035,220 participants) were included in our analyses. We found very low certainty evidence that, compared with standard medical care alone, receipt of chiropractic care may reduce the odds of receiving prescription opioids by 64% (odds ratio [OR] = 0.36; 95% confidence interval [CI], 0.25-0.52; absolute risk reduction [ARR] 15%). However, we found a credible subgroup effect that earlier receipt of chiropractic services (within the first 30 days of presenting with spine-related pain) is associated with a greater decrease in the odds of receiving prescription opioids (OR = 0.33; 95% CI = 0.22-0.51; ARR = 15%) than later (≥30 days after presentation: OR = 0.73; 95% CI = 0.53-0.99; ARR = 8%; test of interaction, P < 0.001), but both with very low certainty evidence. Rigorously designed RCTs are needed to confirm these results.