Initial Choice of Spinal Manipulative Therapy for Treatment of Chronic Low Back Pain Leads to Reduced Long-term Risk of Adverse Drug Events Among Older Medicare Beneficiaries.

Study Design: Retrospective observational study.

Objective: Opioid Analgesic Therapy (OAT) and Spinal Manipulative Therapy (SMT) are evidence-based strategies for treatment of chronic low back pain (cLBP), but the long-term safety of these therapies is uncertain. The objective of this study was to compare OAT versus SMT with regard to risk of adverse drug events (ADEs) among older adults with cLBP.

Summary Of Background Data: We examined Medicare claims data spanning a 5-year period on fee-for-service beneficiaries aged 65 to 84 years, continuously enrolled under Medicare Parts A, B, and D for a 60-month study period, and with an episode of cLBP in 2013. We excluded patients with a diagnosis of cancer or use of hospice care.

Methods: All included patients received long-term management of cLBP with SMT or OAT. We assembled cohorts of patients who received SMT or OAT only, and cohorts of patients who crossed over from OAT to SMT or from SMT to OAT. We used Poisson regression to estimate the adjusted incidence rate ratio for outpatient ADE among patients who initially chose OAT as compared with SMT.

Results: With controlling for patient characteristics, health status, and propensity score, the adjusted rate of ADE was more than 42 times higher for initial choice of OAT versus initial choice of SMT (rate ratio 42.85, 95% CI 34.16-53.76, P < 0.0001).

Conclusion: Among older Medicare beneficiaries who received long-term care for cLBP the adjusted rate of ADE for patients who initially chose OAT was substantially higher than those who initially chose SMT.Level of Evidence: 2.