Opioid and Gabapentinoid Starts Carried the Highest Downstream Harm in Acute Low Back Pain
A large Medicaid cohort study found that the way clinicians first treat acute low back pain can shape opioid-related risk over the next year. Among opioid-naive adults younger than 65 years who received pain treatment within 1 month of diagnosis, initial exposure to opioids or gabapentinoids was associated with higher rates of new opioid use disorder or overdose diagnosis, while nonpharmacologic care was associated with lower risk.
The signal was not subtle. Starting higher-dose opioids, defined as more than 50 mg of morphine equivalents, was associated with the largest relative increase in risk. Lower-dose opioids prescribed for more than 7 days and gabapentinoids were also linked to substantial excess risk. By contrast, chiropractic care and physical therapy were associated with the greatest relative reductions in subsequent OUD or overdose diagnosis.
A Medicaid Cohort of Nearly 400,000 Patients Tracked Across 13 Months
The study used Transformed Medicaid Statistical Information System Analytic Files from 25 states that expanded Medicaid under the Affordable Care Act by 2014. The cohort included 399,500 opioid-naive adults with newly diagnosed acute low back pain who initiated treatment between January 1, 2016, and December 31, 2019. Median age was 39 years, with an interquartile range of 30 to 50 years, and 237,846 participants, or 59.5%, were female.
Follow-up extended for 13 months, beginning with a 1-month exposure assessment window and then 12 months of outcome surveillance. During that period, the cumulative incidence of OUD or overdose diagnosis reached 1.4% by 7 months and 2.3% by 13 months. In a population this large, even modest percentage changes translate into a meaningful burden of downstream harm, especially when treatment choices are made at the first visit or in the first few weeks after diagnosis.
Higher-Dose Opioids and Gabapentinoids Were Tied to More Subsequent OUD or Overdose
Initial treatment choice separated the cohort in clinically important ways. Compared with not initiating that therapy, starting higher-dose opioids was associated with a 146.6% increase in risk of OUD or overdose diagnosis, with a 95% confidence interval from 121.5% to 171.7%. Lower-dose opioids prescribed for more than 7 days were associated with a 105.2% increase in risk, and gabapentinoids were associated with a 101.6% increase.
Those estimates matter because they fit a plausible biological and behavioral pathway. Opioid exposure in a pain condition that is usually self-limited can create persistent pharmacologic dependence, widen the window for repeated prescribing, and increase the odds of misuse, escalation, or transition to broader opioid-related harm. Gabapentinoids are often viewed as a nonopioid alternative, yet their association with increased risk in this cohort suggests that substituting one centrally acting medication for another does not necessarily remove the clinical trajectory toward substance-related injury.
The outcome definition was also clinically grounded: OUD or overdose diagnosis included diagnostic codes for opioid abuse, opioid dependence, opioid-involved overdose, or a prescription for medication used to treat OUD. In other words, the study captured more than one narrow label; it identified a range of opioid-related consequences that can bring patients back into care long after the original back-pain visit.
Chiropractic Care and Physical Therapy Were Associated With Lower Risk
Nonpharmacologic, noninterventional therapies moved in the opposite direction. Initiating chiropractic care was associated with a 32.8% reduction in risk of OUD or overdose diagnosis, the largest relative reduction observed, with a 95% confidence interval from 26.8% to 38.9%. Physical therapy was associated with a 31.1% lower risk, with a 95% confidence interval from 22.1% to 40.1%.
These associations align with a mechanism that is easy to explain at the bedside. For many patients with acute low back pain, early movement-based and manual therapies can reduce pain interference, preserve function, and lower reliance on medications that carry dependence risk. When symptoms are managed without defaulting to prolonged pharmacotherapy, the opportunity for opioid exposure shrinks at the point where prevention is most realistic: the first treatment decision.
Guideline-Concordant Care Gains Weight When Harm Is Measured Beyond Pain Relief
The study directly addresses a familiar gap in routine care. Acute low back pain is common, and guideline-discordant management remains widespread. Clinicians often reach for medications first, especially when patients are in distress and want immediate relief. Yet this cohort shows that the downstream consequences extend beyond short-term pain scores or return visits. The initial prescription pattern itself was associated with whether patients later carried an OUD or overdose diagnosis.
For health systems and Medicaid programs, the findings support a stronger front-end emphasis on nonpharmacologic therapy access. Physical therapy and chiropractic care are not always easy to arrange quickly, particularly for patients facing transportation barriers, prior authorization delays, or limited local availability. Even so, the data argue that these therapies may do more than reduce pain; they may reduce the probability that a back-pain episode becomes the first step in a substance-related clinical cascade.
What This Cohort Can and Cannot Prove
This was a retrospective cohort study, so treatment selection was not randomized. Patients receiving opioids, gabapentinoids, or nonpharmacologic care may have differed in pain severity, prior health status, clinician preference, or other unmeasured factors that shape both treatment choice and later risk. The study nonetheless analyzed a very large Medicaid population across 25 states, and the consistency of direction across treatment categories gives the results practical weight.
The data also fit an important clinical pattern: early exposure to higher-risk analgesic strategies was associated with more downstream OUD or overdose, while nonpharmacologic care was associated with less. The implication is straightforward at the point of care. For opioid-naive patients with acute low back pain, the first prescription is not neutral, and the safest path may be the one that avoids creating opioid exposure in the first place.