High First Opioid Doses for Back Pain Tied to 147% Higher Risk

Medicaid patients who started treatment for a new episode of low back pain with opioids above 50 morphine milligram equivalents a day were 146.6 percent more likely to be diagnosed with opioid use disorder or survive an overdose in the following year than patients who did not receive that dose, according to a study published Oct. 19 in JAMA Network Open.

The retrospective cohort followed 399,500 opioid-naive adults under 65 across 25 states that expanded Medicaid, using claims from January 2016 through December 2019 with 13 months of follow-up. Median age was 39 and 59.5 percent were women. Overall, 1.4 percent had a new opioid use disorder or overdose diagnosis by seven months and 2.3 percent by 13 months.

Those absolute numbers matter as much as the relative ones. A 146.6 percent increase applies to a small baseline risk, so most patients given a stronger first prescription did not develop a disorder. What the study describes is a shift in odds attached to a routine clinical decision — one made for millions of people every year.

What the study measured

The outcome was not a survey response or a single lab result but a claims record: a diagnosis code for opioid abuse or dependence, a code for an opioid-involved overdose, or a prescription for a medication used to treat opioid use disorder. That definition captures both the diagnosis and the treatment that follows it, which is why the researchers describe it as incident opioid use disorder or overdose rather than as problematic use.

Exposure was whatever treatment a patient received in the first month after a new acute low back pain diagnosis. The researchers used a nonparametric, doubly robust estimator to adjust for measured confounding, and stratified patients by the specific first-line path they took — chiropractic, physical therapy, non-opioid medication, low-dose opioids, higher-dose opioids, gabapentinoids.

The participants came from the Transformed Medicaid Statistical Information System analytic files, and the analysis ran from March 2025 to July 2026. By construction the cohort excludes anyone with recent opioid use, so the findings describe people starting fresh, not people already in long-term opioid therapy.

The dose threshold, and the risk below it

The steepest association sat above 50 morphine milligram equivalents per day, the level at which federal prescribing guidance has long advised clinicians to weigh additional precautions.

But the study did not find a safe low-dose floor. Opioids at or below 50 morphine milligram equivalents prescribed for more than seven days were associated with a 105.2 percent higher risk, roughly two-thirds of the increase seen at higher doses. That finding complicates the common clinical assumption that a short course at a modest dose carries little downstream risk — duration mattered on its own.

Two other numbers frame the results. Nonpharmacologic care was associated with lower risk: chiropractic 32.8 percent lower, physical therapy 31.1 percent lower. And the study's own framing notes that guideline-discordant care for acute low back pain is common, a fact established well before these data were assembled. The American College of Physicians has recommended nonpharmacologic treatment as first-line for years.

Gabapentinoids come out nearly as bad

The finding most likely to travel beyond pain medicine is about a drug class usually marketed as the safer alternative. Gabapentinoids — gabapentin and pregabalin — were associated with a 101.6 percent higher risk of opioid use disorder or overdose diagnosis, statistically close to the low-dose opioid result and well above what the researchers found for other medications.

That is an uncomfortable result for prescribers who moved patients off opioids onto gabapentin and considered the substitution harm reduction. Gabapentin was the fifth most prescribed drug in the United States in 2024, reaching 15.5 million patients, with prescriptions nearly tripling since 2010, according to Pain News Network's review of the study and prescribing data. Much of that growth is off-label use for pain, a practice the evidence base does not strongly support.

The mechanism is plausible rather than mysterious. Gabapentinoids and opioids taken together increase sedation and respiratory depression, and co-prescribing is common. The risk pathway in the claims data may run through co-use rather than through gabapentin alone — a distinction the study design cannot fully resolve.

The authors' conclusion is narrower than the headlines built on their numbers: "These results support guideline recommendations favoring nonpharmacologic treatments as first-line therapy for low back pain."

What a claims database cannot see

This was an observational study, so every figure describes an association, not a proven cause. Patients who received higher doses may have had more severe pain, worse function or other unmeasured differences that independently raised their risk, and claims data capture none of that.

Diagnosis codes are also an imperfect proxy. A clinician who documents opioid use disorder may be more attentive, or work in a system with more billing scrutiny, than one who does not. The cohort ends in 2019, before fentanyl dominated the illicit supply and before telehealth prescribing rules changed, so the overdose risk faced by patients in the study differs from the risk a patient faces today.

The study also says nothing about what happens to someone already on long-term opioids, or about medication treatment for people who develop a disorder. It measures the front end of the prescription cascade, not the exits.

What changes for a patient with new back pain

The practical translation is not "never take an opioid." It is that the first prescription is a decision with measurable downstream weight, that dose and duration both move the risk, and that the alternatives with the lowest associated risk are the ones guidelines already recommend and that many patients never get offered.

For anyone who has been on gabapentin for back pain and believes it carries no addiction risk, the study is a reason to ask a prescriber about the evidence rather than assume the substitution solved the problem. For clinicians, the finding that more than half of Medicaid patients in this population did not start with nonpharmacologic care describes a gap in what is available, not only in what is chosen — chiropractic and physical therapy appointments are covered unevenly and are scarce in many of the counties where Medicaid enrollment is highest.

The earlier national trend has been the opposite of these findings' implication: prescriptions for opioids fell while gabapentinoid prescribing climbed, a shift documented in separate claims research this spring. This study suggests the substitution may have moved risk around rather than removing it, which is a harder claim to make in a legislative hearing than in a cohort study — and easier to ignore.