Longer opioid courses and gabapentin for back pain tied to twice the opioid addiction risk in Medicaid study

A first visit for a sore lower back usually ends with a plan: a prescription, a referral, or both. For most people the pain eases with time, whatever they are given. A study of nearly 400,000 Medicaid patients suggests the choice made at that first visit may still echo a year later, in who goes on to be diagnosed with opioid addiction or an overdose.

Researchers at New York University’s Grossman School of Medicine and Columbia University’s Mailman School of Public Health followed opioid-naive adults from the day they began treatment for a new bout of low back pain. Patients whose first treatment included longer or stronger opioid prescriptions, or a gabapentinoid such as gabapentin, went with two to two and a half times the risk of a later diagnosis of opioid use disorder or overdose. A short, low-dose opioid prescription went with a smaller rise. Starting with physical therapy or chiropractic care went with about a third less risk. Lisa Doan, the first author, and Kara Rudolph, the senior author, report this cohort study of Medicaid-insured adults in JAMA Network Open, published on October 19.

What guidelines already say about treating new back pain

Low back pain ranks among the most common reasons adults seek medical care, and the advice on how to start treating it has been stable for years. The American College of Physicians notes that most patients improve over time regardless of treatment. It recommends starting with treatments that are not drugs, such as superficial heat, massage, acupuncture or spinal manipulation. If medicine is wanted, it points to anti-inflammatory drugs such as ibuprofen, or muscle relaxants. The 2022 opioid prescribing guideline from the US Centers for Disease Control and Prevention goes further. For many common kinds of short-term pain, it says, other treatments are at least as effective as opioids.

A randomized trial has since tested opioids for new back pain directly. In an Australian trial known as OPAL, 347 people with acute back or neck pain got guideline care plus either an opioid or an identical placebo for up to six weeks. At six weeks the opioid group’s pain was no better, and on average slightly worse, than the placebo group’s, and more of them reported side effects such as constipation. The trial’s authors concluded that “opioids should not be recommended for acute non-specific low back pain or neck pain.”

Practice in this cohort lagged the advice. Between 2016 and 2019, before the CDC guideline and the OPAL results, about one patient in five filled an opioid prescription as part of their first treatment, most within a week of starting treatment, while fewer than half received any non-drug therapy. Gabapentinoids, gabapentin and pregabalin, are drugs developed for seizures and nerve pain, and they are sometimes prescribed for back pain as an alternative to opioids. A 2017 review of trials in chronic low back pain found that gabapentin compared with placebo showed minimal improvement of pain, alongside more dizziness, fatigue and trouble with thinking and vision.

To the knowledge of the Columbia and New York University team, no prior studies have evaluated how the choice of first treatment for new low back pain relates to later opioid use disorder in Medicaid patients.

How the Medicaid back pain study worked

The researchers used national Medicaid claims from 25 states that expanded Medicaid early under the Affordable Care Act, covering 2016 to 2019. They picked out adults aged 19 to 63 who had a new diagnosis of low back pain after at least six months without one, who had not used opioids, and who began a new pain treatment within a month. They left out people with cancer, pregnancy or another recent pain diagnosis. That left 399,500 patients, with a median age of 39; 59.5% were women.

Each person’s first treatments were whatever they started in the first 30 days. The team sorted these into 14 categories, from anti-inflammatories and muscle relaxants to physical therapy, chiropractic care and massage, and split opioid prescriptions by strength and length. Strength was measured in morphine milligram equivalents, a standard way of comparing doses of different opioids, with 50 a day as the cut-off for a higher dose and seven days as the cut-off for a longer supply.

The outcome was a new diagnosis of opioid use disorder, a pattern of opioid use that causes harm and is hard to control. A nonfatal opioid overdose also counted, as did starting methadone or buprenorphine, the medicines used to treat the disorder. Outcomes were counted only from day 31 to month 13, so that the treatment came clearly before the diagnosis. The analysis accounted for age, sex, race and ethnicity, income and disability benefits, alcohol and drug problems, psychiatric diagnoses and earlier use of hospitals and clinics. It used a statistical method built to handle many such factors at once.

How much the first back pain treatment mattered

The overall risk was not tiny. By 13 months, 2.3% of the patients still being followed (many had left Medicaid by then) had a diagnosis of opioid use disorder or overdose, 5,084 people out of 224,166, and 1.4% had one by seven months. The authors note that this is higher than earlier estimates for commercially insured adults and for Medicaid patients given opioids after surgery.

Against that background, different first treatments lined up with clearly different risks. Opioid prescriptions above 50 morphine milligram equivalents a day were associated with the largest increase in risk, about two and a half times the risk of not receiving them. Two other first treatments went with roughly double the risk: lower-dose opioids taken for more than a week, and gabapentinoids, each associated with a 2.0-fold increased risk. Short courses of low-dose opioids, a week or less, went with a much smaller increase, about 31%.

The non-drug treatments ran the other way. Chiropractic care was associated with the largest drop in risk, about 33%, and physical therapy with about 31%. Every non-drug, non-procedural therapy went with lower risk. Physical therapy was the most common of these, but only 16.3% of patients started with it, and 10.2% with chiropractic care.

The gabapentinoid result is the one most likely to surprise. These drugs are, in the authors’ words, sometimes perceived as safer alternatives to opioids, and most of the patients who got one did not have an overlapping opioid prescription. Yet they sat alongside longer opioid courses in the risk ranking, and in the six-month analysis they ranked above longer courses of low-dose opioids. The ranking held when the researchers changed how the first-treatment window and follow-up were defined.

How the results fit with other back pain studies

Other teams have found the same pattern in different groups of patients. A Brown University study of Medicare beneficiaries with new low back pain compared people who received only physical therapy or spinal manipulation with those who received only opioids or gabapentinoids. The first group had lower odds of overdose-related hospitalization within 90 days. A 2025 study using a large US health records network compared adults who began with spinal manipulation from a chiropractor with matched adults prescribed ibuprofen: over two years, 0.24% versus 1.51% were diagnosed with opioid use disorder.

None of those studies was randomized either, and they share a weakness: people who choose physical therapy or chiropractic care may differ from those who leave with a prescription in ways that records do not capture. The OPAL trial is the randomized evidence, and it addresses whether opioids help back pain, not whether they lead to addiction.

What a Medicaid claims study cannot settle

The biggest gap is how much pain people were in. The authors list the usual weak points of claims research, including “residual confounding, misclassification, underreporting of diagnoses, and unmeasured differences in pain severity and functional status.” Residual confounding means differences between patients that the analysis could not fully account for. A patient who can barely stand is more likely to leave with a strong opioid and may also be on a different path afterwards, so some of the extra risk could reflect the pain rather than the pill.

Claims also blur the outcome. The authors note that the diagnosis codes for opioid misuse pick up most true cases but probably flag some people wrongly, which is why the authors describe the outcome as an opioid use disorder or overdose diagnosis. Over-the-counter painkillers, prescriptions paid for in cash, illicit drug use and exercise advice from a doctor do not show up in the data. Many patients dropped out of follow-up when their Medicaid coverage ended. And the authors caution that the results may not apply beyond the Medicaid-insured adult population, whose risk of opioid use disorder is higher than that of people with private insurance.

What the results mean for people with new back pain

The study does not change what guidelines already recommend; it adds a reason those recommendations matter. The authors conclude that their results “support prioritizing guideline-recommended nonpharmacologic, noninterventional therapies as first-line care for aLBP,” their abbreviation for acute low back pain. Noninterventional means treatments that are neither drugs nor procedures such as injections. They add: “When opioids are prescribed, minimizing dose and duration remain prudent.”

Treatment for back pain is a decision made with a doctor, who can weigh the severity of the pain and a person’s history. Do not stop or change a prescribed medicine without talking to your doctor.

Across nearly 400,000 Medicaid patients, the first treatment for a sore back lined up with later opioid risk. It was about double with longer or stronger opioids or gabapentin and about a third lower with physical therapy or chiropractic care, a pattern this kind of study can show but not prove.