New Large Study Links Common Back‑Pain Medication to Increased Risk of Dementia and Cognitive Decline
A growing body of research suggests that a widely prescribed medication for chronic back pain — taken by millions of people worldwide — may be associated with an increased risk of dementia and age‑related cognitive impairment. The findings, published in the peer‑reviewed journal Regional Anesthesia & Pain Medicine, show that adults who receive repeated prescriptions for this drug are more likely to be diagnosed with dementia or mild cognitive impairment over the next decade compared with similar individuals who did not take the medication.
The research has raised concern among clinicians, patients and public health experts because the drug in question — called gabapentin — has long been considered a safer alternative to stronger painkillers such as opioids and has been widely prescribed for chronic low‑back pain and a range of other conditions.
Understanding Gabapentin: What It Is and How It’s Used
Gabapentin was first approved in the early 1990s as an antiepileptic medication — a drug used to treat seizures. Since then, doctors have increasingly prescribed it “off‑label” for various types of chronic pain, especially nerve‑related pain and low back pain. Because it is not chemically or functionally an opioid, gabapentin has often been seen as a safer alternative, with a relatively low risk of dependence or misuse compared with opioid painkillers.
In clinical practice, gabapentin is used not only for pain but also for conditions such as shingles‑related nerve pain, restless leg syndrome, anxiety, and even sleep disturbances. Its mechanism of action involves modulating nerve activity in the brain and spinal cord to blunt pain signals, although the exact biochemical mechanisms aren’t fully understood.
Prescription rates for gabapentin have climbed significantly over the last two decades, in part because of efforts to reduce opioid prescribing amid concerns about addiction and overdose. Today, gabapentin is one of the most commonly used medications in its class in the United States and many other high‑income countries.
The New Study: Large‑Scale Analysis of Health Records
The recent study analyzed electronic health records from a large U.S. database known as TriNetX, which includes anonymized data from dozens of healthcare organizations across the country. Using records from 2004 to 2024, researchers identified adults diagnosed with chronic low back pain and compared those who were repeatedly prescribed gabapentin with those who were not prescribed the drug.
To minimize confounding factors — differences between patient groups that could bias results — the study matched individuals based on age, sex, other medical conditions and pain medications. This method, called propensity score matching, attempts to make the two groups as similar as possible apart from the gabapentin prescriptions themselves.
The research team then tracked outcomes over the subsequent decade, focusing on two main endpoints: a diagnosis of dementia, and mild cognitive impairment (MCI) — a condition characterized by measurable declines in memory and thinking skills that are greater than expected for age but not severe enough to disrupt daily function.
Key Findings: Increased Dementia Risk and Cognitive Impairment
The results were statistically significant and consistent across age groups:
Adults with six or more prescriptions for gabapentin had a 29 % higher relative risk of being diagnosed with dementia compared with matched peers who had chronic low‑back pain but were not prescribed the drug.
The same group also showed an 85 % higher risk of developing mild cognitive impairment.
Among patients with 12 or more prescriptions, risks were even higher — about a 40 % elevated risk of dementia and a 65 % higher risk of MCI.
Younger adults — especially those between about 35 and 64 years of age — showed particularly pronounced increases in risk compared with those who did not take gabapentin.
These findings have been reported widely, with multiple news outlets summarizing the results and noting that the association between gabapentin use and cognitive decline appears to increase with the frequency of prescriptions.
What Do These Numbers Mean in Context?
It’s important to understand what a “29 % higher risk” represents. A relative increase in risk does not necessarily translate directly into huge numbers of additional cases — especially for a condition like dementia, whose baseline risk varies widely by age.
For example, in a younger adult population where the baseline risk of dementia is low, even a 29 % increase might correspond to a small absolute increase in cases. Among older populations, where the baseline risk is higher, relative increases could translate to more substantial increases in the number of people developing dementia over a decade.
However, scientists emphasize that the statistical association identified in this study does not prove that gabapentin causes dementia. Observational studies like this can reveal patterns in large datasets, but they cannot definitively establish causation because other unmeasured factors might also play a role.
Possible Biological Explanations — But Not Yet Proven
Researchers and clinicians have proposed several possible explanations for the observed association, though none has been conclusively proven:
Direct neurological effects: Gabapentin affects neural signaling and neurotransmitter balance. Some have speculated that long‑term modulation of brain activity could potentially have downstream cognitive effects, especially among susceptible individuals.
Lifestyle and pain severity: Chronic pain itself — and decreased physical activity or social engagement that may accompany it — has been linked with higher dementia risk in other research. It’s possible that patients requiring repeated prescriptions are also those with more severe, debilitating pain, which confounds the association.
Polypharmacy: Many patients with chronic pain also take multiple other medications, some of which may have anticholinergic effects or other properties linked with cognitive decline. Parsing out the independent contribution of gabapentin versus other drug exposures remains challenging.
None of these possible mechanisms has been definitively established, and researchers have called for further basic and clinical research to clarify the nature of the relationship.
Limitations and Uncertainties in the Research
Although the study was large and methodologically rigorous for an observational analysis, experts caution against overinterpretation of the findings:
Correlation vs. causation: Observational studies can show associations but cannot prove that the drug directly causes dementia. Unmeasured confounding factors — such as lifestyle, genetics, pain severity, or other medications — might contribute to both gabapentin use and dementia risk.
Lack of dosage data: Because the study relied on prescription records, it could not precisely measure actual dosage taken by patients, nor how long individuals used the drug beyond the number of prescriptions filled.
Variable follow‑up: While the study covered as much as ten years post‑prescription, cognitive outcomes can emerge over longer periods. “Silent” changes in brain health may occur before clinical diagnosis.
Generalizability: The data analyzed came from a U.S. database. Prescribing practices, patient characteristics, and diagnostic criteria for dementia might differ in other countries.
Because of these limitations, many clinicians and researchers argue that the results should be interpreted as a signal needing further investigation — not as definitive proof that gabapentin is unsafe.
What Experts Are Saying
The study’s authors noted that while gabapentin has been widely prescribed due to its perceived safety relative to opioids, these new findings suggest clinicians should monitor cognitive outcomes more closely in patients receiving repeated prescriptions.
Other scientists emphasize the need for randomized controlled trials or mechanistic studies that can better isolate the effects of gabapentin from confounding factors such as pain severity, comorbid conditions, or concurrent medication use.
Some neurologists and pain specialists have pointed out that the potential risk of cognitive effects must be weighed against the harms of uncontrolled chronic pain — which itself can have detrimental effects on quality of life and even cognitive function.
Patient Perspectives and Real‑World Concerns
Patients taking gabapentin for chronic pain have expressed a range of reactions to the study’s findings — from concern about cognitive risks to confusion about what the data means for their personal treatment plans.
Some individuals have reported subjective experiences of “brain fog,” changes in memory or attention, or other cognitive changes they attribute to long‑term medication use, though these reports are anecdotal and not evidence of causality.
Healthcare professionals strongly recommend that patients do not stop or modify medication regimens without consulting their doctor, as abrupt discontinuation of gabapentin can lead to withdrawal symptoms, rebound pain, and other adverse effects.
Clinical Implications: What Doctors Might Change
In response to the findings, clinicians might take several practical steps:
Monitor cognition: Doctors may begin more routine screening for memory and cognitive complaints in patients who have been taking gabapentin long‑term.
Shared decision‑making: Physicians might engage in deeper discussions with patients about the potential risks and benefits of gabapentin, especially for long‑term use.
Alternative therapies: Depending on the individual patient’s pain condition and history, alternative treatments — such as physical therapy, exercise programs, behavioral pain management, or other medications with different risk profiles — may be considered.
Individualized risk assessment: For older adults or those with other dementia risk factors (family history, cardiovascular disease, etc.), clinicians may be especially cautious and vigilant.
Some guideline committees might eventually consider these findings when updating recommendations for chronic pain management — but such changes usually require multiple studies and broader consensus.
Looking Ahead: Research and Public Health Questions
The study has opened several avenues for further research:
Controlled trials: Prospective clinical trials comparing cognitive outcomes in patients randomized to gabapentin versus other pain treatments could help clarify causal relationships.
Mechanistic studies: Research into how gabapentin interacts with neural circuits involved in memory and aging may elucidate biological pathways.
Comparative safety: Studies comparing gabapentin with other non‑opioid pain medications could provide clearer guidance for clinical decision‑making.
Population diversity: Research including more racially, ethnically, and geographically diverse populations would enhance generalizability.
Meanwhile, public health agencies may take note of the findings and consider whether updated prescribing guidance or increased education for clinicians and patients is warranted.
Conclusion: What We Know — and What We Don’t
The large medical records study published in Regional Anesthesia & Pain Medicine has identified a statistically significant association between repeated prescriptions for gabapentin and increased risk of dementia and mild cognitive impairment over the following decade.
This association appears more pronounced in younger adults and seems to increase with the number of prescriptions filled — but the research cannot yet prove that gabapentin causes cognitive decline. Whether the drug itself contributes directly to dementia risk, or whether the association reflects underlying pain severity or other factors, remains uncertain.
For patients and doctors alike, the findings underscore the importance of careful, individualized treatment planning, consideration of non‑drug approaches to pain management, and open communication about risks, benefits, and alternatives.
In the meantime, this emerging science invites more research — including controlled clinical trials and mechanistic studies — to better understand how common pain medications may influence long‑term brain health.
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