Long-term use of common heartburn pills is tied to kidney and dementia risk

Proton pump inhibitors, the class of heartburn drugs that includes omeprazole, esomeprazole and lansoprazole, are among the most widely used medicines in the world, taken by millions of people for acid reflux and ulcers. They are highly effective at shutting down stomach acid, and many patients stay on them for years, often without a scheduled review of whether the treatment is still needed. Over the past decade a series of large observational studies has linked long-term use to a higher risk of chronic kidney disease and to a smaller, more debated signal for dementia. None of that research proves the pills cause those conditions, but the pattern has been consistent enough to prompt calls for more cautious, time-limited prescribing.

How proton pump inhibitors shut down stomach acid

The drugs work by blocking the enzyme known as the proton pump in the cells lining the stomach, the final step that secretes acid into the digestive tract. That mechanism makes them more powerful and longer-lasting than older antacids or H2 blockers, and it is why they are the standard treatment for gastroesophageal reflux disease, erosive esophagitis and the prevention of ulcers in people taking anti-inflammatory painkillers. The same potency is the reason the drugs draw scrutiny for long-term use. Suppressing acid for years can alter the absorption of nutrients such as magnesium, calcium and vitamin B12 and can change the population of bacteria in the gut, biological effects that give researchers plausible starting points when they look for downstream harm.

The kidney signal from the ARIC cohort

The clearest of the associations involves the kidneys. In a widely cited analysis of the Atherosclerosis Risk in Communities study, researchers reported in JAMA Internal Medicine that participants using proton pump inhibitors developed chronic kidney disease at a rate of about 14.2 cases per 1,000 person-years, compared with 10.7 among nonusers. After adjusting for demographic and clinical differences, users carried a roughly 50 percent higher risk of chronic kidney disease, with the estimate settling near a 30 percent increase in models that accounted for changing use over time. The study drew on more than 10,000 participants followed for well over a decade, which lends the finding weight, though the design still cannot rule out that sicker patients were simply more likely to be prescribed the drugs.

A weaker and more contested link to dementia

The dementia question is murkier. Drawing on the same ARIC population, a later analysis published in Neurology found that current use of proton pump inhibitors was not associated with a statistically significant rise in dementia overall, but that people who had taken the drugs for more than about 4.4 cumulative years showed an elevated risk, with a hazard ratio near 1.3. Other cohort and case-control studies have swung in both directions, some reporting modest associations with Alzheimer’s and vascular dementia and others finding none once confounding factors were stripped away. Proposed biological explanations, such as effects on the clearance of amyloid or on vitamin B12 levels, remain speculative, and the inconsistency across studies is precisely why researchers treat the dementia link as unresolved rather than established.

Why observational studies cannot settle causation

The recurring caveat across this literature is the gap between correlation and cause. Observational studies track people who chose, or were prescribed, a treatment in the real world, so the groups being compared differ in ways that are hard to fully measure. People on long-term acid suppression tend to be older, heavier and managing more chronic illness, any of which can independently raise the risk of kidney decline or cognitive impairment. A systematic review of long-term proton pump inhibitor use that weighed the evidence on kidney disease, dementia and fractures concluded that while several studies showed statistically significant associations, many were limited by confounding and bias, and it stopped short of declaring the drugs a proven cause of any of those outcomes. Only a randomized trial could isolate the drug’s effect, and the long timelines involved make such trials difficult to run.

The case for reviewing rather than fearing the prescription

The practical message that specialists draw from the data is moderation, not alarm. For people with a clear medical need, such as bleeding ulcers or severe reflux, the benefits of proton pump inhibitors are well documented and generally outweigh the uncertain long-term risks. The concern centers on the large share of users who continue the drugs by inertia, long after the original reason has faded, or who take them for mild symptoms that lifestyle changes or lower-intensity medicines could address. Periodic reassessment of whether the prescription is still justified, using the lowest effective dose for the shortest necessary time, is the approach that emerges from the research. That leaves the association intact as a reason for vigilance while acknowledging that the pills remain valuable when they are genuinely needed.

This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.

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