The Facts About Statins and Dementia Risk

Here’s what you need to know: the claim that low blood cholesterol—and therefore statin use—causes dementia is not supported by a large body of scientific and clinical evidence. In fact, extensive research shows the opposite is true: that statins are a safe tool for helping prevent cardiovascular disease—which is the leading cause of death in the United States and most parts of the world—and that lower cholesterol levels, and indeed statin use, do not cause dementia and may in fact be associated with reduced dementia risk, not the other way around.

What the research shows

The evidence for statins preventing heart attacks, strokes, and cardiovascular death is overwhelming, coming from decades of rigorous research involving millions of people. What's more, there is ample evidence that these drugs are at worst neutral, and at best beneficial, for brain health.

“In at least 30 studies of lipid-lowering medications, there was no association between these medications and dementia risk. “Multiple randomized trials, large cohort studies, and meta-analyses have not shown that statins or other LDL-lowering therapies increase dementia risk or cause persistent cognitive decline,” says Dr. Alon Gitig, Director of Preventive Cardiology at the Atria Health Institute, “however, many of these studies were not designed with cognition as a primary outcome. Ongoing dedicated trials will further clarify effects.”

Most of these studies followed participants for two to five years, with some extending up to 25 years. Across multiple systematic reviews and meta-analyses, the findings are strikingly consistent: there is no difference in cognitive outcomes—including memory, executive function, or overall cognition—between statin users and non-users. This holds true even among older adults and those taking high doses of statins.

Recently, the largest systematic review and meta-analysis conducted to date evaluated 55 observational studies encompassing a total of 7.7 million people. This study demonstrated the neuroprotective effects of statins. Statin use was associated with a significantly reduced risk of dementia compared to nonusers, for both Alzheimer’s disease and vascular dementia. In addition, longer duration of use (>3 years), and for people with type 2 diabetes mellitus, and populations from Asia, are where the greatest protective effect was observed. Rosuvastatin (a hydrophilic statin) showed a stronger protective effect for all cause dementia with a risk reduction of 28%.

Reflecting this extensive evidence, the United States Preventive Services Task Force and the American Heart Association both strongly recommend statin therapy for appropriate people, and state that fears of statin-induced cognitive dysfunction are unsupported.

Why the confusion persists

So where did the idea that statins harm cognitive health come from? In 2012, the FDA required statin medication labeling that warned of potential cognitive impairment based on case reports, clinical trial data, and adverse event analysis. But here’s the critical context: the FDA noted these effects are reversible and not serious, and that cardiovascular benefits outweigh these small risks.

Some concern also stems from a logical but incomplete understanding of how cholesterol works in the body. The brain uses a lot of cholesterol to support healthy neuron functioning, so when statins lower cholesterol levels in the blood, it seems reasonable to worry they might deprive the brain of this essential substance.

However, as Dr. Gitig explains, “the brain's cholesterol pool is separated from the blood pool.” The blood-brain barrier prevents most cholesterol from crossing from the bloodstream into the brain. “While research is still emerging, the scientific consensus is that the brain receives the vast majority of its cholesterol requirements from synthesis by cells in the mature brain itself,” Dr. Gitig says. “Therefore, the cholesterol content in the brain’s cells would be minimally affected by the level of cholesterol in the blood under normal physiologic conditions.” Many experts also prefer statins that do not cross the blood-brain barrier as readily as others.

Additionally, cholesterol made by brain cells stays around for months to several years, so any changes in brain cholesterol levels caused by a medication should have minimal impact on the brain’s total cholesterol supply.

“From a neurological standpoint, current data do not support statins as a cause of dementia nor a common cause of cognitive decline,” says Dr. David Dodick, a top neurologist and Chief Science and Medical Officer of the Atria Health Institute. “In older adults, studies following large groups show statins generally don't affect thinking or memory, and some research even suggests statin users may have lower rates of dementia—likely because the medications improve blood vessel health, including blood vessels in the brain, and help prevent large and small strokes. While mild and temporary cognitive issues have been reported in studies and by reports to the FDA after their approval, we don’t know precisely how often this actually occurs. Doctors should be aware that this is an uncommon possibility and thoroughly investigate any memory concerns patients report.”

The bottom line

The claim that statins cause dementia is contradicted by decades of rigorous research. While there can be some side effects associated with statins, the cardiovascular and cerebrovascular benefits of statins far outweigh these uncommon, small, and reversible risks, and there’s no credible evidence linking these medications to increased dementia risk.

If you’re taking a statin and concerned about your memory or other side effects, talk with your doctor. Short-term memory loss after starting statins are rare and reversible, and are frequently confounded by the large number of other potential factors that can cause brain fog. Your care team can work with you to determine the cause and adjust your treatment if needed.

For most people, statins remain a powerful tool for preventing heart disease and stroke—and the evidence clearly shows they do so without harming your brain.

— By Abigail Abrams

This article was written in collaboration with Dr. Alon Gitig and medically reviewed by Dr. David Dodick.