Starting statins earlier may lower dementia risk in people with diabetes

• A large Danish study found that people who started statins within a year after being diagnosed with type 2 diabetes had a 15% lower relative risk of dementia over 10 years than those who didn't start statins.
• Starting treatment later was also associated with a benefit, but it was smaller — a 10% lower relative risk.
• The study can't prove that statins prevent dementia, but it adds to growing evidence connecting cholesterol, cardiovascular health and long-term brain health.

Statins have been prescribed for decades to prevent heart attacks and strokes. New research suggests that for people with type 2 diabetes, starting them sooner rather than later might have another benefit: a lower risk of developing dementia.

Researchers followed more than 132,000 people in Denmark who developed type 2 diabetes and had not previously taken statins. Those who began statin treatment within one year of their diabetes diagnosis were associated with a 15% lower relative risk of developing dementia over 10 years compared with people who didn't start statins within five years, according to EurekaAlert.

People who started statins between one and five years after their diabetes diagnosis had a 10% lower relative risk.

The study, presented Sunday at the European Society of Cardiology Congress in Munich and published in The Lancet Regional Health – Europe, adds an intriguing new piece to the increasingly important relationship between heart health and brain health, The Guardian said.

But there's a significant qualification.

This was an observational study, not a randomized clinical trial. It can show that people who started statins earlier subsequently developed dementia less often, but it cannot prove that taking the drugs caused the reduction.

Still, the finding is consistent with a growing body of research suggesting that controlling cardiovascular risk factors in middle age could be one of the best tools available for reducing dementia risk later in life.

Why people with diabetes were studied

Researchers focused on type 2 diabetes for a reason.

Diabetes itself is associated with an increased risk of cognitive decline and dementia. People with diabetes also commonly have high levels of LDL cholesterol — the so-called "bad" cholesterol that contributes to plaque buildup inside arteries.

That can affect the brain as well as the heart.

Atherosclerosis can damage or narrow blood vessels supplying the brain, increase the risk of stroke and reduce blood flow to brain tissue.

Statins lower LDL cholesterol and are already widely prescribed to people with diabetes to reduce their risk of heart attack and stroke.

The new question is whether doing so early enough might also help preserve the brain.

"Our study supports the idea that dementia risk is best addressed by targeting several factors at once, and that cholesterol may belong on that list," study presenter Dr. Tummas Ternhamar of Copenhagen University Hospital said in a release to The Guardian.

More than 132,000 patients followed

Researchers used Denmark's extensive national health registries to identify 132,585 people who developed type 2 diabetes between 2006 and 2019 and had not previously used statins.

They divided patients into three groups:

• those who began statins within one year of diagnosis;
• those who began between one and five years afterward; and
• those who didn't begin statins within five years.

Patients were followed for a median of 7.1 years, with some outcomes projected over 10 years.

Overall, 2.7% developed dementia during the follow-up period.

Compared with people who didn't begin statin treatment, early treatment was associated with a 15% lower relative dementia risk. Later treatment was associated with a 10% reduction. Results were similar for men and women.

Researchers used statistical techniques designed to make the observational study resemble a randomized trial as closely as possible, but that doesn't eliminate all potential differences between people who take statins and those who don't.

For example, patients who promptly begin and continue preventive medication may differ from nonusers in other ways that influence their long-term health.

Other studies have been pointing in the same direction

The Danish findings don't stand alone.

A 2025 systematic review examined 55 observational studies involving more than 7 million people and found statin use was associated with a 14% lower risk of dementia overall and an 18% lower risk of Alzheimer's disease. Among people with type 2 diabetes specifically, statin use was associated with a 13% lower dementia risk.

Another large observational study, involving more than 570,000 people in South Korea, found that low LDL cholesterol was associated with substantially lower rates of dementia and Alzheimer's disease. Among people who already had low LDL, statin users showed an additional reduction in dementia risk compared with nonusers.

Not every study has found a protective statin effect, however.

An analysis published last year involving more than 11,000 people with type 2 diabetes found an association between higher LDL cholesterol and dementia or cognitive decline but did not find a statistically significant association between statin treatment itself and reduced dementia risk. The researchers said longer follow-up studies were needed.

That's one reason scientists remain cautious about declaring statins a dementia-prevention drug.

What about claims that statins cause memory problems?

The new findings are particularly interesting because statins have periodically been blamed for exactly the opposite problem.

For years, some patients have worried that aggressively lowering cholesterol might impair memory or cognition. Anecdotal reports of memory problems helped fuel those concerns.

Large reviews haven't borne that out.

The American Diabetes Association's 2026 Standards of Care says randomized trials in which cognitive function was specifically measured found no difference between people taking statins and those taking placebo. Reviews of randomized trials and prospective studies similarly have not found evidence that statins cause cognitive dysfunction or dementia.

The American Heart Association reached essentially the same conclusion in a scientific statement examining aggressive LDL lowering and the brain. It found that the preponderance of evidence does not support claims that lowering LDL with statins causes dementia or cognitive impairment. (professional.heart.org)

And another major piece of evidence arrived just this weekend.

A randomized trial involving nearly 10,000 healthy adults over 70 found statin treatment reduced first major cardiovascular events by about 30%. Importantly, researchers found no statistically significant increase in dementia among people taking statins compared with those receiving placebo.

That doesn't prove statins prevent dementia, but it provides strong reassurance about the longstanding fear that they might cause it.

Cholesterol is becoming part of the dementia-prevention picture

The larger story may be changing ideas about dementia itself.

Alzheimer's disease and other dementias were once often treated as largely unavoidable consequences of aging and genetics.

Increasingly, researchers believe a substantial portion of dementia risk is influenced by factors that can be modified over a person's lifetime.

The 2024 Lancet Commission on dementia identified 14 potentially modifiable risk factors and estimated that addressing them could theoretically prevent or delay nearly 45% of dementia cases. High LDL cholesterol in midlife was among the factors added to the list.

Others include high blood pressure, diabetes, smoking, physical inactivity, hearing loss, social isolation and obesity.

And another study presented at the European Society of Cardiology meeting this weekend reinforces the cardiovascular connection: an intensive blood-pressure intervention reduced dementia incidence by 15% over seven years compared with usual care. (acc.org)

None of this means dementia can always be prevented.

It does suggest that the line separating "heart health" from "brain health" is becoming increasingly difficult to draw.

Why timing could matter

Perhaps the most interesting finding in the Danish study is not simply that statin use was associated with lower dementia risk.

It's that earlier treatment was associated with a greater reduction than later treatment.

That makes biological sense if vascular damage accumulates gradually over decades.

Waiting until someone is elderly to address cholesterol, blood pressure, diabetes and other cardiovascular risks may be less effective than preventing damage beginning in middle age.

Researchers don't yet know whether that's the explanation for the difference observed in this study.

But it fits a broader shift in dementia research toward prevention long before symptoms appear.

As Ternhamar put it, the findings suggest "acting early looks better than acting late."

What this means for consumers

This study isn't a reason to start taking a statin solely to prevent dementia.

It is another reason for people with type 2 diabetes or high cholesterol to take cardiovascular risk seriously and discuss appropriate treatment with their doctor.

Statins already have strong evidence behind them for preventing heart attacks and strokes in people at elevated cardiovascular risk. The possibility that they may also contribute to lower dementia risk would be an additional benefit, not currently the primary reason for prescribing them.

Consumers already taking statins also shouldn't stop because of fears that the drugs cause dementia without discussing it with their clinician. Current evidence doesn't support that concern. (doi.org)

The broader takeaway may be more useful than any particular drug:

What's good for the heart increasingly appears to be good for the brain.

Controlling cholesterol and blood pressure, managing diabetes, exercising, avoiding smoking and addressing other cardiovascular risks may not guarantee that someone avoids dementia.

But mounting evidence suggests those familiar heart-health measures could also improve the odds of keeping the brain healthier as we age.