Which cardiovascular drugs may help lower dementia risk?

The study authors wanted to understand more about how the combination and long-term use of cardiovascular medications affected dementia risk in a more generalized population.

They collected information from the Swedish population via population registers. They used the National Patient Register to identify dementia cases and included 88,065 participants with dementia.

The researchers then matched each dementia participant to 10 controls based on age and sex.

Then, they used data from the Prescribed Drug Register to examine participants’ medications. They specifically looked at the use of:

• oral anticoagulant drugs
• diuretics
• lipid-lowering drugs
• antiplatelets, which prevent blood clots by affecting platelets
• beta-blockers, calcium channel blockers, and renin-angiotensin system-acting agents, which all help lower blood pressure.

They also examined the combination use of these medications. They then divided participants into four groups in terms of medication use: nonusers, users for 1 to 4 years, users for 5 to 9 years, and users for 10 years or more.

The study authors considered participants as exposed to a medication if they picked up the prescription at least twice in one year. They noted that a participant had to have been exposed to a medication for at least 4 years before dementia diagnosis to account for the lag in dementia diagnosis.

Next, researchers used the Total Population Register and National Patient Register to account for covariates like education level, history of numerous cardiovascular problems, history of diabetes, and socioeconomic status.

Based on their analyses, they found that many of the examined medications decreased the risk of dementia if taken for 5 years or longer. They found this true for antihypertensives, lipid-lowering drugs, oral anticoagulants, and diuretics.

However, they found that short-term use of 1 to 4 years of all cardiovascular medication classes was associated with an increased risk for dementia.

The use of antiplatelet medications for any length of time was associated with an increased risk for dementia.

In sensitivity analyses, researchers found that 10 years or more of antiplatelet use was associated with a slight decrease in risk for dementia. However, this result did not reach a level of statistical significance.

Researchers next looked at the combination use of cardiovascular drugs. In these analyses, they excluded participants who took cardiovascular medications for 4 years or less, and any participants using additional medications that were not the focus of the research.

They found that combinations of antihypertensives and combinations of one antihypertensive or more with a diuretic were associated with a lower risk for dementia.

Combining lipid-lowering drugs with one or more antihypertensive was associated with decreased dementia risk. There were similar results for oral anticoagulants combined with antihypertensives.

In the combination analyses, researchers did not find a statistically significant lower risk for dementia associated with lipid-lowering drugs or oral anticoagulants taken alone.

When antiplatelets were paired with at least one antihypertensive, there was no risk association with dementia. When combined with two or more antihypertensives, there was a decreased risk for dementia.

The study does present with limitations. First, it was conducted in Sweden, meaning there may be a need for more diversity with later studies and that the results cannot be generalized to all populations.

It also cannot prove causation, and there is a risk of bias. The researchers acknowledged that the data apply to people who live at least 4 years after starting cardiovascular drugs, rather than individuals who became ill quickly.

It is also possible that researchers missed dementia diagnoses, particularly since they did not have access to primary care data. This could have affected the overall results.

Residual confounding is possible because of other factors, like missed cardiovascular disease diagnoses.

Finally, researchers had to operate under certain assumptions for their research, such as the assumption that participants were taking the medications that they picked up and were prescribed. One author also declared a conflict of interest.

Mimi Lee, MD, a vascular neurologist and clinical neurophysiologist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA, who was not involved in this research offered the following words of caution regarding the study to Medical News Today:

“While the study suggests that heart medications might help protect against dementia by improving blood flow and brain health, it can’t prove cause and effect. It’s based on observational data, meaning other factors, like diet or lifestyle, could be influencing the results. Also, the study only includes people from Sweden, so it may not apply to other populations. It also didn’t include people with severe health problems, which could affect the findings.”

It may be helpful to look more at the potential increased dementia risk associated with short-term use of certain medications, as there could be confounding involved in these scenarios. Additional research will also be helpful to look at the relationship between cardiovascular medications and dementia subtypes.

Future research may see how this data could be applied to dementia treatment. Study author Mozhu Ding, PhD, assistant professor with the Karolinska Institutet, told MNT that “there is a lot more to be done.”

“For instance, there is ongoing research to investigate if certain cardiovascular disease drugs have a direct effect in clearing the enzymes in the brain that is associated with Alzheimer’s diseases, which can be promising for identifying targets for new dementia treatment,” she explained.

Overall, the data adds to understanding regarding cardiovascular disease drugs and how they may affect dementia risk.

Patrick Kee, MD, PhD, a cardiologist with Vital Heart & Vein, who was not involved in this study, noted the following clinical implications of the data:

“This study contributes to our understanding of optimal blood pressure management, particularly in preventing dementia and reducing cardiovascular complications like coronary artery disease, peripheral artery disease, and renovascular disease. While it’s intriguing and surprising to find an association between antiplatelet monotherapy and incident dementia, it’s reassuring to know that antihypertensive therapy may mitigate this potential adverse effect. Moreover, this study reinforces the safety of lipid-lowering drugs, emphasizing that they don’t increase the risk of developing dementia.”

Another concern regarding clinical practice is the study’s findings regarding antiplatelet use. While it does require more research, it may be essential to consider in later clinical practice.

“Antiplatelets stood out as the single drug class that seems to be harmful for cognition,” Ding noted. “Given the widespread use of antiplatelets, it will be important to consider their potential negative cognitive effect when prescribed to patients in need.”