Researchers Doug Barthold of the University of Washington and Julie Zissimopoulos of the University of Southern California published the first study to compare multiple types of blood pressure medications and the beneficial effect they may have on different populations. Unlike other studies, they looked at how Alzheimer’s disease risk was reduced across race, ethnicity, and sex.
Their study findings suggest that hypertension management in older adults with a type of anti-hypertensive called ARBs (angiotensin-II receptor blockers) could reduce the risk of Alzheimer’s disease for black women, and white women and men. (The study was inconclusive for black men, and Hispanic men and women).
As of press time there are no medications known to prevent or delay the onset or progression of Alzheimer’s disease. Increasingly, researchers are looking to existing medications, used for treatment of other chronic conditions, to see if they could be repurposed to fight against cognitive decline and lower the risk of Alzheimer’s disease.
There is strong evidence that managing high blood pressure is an important step to lowering the risk of Alzheimer’s disease and that some antihypertensive drugs may be more protective than others.
The research team’s retrospective cohort analysis looked at how different classes of anti-hypertensives are protective against Alzheimer’s disease. They looked at over 1 million Medicare enrollees and found antihypertensive drug types called ARBs, angiotensin-II receptor blockers, such as Valsartan (Diovan), Candesartan (Atisan), and Losartan (Cozar), are more protective than other anti-hypertensives, such as ACE inhibitors and four other classes of drugs.
The team concluded that the results were significant enough to warrant additional observational studies and randomized control trials that include men and women from diverse racial and ethnic groups, to investigate if there is a causal effect.
Alzheimer’s disease is a growing public health problem. Right now over 5 million Americans aged 65 and older are living with Alzheimer’s disease and that number is expected to grow to 7.1 million in 2025, and 13.8 million in 2050. At those levels, even small delays in the onset of Alzheimer’s disease could substantially reduce the financial ($300+ billion in 2010) and caregiving burden (18+ billion hours of care in 2016—over forty percent of which is provided by informal caregivers, often family and friends).
Add to those statistics the fact that there is a higher incidence of Alzheimer’s disease for women and racial and ethnic minorities, who are also more likely to require high intensity care and have unmet care needs, and you have an emerging public health crisis ahead.
Researchers worldwide are looking for solutions to stop or mitigate the impact the disease has on population health. Targeted hypertension treatment could reduce the large, growing, and disparate burden of Alzheimer’s disease on the afflicted individuals, their caregivers, and the health system as a whole.
This study indicates that if there is a choice in anti-hypertensive medications, there is a potential additional benefit for using targeted treatments against Alzheimer’s disease, but that it needs to be confirmed by additional research.
“Alzheimer’s disease is an enormous public health concern and while more than a hundred potential drug treatments are in clinical trials, there are still no treatments available to prevent or slow the progression of the disease. Research is building that AHTs reduce risk of dementia and this study suggests a potential pathway independent of blood pressure effects. All else being equal, for patients who are already being prescribed antihypertensives these findings highlight a potential differential effect on their risk of acquiring Alzheimer’s which a clinician may want to take into account,” said Zissimopoulos who is the director of the aging research program at the USC Schaeffer Center and Vice Dean of Academic Affairs at the USC Price School of Public Policy.
The paper, titled “The association of multiple anti-hypertensive medication classes with Alzheimer’s disease incidence across sex, race, and ethnicity,” was published in the journal PLOS ONE on November 1, 2018 with co-authors Geoffrey Joyce of USC, Whitney Wharton of Emory University, and Patrick Kehoe, University Bristol, UK. This research was supported by the National Institutes of Health (NIH), awards R01AG055401, RC4AG039036-01, P30AG043073-01, K01AG042498, R01HL126804, and R01HL130462