by Meg Evans Smith
Between five and six million Americans age 65 and older live with dementia, a form of memory loss most often caused by Alzheimer’s disease. Anyone facing their retirement years undoubtedly hopes to avoid similar cognitive decline and the challenges of daily life that often follow. Now, a long-term nationwide study seeks to determine whether statins – a class of cholesterol-lowering drugs – can reduce the risk of dementia in people over 75.
Doctors commonly prescribe statins to their patients with high cholesterol, heart disease and diabetes, and to people who have had a heart attack or stroke. There is some evidence that statins might also lower the risk for dementia and slow its progression, including dementia caused by Alzheimer’s disease. So could people who would not otherwise need a statin start taking one in order maintain good mental and physical health as they age?
To answer that question, researchers at Duke University in Durham, North Carolina and Wake Forest University in Winston-Salem, North Carolina recently launched a study called PREVENTABLE, which will compare the impact of taking a statin vs. not taking one in 20,000 older adults. The effectiveness of statins is well understood in younger patients, but less so in people over 75 – a population often left out of scientific studies.
“This is the largest study exclusively of people age 75 and older comparing statins to a placebo,” explained Karen Alexander, MD, a geriatric cardiologist and professor at Duke University Medical Center, and the lead researcher for PREVENTABLE. “If you live past 75, you’re at higher risk of living into those later years where dementia is fairly common, and we’ve never studied how to prevent that.”
PREVENTABLE aims to find out if older adults on statins can live longer and healthier lives without developing new dementia and the persistent disability that often accompanies memory loss, Dr. Alexander said. Almost all statin studies have involved participants between age 40 and 75, so there is little scientific support for prescribing statins to older adults who don’t have high cholesterol, heart disease or a dementia diagnosis but who might benefit from taking them.
“As physicians we have to take the data we have in younger people and make a guess as to whether a statin is the appropriate treatment or therapy to give to our older healthy patients,” said Raj Shah, MD, a geriatrician and associate professor of family medicine with the Rush Alzheimer’s Disease Center at Rush University in Chicago, and a co-investigator with PREVENTABLE. “We’re hoping to learn one way or another if statins will be beneficial for seniors in maintaining longevity without disability,” he added.
The Link Between Statins and Dementia
Dementia is an overall term for loss of thinking abilities that is often marked by difficulties with memory, speech, problem-solving, emotions and behavior, all of which can impair daily living and independence, according to the Alzheimer’s Association.
Aging does not cause dementia, but as people age they may develop diseases such as diabetes, Alzheimer’s, Parkinson’s, Huntington’s, or multiple sclerosis which can cause abnormal changes in the brain that lead to dementia. Other causes include high cholesterol, high blood pressure, vascular diseases (which affect the circulatory system), strokes, brain injuries, some infections, and even heavy smoking and alcohol use. Reducing the risk for health problems that damage the brain could lower the risk of developing dementia, and that’s where statins might come in to play.
Statins lower cholesterol, a waxy substance produced by the liver that helps build cell membranes, produce hormones such as estrogen and testosterone, and synthesize Vitamin D from sunlight. Too much cholesterol can accumulate in arteries, restricting blood flow and potentially leading to high blood pressure, diabetes, cardiovascular disease, heart attacks, and strokes, including “mini strokes” that can cause a range of memory loss and physical decline referred to as vascular cognitive impairment. Statins also reduce inflammation throughout the body, which may help lower the risk for some of the diseases that lead to dementia, and may even lower the risk for cancer.
A Practical Study in the Age of COVID
The PREVENTABLE study (Pragmatic EValuation of EvENTs And Benefits of Lipid-lowering in OldEr adults) is currently recruiting 20,000 volunteers age 75 and older who are not already taking a statin and who don’t have dementia or heart disease. Participants will be randomly assigned to take either atorvastatin (brand name Lipitor) or a placebo for up to five years, with periodic check-ins to test their memory, thinking, and physical abilities, and to see whether they experience heart attacks or strokes. The study is funded by the National Institute on Aging and the National Heart Lung and Blood Institute, both of which are part of the National Institutes of Health.
PREVENTABLE is a “pragmatic” or practical drug trial, designed to test how effectively a drug like atorvastatin works out in the real world – that is, during routine use at a doctor’s office or in a patient’s own home as they go about their daily life, rather than under the strict controls of an “explanatory” trial, which tests how a drug works under the most ideal conditions. For example, a practical outcome of PREVENTABLE is not whether statins lower cholesterol – that is already well established – but whether participants are living well and independently without new dementia or disability while taking the statin, Dr. Alexander explained.
Participants in PREVENTABLE may never even have to leave home – another practical element of the study. They can complete study assessments on their own time, will receive the drug or placebo through the mail, and can communicate with study researchers by phone or through telehealth (video or e-mail), making it easier for seniors to take part in the study. In the future, the study may arrange for in-home visits to conduct physical function tests and collect blood samples, but for now it is completely virtual because of the pandemic.
Multiple Study Locations in Illinois and the U.S.
PREVENTABLE is being coordinated through 38 medical research institutions associated with the National Patient Centered Clinical Research Network (PCORnet) – a network of health systems around the country that collaborate in clinical research – as well as 51 Veterans Administration medical centers. By working with PCORnet and the V.A., study researchers can more easily monitor each participant’s state of health on the statin or placebo through their electronic health records. For that reason, new and existing patients at any of those facilities will have greater eligibility for participating in the study (for more information and to find a participating study site go to https://preventabletrial.org/).
There are six Chicago-area PREVENTABLE study locations: Rush University Health, University of Chicago, University of Illinois at Chicago, the Jesse Brown V.A. Medical Center in Chicago, and the V.A. medical centers in Hines and North Chicago.
PREVENTABLE Calls on Citizen Scientists
Can statins help improve the aging process? Dr. Shah hopes older adults will consider volunteering for PREVENTABLE to help answer that important question. He refers to participants in this and other studies as “citizen scientists” who make valuable contributions to scientific research with their skills, opinions, wisdom, and life experience.
“It’s a partnership of respect, because we’re all taking something that is unknown and learning together to make something known for a broader group,” he explained. “We have different expertise, but they have lived experience, they have a body they’ve lived in for 75 years, and they’re going to be telling us how that body is doing while they’re in the study.”