More people are dying from dementia, according to new study

Deaths from dementia have tripled in just 21 years, according to a new study published in The Primary Care Companion for CNS Disorders.

In 1999, about 150,000 Americans died from dementia, according to the study. By 2020, that number had tripled to over 450,000.

The chances of dying from dementia increased among every demographic group studied, according to study author Mohsan Ali, a physician with the King Edward Medical University in Pakistan.

Tripling of dementia deaths

Dementia is defined by the National Institute on Aging as "the loss of cognitive functioning — thinking, remembering, and reasoning — and behavioral abilities to such an extent that it interferes with a person's daily life and activities." The reason it is increasingly the cause of death could be because people are living longer or getting diagnosed earlier, according to Ali.

"Age is the most significant risk factor for dementia," Ali said. However, the increased prevalence of chronic conditions such as heart disease, diabetes, and obesity may also be contributing factors, he added.

Women, Black adults, and people living in rural communities showed the greatest increase in dementia deaths, the study found.

"While the increased rates in women may be because women live longer than men, there may be biological and genetic factors that make women more susceptible to dementia," Ali noted. "Rural areas face a higher burden of dementia-related mortality due to several factors. These include limited access to healthcare services, fewer specialists in dementia care, and reduced availability of support services."

Black adults had the highest death rate, followed by non-Hispanic white adults, and then Hispanic adults.

Fresh insights on dementia prevention

By 2050, the number of people with dementia will double in the U.S. to over 10.5 million and triple globally to over 150 million, the British medical journal The Lancet forecast in 2022. Yet despite these alarming statistics, experts say the average person has some control over their cognitive health.

"I am most excited about advances in dementia prevention, because we are learning about a number of lifestyle modifications that are both accessible to most of us and effective," Leah Croll, MD, neurologist at Maimonides Health in New York, told ABC News.

Up to 45% of dementia cases may be preventable by addressing 14 modifiable risk factors, according to the Lancet Commission on Dementia.

Lifestyle factors that increased the chances of a dementia diagnosis include less education, head injury, physical inactivity, smoking, excessive alcohol consumption, high blood pressure, obesity, diabetes, high cholesterol, hearing loss, depression, social isolation, vision loss, and exposure to air pollution in older life.

"Staying up-to-date with your primary care visits, being diligent about your medications pays dividends over and over for your brain health," Croll emphasized.

Dementia diagnosis and treatment today

Early detection and diagnosis is key to addressing dementia, according to experts.

Dementia is generally diagnosed with a combination of cognitive testing, brain imaging, and sampling the cerebrospinal fluid (CSF) that surrounds the brain and spinal cord and checking it for levels of dementia-related proteins.

Because some of these tests may not be readily available in some areas and can be expensive, researchers have been working on more accessible screening methods. For example, a recent study found that a blood test for Alzheimer's disease, which is the most common type of dementia, may be as accurate at detecting Alzheimer disease as CSF sampling. However, the blood test is still in early phases of study.

In addition to ongoing research for diagnostics, there are new FDA-approved treatments for early Alzheimer's dementia, when the symptoms are still relatively mild.

"Right now, it seems that these drugs modestly slow down the progression of disease, but they do not stop it, so it's unclear how they will impact morbidity and mortality," Croll cautions.

Overall, Croll believes that patients and families affected by dementia should feel hopeful about the future: "In many ways, dementia is one of the final frontiers in medicine, and we are finally starting to crack the code," she said.

Noor Shaik, MD, PhD, is a neurology resident physician and a member of the ABC News Medical Unit.