Five things we learned about Alzheimer’s in 2023

There are now three newly approved treatments for Alzheimer’s, with a fourth on the way.

In July 2023, the U.S. Food and Drug Administration (FDA) granted traditional approval for Leqembi for treatment of mild cognitive impairment due to Alzheimer’s and mild Alzheimer’s dementia. This treatment, while not a cure, slows cognitive decline and can give people with early Alzheimer’s more time to maintain their independence.

Back in June 2021, the FDA granted accelerated approval to Aduhelm for the same purpose. At the Alzheimer’s Association International Conference (AAIC) in July 2023, Eli Lilly reported positive results for a third treatment — Donanemab — in that same population. The company expects FDA action in the early part of 2024.

In May, the FDA approved brexpiprazole for agitation in people with Alzheimer’s disease. This is the first FDA-approved treatment for Alzheimer’s-related agitation, which is experienced by about 45% of Alzheimer’s patients. According to research published in May 2023, there are more than 140 therapies being tested that target multiple aspects of Alzheimer’s.

Hearing aids could slow cognitive decline for
at-risk older adults.

In the largest clinical trial to investigate whether a hearing loss treatment intervention can reduce risk of cognitive decline, researchers found that older adults with hearing loss, who were at higher risk of cognitive decline, cut their cognitive decline in half by using hearing aids for three years.

The three-year intervention included use of hearing aids, a hearing “toolkit” to assist with self-management, and ongoing instruction and counseling with an audiologist. Though the positive results were in a subgroup of the total study population, they are encouraging and warrant further investigation. The researchers found that the hearing intervention also improved communication abilities, social functioning and loneliness.

Blood tests for Alzheimer’s are coming soon, and could improve diagnosis and treatment.

Blood tests show promise for improving, and possibly even redefining, how Alzheimer’s is diagnosed in the future. Advancements reported for the first time at AAIC 2023 demonstrate the simplicity — perhaps just a simple finger prick! — and value to doctors of blood-based biomarkers for Alzheimer’s.

These findings are timely with the recent FDA approvals of Alzheimer’s treatments where confirmation of amyloid plaque buildup in the brain and ongoing monitoring are required to receive the treatment.

Blood tests are already being implemented in Alzheimer’s drug trials for further proof of their effectiveness. And they are incorporated into proposed new diagnostic and staging criteria for the disease. Blood tests — once verified, and approved by the FDA — would offer a noninvasive and cost-effective option in identifying blood-based markers for the disease.

First-ever U.S. county-level Alzheimer’s prevalence estimates were reported.

The first-ever county-level estimates of the prevalence of people with Alzheimer’s dementia — in all 3,142 United States counties — were reported at AAIC 2023. For counties with a population of 10,000 or more people age 65 or older, researchers estimate the highest Alzheimer’s prevalence rates are in:

• Miami-Dade County, FL (16.6%)
• Baltimore City, MD (16.6%)
• Bronx County, NY (16.6%)
• Prince George’s County, MD (16.1%)
• Hinds County, MS (15.5%)

The researchers identified certain characteristics that may explain the higher prevalence in these counties, including older average age and higher percentages of Black and Hispanic residents. According to the Alzheimer’s Association, these stats can help public health officials determine the burden on the health care system, and better pinpoint areas of high risk and high need — for example, for culturally-sensitive health support and caregiver training services.

Chronic constipation is associated with poor cognitive function.

Approximately 16% of the world’s population struggles with constipation. That prevalence is even higher among older adults. This year, researchers reported that less frequent bowel movements were associated with significantly worse cognitive function.

Compared to those with bowel movements once daily, people with bowel movements every three days or more had worse memory and thinking equal to three additional years of cognitive aging. These results stress the importance of clinicians discussing gut health, especially constipation, with their older patients, including how to prevent constipation.