- Adolescents and young adults with diabetes may be at higher risk of Alzheimer’s disease later on, according to a new study.
- The findings suggest that younger people with type 1 or type 2 diabetes are at an elevated risk of the neurodegenerative disease.
- The study aligns with increasing evidence showing a link between diabetes and Alzheimer’s.
- Diabetes is already understood to be a risk factor for Alzheimer’s.
With rates of obesity rising in the United States and globally, the prevalence of diabetes is expected to follow, with the disease affecting more young people.
Previous research has found that people over 40 who have these biomarkers are 60–80% more likely to develop dementia or Alzheimer’s.
A new study finds that biomarkers that have been associated with the development of Alzheimer’s disease (AD) (AD) later in life are present in people who have youth-onset type 1 and type 2 diabetes.
The authors of the study observed Alzheimer’s-linked blood plasma biomarkers, as well as elevated amyloid protein levels in brain areas associated with Alzheimer’s in adolescents and young adults with diabetes.
This research is the first to investigate the presence in adolescents and young adults of these potential pre-clinical signs of Alzheimer’s. The study was recently published in Endocrines.
“There are a growing number of studies investigating how diabetes pathophysiology might contribute to Alzheimer’s Disease and dementia,” said first study author, Allison L. Shapiro, MD, MPH, assistant professor of Pediatric Endocrinology at the University of Colorado.
“The leading hypotheses include insulin dysregulation (e.g., insulin resistance and impaired insulin secretion) and hyperglycemia,” she told Medical News Today.
The authors of the present study note that previous studies have found that, compared to those without diabetes, people with adult-onset diabetes are 60–80% more likely to develop dementia or Alzheimer’s.
For the new study, researchers at the University of Colorado’s Anschutz Medical Campus analyzed data from the SEARCH cohort.
Within this cohort, 25 people had type 1 diabetes and 25 had type 2 diabetes. The youngest group had a mean age of 15 years, while the young adults were around 27 years old. Of the entire group, 59% were female.
A healthy control group provided a basis for comparison. This consisted of 25 adolescents just shy of 15 years of age, and 21 young adults with a mean age of around 25.
Blood plasma from the SEARCH cohort was analyzed for the presence of Alzheimer’s biomarkers. In addition, seven people with diabetes from the cohort were recruited for the new study along with six control individuals to receive PET brain scans.
It was observed that people with youth-onset diabetes had higher levels of blood biomarkers that are associated with Alzheimer’s.
The scans revealed the presence of amyloid and tau densities — both associated with Alzheimer’s — in Alzheimer’s-related brain regions among those with the biomarkers. However, these differences didn’t research statistical significance.
Shapiro said the study was too small to determine if one type of diabetes carries a higher risk than the other.
“We will need larger numbers of people and longer follow-up time to fully address this question,” she said.
It is also not yet known if a person with youth-onset diabetes would continue to exhibit the Alzheimer’s-related biomarkers as they age.
“Other studies in older adults who developed diabetes in adulthood have shown similar trends to what we found in our young adults with youth-onset diabetes,” Shapiro said.
“Together with the adult data, we would hypothesize that the trends we observe in young adulthood will persist into later life.”
Courtney Kloske, PhD, director of scientific engagement at the Alzheimer’s Association, not involved in the study, pointed out that both Alzheimer’s and diabetes are complex diseases.
“Research suggests that they share some similar underlying mechanisms, such as impairments in the energy production of certain cells,” Kloske told MNT.
Kloske noted that diabetes and cardiovascular issues such as hypertension, and cholesterol problems are risk factors for cognitive impairment and dementias, including Alzheimer’s.
Kloske cautioned against viewing the study as definitive, saying it has limitations that mean “we cannot take their findings as conclusively proven, but certainly as worthy of further research.”
She said the study was too small and preliminary “to test an idea that early onset diabetes may begin a series of changes in the brain that eventually lead to cognitive decline and/or dementia.”
“Although research is accelerating in diabetes and Alzheimer’s disease, currently, the information is still limited about what exactly about diabetes contributes to higher risk of Alzheimer’s disease and dementia,” Shapiro said.
“In folks with diabetes, continued management of blood sugar is good practice to prevent diabetes complications. This practice may also help to prevent higher risk of cognitive issues due to Alzheimer’s disease and dementia.”
— Allison L. Shapiro, MD, MPH, first study author
The most immediate action that can be taken for high-risk individuals is partaking in regular cognitive screenings to track the progression of and dementia or Alzheimer’s.
“Risk factors for Alzheimer’s and other dementia occur across the entire life course,” Kloske said.
“The earlier we can detect brain changes and intervene, and the longer we can practice brain-healthy behaviors, the better,” she added.
Kloske noted that the Alzheimer’s Association provides guidance for brain health, emphasizing the following health and lifestyle recommendations:
- getting regular physical activity
- managing diabetes and blood pressure
- being smoke-free
- sleeping well
- following a healthy balanced diet
Kloske also cited the Study to Protect Brain Health Through Lifestyle Intervention to Reduce Risk, known as U.S. POINTER.
This is a two-year clinical trial, she explained, “to evaluate whether lifestyle interventions that simultaneously target multiple risk factors can protect cognitive function in older adults (age 60-79) at increased risk for cognitive decline.” Data and results of the trial are expected in 2025.