Rutgers Researchers Lead Study Tracking Risk Factors for Alzheimer’s Disease and Dementias in South Asian Americans

A new review shows that causes of Alzheimer's and dementia in South Asian populations are understudied and sets the stage for the SAMARTH study at Rutgers.

Diasporas living across the world, such as the large Indian diaspora, are influenced by the food and lifestyle of the countries they end up living in. The new societal factors that they experience, together with the differences in their genetic makeup, often uniquely impact their health outcomes for diseases like Alzheimer's and dementia. Comprehensive risk assessment studies of various diasporas are needed to develop research and policies to address emerging health issues arising out of global population movements.

Researchers at the Krieger Klein Alzheimer's Research Center within the Rutgers Brain Health Institute, reviewed 25 years of data on dementia prevalence and risk factors in India. The findings, published in Alzheimer's & Dementia, paves the way for the South Asian Middle Age Risk Tracking for brain Health (SAMARTH) study at Rutgers, the first research initiative in the United States dedicated to tracking the brain health of South Asian Americans and identifying modifiable risks and protective factors for Alzheimer's Disease and related Dementias.

India has one of the fastest aging populations in the world. According to the 2023 UNFPA India Ageing Report, by 2050, the number of Indians ages 60 and older is expected to reach 340 million, or about 1 in 6 older adults worldwide. This demographic shift brings a rising dementia burden with major socio-economic consequences. "An increasing body of evidence indicates that risk factors for dementia in South Asians differ from those in non-Hispanic White and European ancestry populations, creating a critical need for population-specific research to guide effective prevention and treatment," said Akankshi Oberoi, a researcher at the Krieger Klein Alzheimer's Research Center and lead author of the review.

To evaluate existing evidence and identify gaps in knowledge, Oberoi and colleagues conducted a comprehensive review assessing the status of current research on prevalence and risk factors for dementia in India. The review examined studies conducted in the Indian population between 2000 and 2025 and weighed the conclusions against 14 modifiable risk factors for dementia named by the 2024 Lancet Commission, a group of US and international experts in Alzheimer's and related Dementias assembled by the medical journal The Lancet. The 14 modifiable risk factors identified by the Lancet Commission are important as, addressed together, they could prevent or delay up to 45% of dementia cases worldwide.

Critical, modifiable risk factors for dementia in India identified by the review include:

• Diabetes and metabolic disorders: Unlike other ethnicities, South Asians tend to develop diabetes and other metabolic disorders earlier in life, often at a normal body weight. Diabetes is known to double or even triple the risk of dementia.
• Education: Limited education accounts for 22% of modifiable dementia risk in India versus 8% worldwide. In one study, dementia was more than three times as common among adults with no schooling (12.6%) compared to those with a primary education (3.4%).
• Vision: 3 in 4 Indian adults older than 50 have some form of vision impairment compared to about 1 in 10 in the US. Untreated vision loss accounts for an estimated 14% of dementia cases in India.
• Hearing: Hearing loss affects 41% of adults in India and across studies it is linked to a 59% higher risk for dementia and roughly double the risk for Alzheimer's disease.
• Physical activity: Despite the observation that as little as 35 minutes of physical activity a week is linked to a 41% lower dementia risk, more than half of Indian adults (57%) fall short of recommended activity levels.
• Body weight: Unlike Western nations, where excess weight drives much of the risk, in India, being underweight and undernourished also appears to increase risk of developing dementia.

The researchers found that, as in Western countries, dementia is more common among women in India. Prevalence in India was found to be higher among people in rural areas, most likely because of underdiagnosis of the risk factors contributing to dementia.

Researchers reported that genetic variants associated with dementia in populations of European ancestry appear to play a relatively limited role in increasing the risk for the disease in South Asians. They noted that this could mean that as yet unknown genetic risk factors may contribute to dementia risk among South Asians or, alternatively, modifiable health and environmental risk factors may play a bigger role in the South Asian population.

The researchers concluded that longitudinal research studies that follow the brain health of South Asian individuals over time are necessary. Led by Michal Schnaider Beeri, director of the Krieger Klein Alzheimer's Research Center, the SAMARTH study was designed to fill this research gap.

Researchers involved in the study are enrolling 750 adults ages 45 to 70 throughout New Jersey and surrounding region, home to the largest South Asian community in the country. The pathological changes in the brain that lead to Alzheimer's and dementia begin decades before memory problems appear. By following people through their 40s, 50s and 60s, researchers can identify risks early while there is still time to act and watch how each person's brain health changes with age.

Eligible participants are South Asian adults originating from India, Pakistan, Bangladesh, Nepal, Sri Lanka, Afghanistan, Bhutan or the Maldives and fluent in English. Participants complete comprehensive health and cognitive assessments every 18 months, including lifestyle surveys, cognitive and language evaluations, motor function tasks, blood work, physical and neurological exams and brain imaging, with all participants receiving up to $175 in compensation for their time and participation. The study has recruited approximately 170 participants to date.

"South Asians are underrepresented in Alzheimer's research, meaning there is a lack of tailored information and treatment options for them," said Schnaider Beeri. "The SAMARTH study could lead to personalized treatments, early diagnostic tools, and prevention strategies specifically designed for South Asians."

Researchers are currently recruiting volunteers for the SAMARTH study. Those interested in participating in the study may enroll by filling out a screening form. Call 848-932-8415 or email [email protected] for more information.

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