Dementia Risk Factors in South Asian Americans: A Unique Picture

Research suggests that the risk factors for Alzheimer’s disease and other dementias differ across populations, with South Asian Americans facing distinct challenges. A review in Alzheimer’s & Dementia analyzed 25 years of research on dementia prevalence and risk factors in India. It found that South Asians may have a unique set of genetic, lifestyle, and health-related risks compared to those of European descent.

Scientists from Rutgers University’s Krieger Klein Alzheimer’s Research Center highlighted the underrepresentation of South Asians in Alzheimer’s research. This lack of focus creates gaps in understanding the disease’s development within this community. Michal Schnaider Beeri, the study leader, emphasized the absence of specific studies on brain health for aging South Asians in the U.S. This gap makes it difficult to compare available evidence with studies from India and other South Asian nations due to impacts of immigration and acculturation.

Despite these shortcomings, Beeri posited that South Asian Americans could reduce dementia risk significantly by managing cardiometabolic health. Key targets should include diabetes and hypertension control, as well as addressing vision and hearing loss, physical and mental activity, and social connections. The researchers reviewed studies in India from 2000 to 2025, aligning findings with 14 modifiable risk factors for dementia identified by the 2024 Lancet Commission. These factors, such as diabetes and physical inactivity, could account for up to 45% of global dementia cases if managed effectively.

Diabetes and metabolic issues appear critical for South Asians. Notably, diabetes develops at younger ages and lower body weights in this group compared to others. According to Beeri, vascular and metabolic risks emerge early in life and may influence dementia risk more than commonly recognized. Unlike other populations where type 2 diabetes stems from insulin resistance linked to obesity, South Asians tend to experience a variant marked by relative insulin deficiency. This form often appears earlier and progresses swiftly from prediabetes to full disease.

Researchers also found education influences dementia risk significantly. In India, limited education contributes to 22% of modifiable dementia risk, compared to 8% globally. Adults lacking formal schooling were over three times more likely to develop dementia than those with a primary education. Additionally, untreated vision and hearing impairments are widespread. Vision loss may cause about 14% of dementia cases in India, and hearing loss is associated with a 59% higher dementia risk.

The role of genetics in dementia risk appears less significant among South Asians compared to Europeans. Findings have spurred the development of the South Asian Middle Age Risk Tracking for Brain Health (SAMARTH) study. Led by Rutgers, SAMARTH follows South Asian adults in the U.S. to identify specific risk and protective factors for Alzheimer’s and related dementias. Beeri explained that the study aims to fill research gaps and inform targeted dementia prevention and treatment strategies.