Midlife dementia risk scores in a multi-ethnic population in the Netherlands: the HELIUS study

Background: Migrant populations in the Netherlands may face greater dementia risk factor burden than Dutch natives. Objectives: To study whether midlife dementia risk scores differ by ethnicity. Methods: We calculated three validated dementia risk scores in participants aged 40-70 years of Dutch (n = 2978), South-Asian Surinamese (n = 2084), African Surinamese (n = 3135), Ghanaian (n = 1699), Turkish (n = 2000), and Moroccan (n = 2025) background, from the HELIUS study (Amsterdam, the Netherlands): Cardiovascular Risk Factors, Aging and Incidence of Dementia (CAIDE), LIfestyle for BRAin Health (LIBRA), and Australian National University-Alzheimer's Disease Risk Index (ANU-ADRI). We cross-sectionally compared scores between ethnicities using linear regression. Results: Ethnic minority groups had higher risk scores than those with a Dutch background (CAIDE: +0.66-1.35; LIBRA: +0.66-1.43; ANU-ADRI: +2.75-7.25). CAIDE estimated an absolute 20-year incident dementia risk of 2.6% for Dutch, 3.4% for South-Asian Surinamese, 3.6% for Turkish, 3.7% for Moroccan, 3.7% for African Surinamese and 4.5% for Ghanaian populations. Differences were greater when removing age from scores (CAIDE +0.89-2.22; ANU-ADRI +3.03-8.20), implying that this higher risk score is independent of age. Conclusion: Migrant populations had higher dementia risk scores than Dutch natives. Validation of these scores in migrant populations is warranted. If replicated, ethnicity should be considered when estimating dementia risk and developing preventive strategies for high-risk populations.