Aging
Evaluating heterogeneity in the association between hypertension and dementia by age and race/ethnicity in a diverse cohort of Asian American and non-Latino white older adults Natalie Gradwohl* Natalie Gradwohl L. Paloma Rojas-Saunero Yingyan Wu Eleanor Hayes-Larson Yixuan Zhou Rachel Whitmer Paola Gilsanz Ron Brookmeyer Elizabeth Rose Mayeda
Introduction: The association between hypertension and dementia may vary by age, with robust associations between midlife hypertension and higher dementia risk and null or inverse associations between later-life hypertension and dementia risk. However, prior research is inconclusive and has minimal representation of Asian Americans.
Methods: We followed a cohort of 132,180 Kaiser Permanente Northern California members (4,848 Chinese, 4,130 Filipino, 2,786 Japanese, 823 South Asian, and 123,593 non-Latino white) aged 60 years and above at baseline, using electronic health records (EHR) from 2002-2020. Hypertension (yes/no) was defined as a diagnosis in EHR ≥5 years before baseline. We ran Cox-proportional hazards models (time on study as timescale) to calculate hazard ratios (HR) relating hypertension and dementia stratified by baseline age <75 vs. ≥75 years and race/ethnicity. Models were adjusted for baseline age, sex/gender, years of education, and baseline age-hypertension interaction.
Results: Prevalence of hypertension 5 years before baseline was high, ranging from 47% among non-Latino whites to 62% for Filipinos. For those <75 at baseline, rate of dementia was higher in hypertensive vs. non-hypertensive individuals for all groups except South Asians (White HR = 1.33 95% CI [1.26-1.40]; Chinese HR = 1.51 [1.10-2.08]; Filipino HR = 1.64 [1.19, 2.25]; Japanese HR = 1.28 [0.85-1.93]; South Asian HR = 1.03 [0.57, 1.84]). Associations were weaker in those ≥75 years at baseline (Figure).
Discussion: Participants with prevalent hypertension at baseline were more likely to develop dementia over follow-up for all racial/ethnic groups except South Asians, for whom estimates were imprecise; this association was larger for those who were younger at baseline. More data on the health of Asian American older adults is needed to understand risk factors for dementia across different ethnicities.
