Being Overweight May Be a Protective Factor for Dementia in the Vietnamese Immigrant Population

Higher BMI(Body Mass Index) is associated with an increased risk of dementia and functional frailty. The impact of higher BMI on cognitive and functional decline in the Vietnamese population is not well studied. We sought to evaluate the link between higher BMI and newly diagnosed dementia and functional frailty in Vietnamese immigrants.

Methods:

We reviewed electronic health record data from a Cognitive Assessment Clinic at a community health center and identified 38 community-dwelling Vietnamese patients aged ≥ 55 seen at the clinic 01/2021-08/2021. The mean age(±SD) of this cohort was 72.3(±9.35), and 26 patients were women(W) (men(M) 12). In this study, we administered standardized cognitive assessment tests and assigned the patients with normal results or a diagnosis of MCI(Mild Cognitive Impairment) to the control group and those diagnosed with dementia to the study group. Twenty-three patients(W 16, M 7) were diagnosed with dementia, and 12 patients(W 7, M 5) were diagnosed with MCI. Three patients(W 3) had normal results. We obtained ADLs (activities of daily living) and IADLs (instrumental activities of daily living) to assess function. 4 patients (W 2, M 2) were functionally independent, and 34 patients (W 24, M10) were dependent in their daily activities;14 patients (W 11, M 3) were dependent in ADLs and IADLs, and 20 patients (W 13, M 7) were dependent in IADLs only.

Results:

The mean BMI was 24.3(±2.67) in the dementia group, 25.1(±2.9) in the control group, 24.4(±2.47) in the functional dependence group, and 24.7(±3.23) in the functional independence group. None of the patients in our study had BMI ≥30. 8 patients(W 4, M 4) met the criteria for overweight (BMI = 25 – 29.9) in the dementia group and 10 patients(W 6, M 4) in the control group (RR 0.5976, 95% CI 0.3334 – 1.0533, P=0.0746). The number of patients with overweight in the functional dependence and independence group was 16(W 9, M 7) and 2(W 1, M 1) (RR 0.9877, 95% CI 0.7933 – 1.2296, P=0.9115). Overweight Vietnamese patients have a 41% reduction in risk of dementia (RR 0.5976) compared to those with BMI < 25, and the risk of functional dependence (RR 0.9877) between the two groups is almost identical.

Discussion/Conclusion:

Previous studies have suggested that being overweight is favorable for survival in older adults. Our findings indicate that overweight in mid- and late-life may also be a protective factor for cognitive impairment in the Vietnamese immigrant population. More studies with a larger number of patients in this population are needed to investigate this further.