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Associations between late‐life cardiometabolic risk factors and dementia
Author(s) -
Ren Dianxu,
Lopez Oscar L,
Lingler Jennifer H,
Conley Yvette
Publication year - 2021
Publication title -
alzheimer's and dementia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.713
H-Index - 118
eISSN - 1552-5279
pISSN - 1552-5260
DOI - 10.1002/alz.053041
Subject(s) - dementia , medicine , hazard ratio , proportional hazards model , overweight , diabetes mellitus , gerontology , confidence interval , obesity , cohort , body mass index , demography , endocrinology , disease , sociology
Abstract Background Late‐life cardiometabolic risk factors (overweight/obesity, hypertension, hypercholesterolemia, and diabetes) have been inconsistently reported to associate with dementia, with both increased and decreased risks. The purpose of this study was to examine such associations with incident dementia using the large national dataset from National Alzheimer’s Coordinating Center (NACC). Method We used NACC dataset from 2005 to December 2020 and restricted our analysis to patients who were 65 years and older at initial visit, had an APOE genotype available, first visit with dementia free and had a minimum of one follow‐up visit. The cardiometabolic risk factors were measured at initial visit. Piecewise multivariable Cox proportional hazard models accounting for non‐proportional hazards were performed to examine the associations of the 4 cardiometabolic risk factors with incident dementia, controlling for age, gender, race, education and APOE genotype. Adjusted hazard ratio (aHR) and 95% confidence interval (CI) were reported. Result For the defined cohort (N=13,068), mean age at enrollment was 74.9 years, participants were more female (59%), and non‐Hispanic white (76.9%). Over an average of 4.8 years follow‐up, 2817 (21.6%) developed dementia. Both diabetics and hypertension demonstrated the increased risk of dementia compared to non‐diabetics (aHR=1.26, 95% CI (1.12, 1.41), P<0.0001), and to non‐hypertension (aHR=1.09, 95% CI (1.01, 1.19), P=0.026). However, hypercholesterolemia was not associated with dementia (aHR=1.03, 95% CI (0.95, 1.11), P=0.65). Differential BMI effects on incident dementia were observed over the length of follow‐up before dementia diagnosis. During the time of 0‐4 years and 4‐8 years before dementia, increased BMI significantly associated with reduced risk of dementia [aHR=0.96, 95% CI (0.95‐0.97), P<0.001; aHR=0.98, 95% CI (0.96‐0.99), P=0.016], and no effect during the time of 8‐12 years (aHR=0.99, 95% CI (0.96‐1.02), P=0.54). However, for the time longer than 12 years before dementia, higher BMI exhibited a trend of increased risk of dementia (aHR=1.05, 95% CI (0.99‐1.10), P=0.08). Conclusion Our analyses showed baseline diabetes and hypertension in late‐life are associated with dementia. The BMI‐dementia association likely attribute to a harmful effect of higher BMI with the onset of dementia over a long follow‐up and a potential reverse‐causation effect when the follow‐up is short.