Female sex, early-onset hypertension, and risk of dementia.

OBJECTIVE: To evaluate the association of early-adulthood and mid-adulthood hypertension with dementia in men and women. METHODS: We evaluated 5,646 members of a diverse integrated health care delivery system who had clinical examinations and health survey data from 1964 to 1973 (mean age 32.7 years; early adulthood) and 1978-1985 (mean age 44.3 years; mid-adulthood) and were members as of January 1, 1996 (mean age 59.8 years). Hypertension categories based on measurements of blood pressure (BP) and change in hypertension categories between the 2 examinations (e.g., onset hypertension) were used to predict dementia incidence from January 1, 1996, to September 30, 2015. Cox proportional hazard models were adjusted for demographics, vascular comorbidities, and hypertension treatment; inverse probability weighting accounted for differential attrition between first BP measurement and start of follow-up. RESULTS: A total of 532 individuals (9.4%) were diagnosed with dementia. Early adulthood hypertension was not associated with dementia, though effect estimates were elevated among women. Mid-adulthood hypertension was associated with 65% (95% confidence interval [CI] 1.25-2.18) increased dementia risk among women but not men. Onset of hypertension in mid-adulthood predicted 73% higher dementia risk in women (95% CI 1.24-2.40) compared to stable normotensive. There was no evidence that hypertension or changes in hypertension increased dementia risk among men. CONCLUSIONS: Though midlife hypertension was more common in men, it was only associated with dementia risk in women. Sex differences in the timing of dementia risk factors have important implications for brain health and hypertension management.

Vitamin D Status and Rates of Cognitive Decline in a Multiethnic Cohort of Older Adults.

IMPORTANCE: Vitamin D (VitD) deficiency is associated with brain structural abnormalities, cognitive decline, and incident dementia. OBJECTIVE: To assess associations between VitD status and trajectories of change in subdomains of cognitive function in a cohort of ethnically diverse older adults. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal multiethnic cohort study of 382 participants in an outpatient clinic enrolled between February 2002 and August 2010 with baseline assessment and yearly follow-up visits. Serum 25-hydroxyvitamin D (25-OHD) was measured, with VitD status defined as the following: deficient, less than 12 ng/mL (to convert to nanomoles per liter, multiply by 2.496); insufficient, 12 to less than 20 ng/mL; adequate, 20 to less than 50 ng/mL; or high, 50 ng/mL or higher. Subdomains of cognitive function were assessed using the Spanish and English Neuropsychological Assessment Scales. Associations were evaluated between 25-OHD levels (as continuous and categorical [deficient, insufficient, or adequate]) and trajectories of cognitive decline. MAIN OUTCOMES AND MEASURES: Serum 25-OHD levels, cognitive function, and associations between 25-OHD levels and trajectories of cognitive decline. RESULTS: Participants (N = 382 at baseline) had a mean (SD) age of 75.5 (7.0) years; 61.8% were women; and 41.4% were white, 29.6% African American, 25.1% Hispanic, and 3.9% other race/ethnicity. Diagnosis at enrollment included 17.5% with dementia, 32.7% with mild cognitive impairment, and 49.5% cognitively normal. The mean (SD) 25-OHD level was 19.2 (11.7) ng/mL, with 26.2% of participants being VitD deficient and 35.1% insufficient. The mean (SD) 25-OHD levels were significantly lower for African American and Hispanic participants compared with white participants (17.9 [15.8] and 17.2 [8.4] vs 21.7 [10.0] ng/mL, respectively; P < .001 for both). The mean (SD) 25-OHD levels were similarly lower in the dementia group compared with the mild cognitive impairment and cognitively normal groups (16.2 [9.4] vs 20.0 [10.3] and 19.7 [13.1] ng/mL, respectively; P = .006). The mean (SD) follow-up was 4.8 (2.5) years. Rates of decline in episodic memory and executive function among VitD-deficient (episodic memory: ß = -0.04 [SE = 0.02], P = .049; executive function: ß = -0.05 [SE = 0.02], P = .01) and VitD-insufficient (episodic memory: ß = -0.06 [SE = 0.02], P < .001; executive function: ß = -0.04 [SE = 0.02], P = .008) participants were greater than those with adequate status after controlling for age, sex, education, ethnicity, body mass index, season of blood draw, vascular risk, and apolipoprotein E4 genotype. Vitamin D status was not significantly associated with decline in semantic memory or visuospatial ability. Exclusion of participants with dementia did not substantially affect the associations between VitD status and rates of cognitive decline. CONCLUSIONS AND RELEVANCE: Low VitD status was associated with accelerated decline in cognitive function domains in ethnically diverse older adults, including African American and Hispanic individuals who exhibited a high prevalence of VitD insufficiency or deficiency. It remains to be determined whether VitD supplementation slows cognitive decline.

Low folate status is associated with impaired cognitive function and dementia in the Sacramento Area Latino Study on Aging.

BACKGROUND: Low folate status is associated with poor cognitive function and dementia in the elderly. Since 1998, grain products in the United States have been fortified with folic acid, which has reduced the prevalence of folate deficiency and hyperhomocysteinemia. OBJECTIVE: We investigated whether folate status is associated with cognitive function and dementia in a cohort of elderly Latinos (aged >or= 60 y; n = 1789) exposed to folic acid fortification. DESIGN: Global cognitive function was assessed by the Modified Mini-Mental State Examination (3MSE) and specific cognitive functions by cross-culturally validated neuropsychological tests. Dementia was diagnosed according to the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, 3rd edition revised, and California Alzheimer Disease Diagnostic and Treatment criteria. Red blood cell (RBC) folate was measured by automated chemiluminescence and total plasma homocysteine by HPLC. RESULTS: The prevalence of folate deficiency (RBC folate

Homocysteine and cognitive function in the Sacramento Area Latino Study on Aging.

BACKGROUND: Elevated plasma homocysteine (hyperhomocysteinemia), an independent risk factor for vascular disease, has been reported to be inversely correlated with objective measures of cognitive function in patients with Alzheimer disease and in community-dwelling older adults. OBJECTIVE: We evaluated the cross-sectional relation between total plasma homocysteine concentration and cognitive function in elderly Latinos (aged > or = 60 y; n = 1789) participating in the Sacramento Area Latino Study on Aging. DESIGN: Global cognitive function was assessed by using the Modified Mini-Mental State Examination, and specific cognitive functions were assessed by using 6 instruments developed for cross-cultural and multilingual neuropsychological evaluation of older persons. Associations between the cognitive function scores and total plasma homocysteine concentrations were then measured by multiple regression analysis with control for potential confounding by nutrient status (red blood cell folate, plasma vitamin B-12), kidney function (serum creatinine), demographic variables (age, sex, education, acculturation), and depressive symptoms. RESULTS: Modest inverse associations were found between homocysteine concentrations and several indexes of cognitive function, including the global Modified Mini-Mental State Examination assessment and the picture-association, verbal attention-span, and pattern-recognition tests (P < or = 0.05). Demographic variables, particularly age and education, were more strongly associated with cognitive function scores than was homocysteine. CONCLUSIONS: Homocysteine is a modest independent predictor of cognitive function in community-dwelling elderly Latinos. Reducing plasma homocysteine concentrations by administering B-vitamin supplements may provide some protection against cognitive decline in this and other elderly populations, but the effect may be limited.