Hypertension Increases the Probability of Alzheimer’s Disease and of Mild Cognitive Impairment in an Arab Community in Northern Israel

Abstract

Background: We aimed to determine whether vascular risk factors are associated with Alzheimer’s disease (AD) and mild cognitive impairment (MCI) in an elderly Arab population. Methods: An Arabic-speaking team performed a door-to-door survey of consecutive residents aged ≧65 years. We estimated the odds of AD or MCI versus normal controls as a function of age, gender, education and presence of vascular factors by multinomial logistic regression with interactions. Results: Out of 767 subjects (54% men), 444 were cognitively normal, 234 had MCI and 89 had AD. AD was significantly associated with hypertension (p = 0.01; OR = 2.08; 95% CI: 1.18–3.65), age (p < 0.0001; OR = 1.19; 95% CI: 1.14–1.24), female gender (p = 0.0016; OR = 3.06; 95% CI: 1.53–6.15) and education (p = 0.0002; OR = 0.75; 95% CI: 0.65–0.88). MCI was significantly associated with hypertension (p = 0.0042; OR = 1.69; 95% CI: 1.25–2.44), age (p < 0.0001; OR = 1.06; 95% CI: 1.03–1.09) and education (p < 0.0001; OR = 0.76; 95% CI: 0.71–0.83), but not with gender. Conclusions: Hypertension, older age and low education significantly increase the probability of AD and MCI. The effect of hypertension on the odds of AD versus controls is over and above the effects of age, gender and education. For MCI versus controls there is no gender effect, and the effect of hypertension is over and above the effects of age and education.

Role of 20-HETE, TRPC channels, and BKCa in dysregulation of pressure-induced Ca2+ signaling and myogenic constriction of cerebral arteries in aged hypertensive mice

“…Epidemiological studies provide evidence that in addition to the increased prevalence of hypertension in aging, the deleterious cerebrovascular effects of hypertension are also exacerbated in elderly patients, whereas younger subjects appear to be more protected from cerebromicrovascular and neurological damage induced by elevated blood pressure (10,38,54). There is strong evidence showing that in older patients hypertensioninduced microvascular injury not only promotes the development of vascular cognitive impairment (24,29,45) but it also significantly increases the risk (risk ratio ϭ ϳ1.5) for sporadic Alzheimer's disease (25,31), supporting the vascular hypothesis of the disease (11)(12)(13). Although the available human data suggest that advanced age and hypertension have synergistic effects (45), the specific age-related mechanisms through which aging increases the vulnerability of the cerebromicrovasculature to hypertension are not well documented in the literature.…”

Incidence and Risk Profile of Dementia in the Regions of Middle East and North Africa

“…A closer look at existing scant data reveals correct interpretations with this regard. For instance, in Israel-Palestine, although the odds of developing Alzheimer’s from hypertension was reported to be 2.08 (95% CI 1.18–3.65), there were considerably more women in the Alzheimer group than all other control groups when female gender was reported by themselves to be a strong independent risk factor for Alzheimer [17]. Besides this, in Iran as well the risk of dementia due to hypertension remains modest (1.4 times, 95% CI 1.0–2.2) [27].…”

“…Additionally, in case of insufficient incidence information for 2 other MENA countries, Egypt [14, 15] and Israel-Palestine [16, 17], cumulative incidence was estimated by using 2 (earliest-to-latest) prevalence surveys [18] of the same nature, that is, same population and methodological details as much as feasible (Bhalla, unpubl. data).…”

Eprosartan-Based Hypertension Therapy, Systolic Arterial Blood Pressure and Cognitive Function: Analysis of Middle East Data From the Oscar Study

“…Although demographic trends and social practices in the Arab world mean that the impact of dementia is likely to be less marked in the short and medium term than in other regions of the world, measures to limit the risk of developing dementia are self-evidently desirable as a contribution to the health of older persons. 11 Observational data in older Arab men suggest a correlation between higher blood pressure and cognitive impairment, 12 whereas other reports have documented an extensive prevalence of classic cardiovascular risk factors and a rising prevalence of metabolic syndrome in Arab populations. [13][14][15][16][17][18] The possibility of preserving cognitive function coincidentally in conjunction with efforts to reduce hypertension-related cardiovascular risk is therefore an attractive idea and has contributed to interest in the possibility that antihypertensive therapy, particularly ARB therapy targeted at the brain renin-angiotensin system (B-RAS), may have beneficial effects on cognition (see Fournier et al 9 for recent discussions of some possible mechanisms of benefit beyond blood pressure reduction, and Takeda et al 19 for some recent perspectives on the concept of the B-RAS).…”