Posterior paralimbic and frontal metabolite impairments in asymptomatic hypertension with different treatment outcomes

Abstract

Hypertension is associated with cognitive decline in elderly persons. We studied asymptomatic hypertensive subjects using brain magnetic resonance (MR) spectroscopy to evaluate metabolite impairments before the appearance of symptoms in patients with different treatment outcomes. In all, 14 healthy controls and 37 asymptomatic hypertensive patients (17 controlled and 20 resistant) underwent brain structural MR and MR spectroscopy of the posterior paralimbic (PPL) area and left frontal white matter. Ischemic burden (IB), global cortical atrophy and microbleeds were analyzed with visual scales. Metabolite ratios involving N-acetyl-aspartate (NAA), creatine (Cr), choline (Cho) and myoinositol (mI) were computed. Ultrasound measurements, including intima-media thickness, plaques and hemodynamic ratios, were obtained. Intergroup differences in IB, atrophy and metabolite ratios, and the atrophy and IB relationship were assessed with parametric and nonparametric statistical tests. In addition, the impacts of demographic, analytic and clinical factors, ischemia and atrophy, and ultrasound measurements on metabolite ratios were assessed. The significance level was set at Pp0.05. Higher atrophy scores presented with higher total or frontal IB (Po0.05). However, there was no intergroup difference in atrophy and IB. PPL mI/Cr was increased in resistant hypertension (Po0.021), whereas frontal NAA/Cr (Po0.007) showed opposite trends between controlled (increased ratios) and resistant (decreased ratios) hypertension. Unlike PPL mI/Cr, frontal NAA/Cr showed significant correlations with the lipid profile and ultrasound measurements. PPL mI/Cr increases in resistant hypertension, and frontal NAA/Cr diverges between controlled and resistant hypertension before physical and neuropsychological symptoms appear.

Indirect Effects of Elevated Body Mass Index on Memory Performance Through Altered Cerebral Metabolite Concentrations

“…High levels of mI have been reported in patients with diabetes (41–43) and hypertension (44), conditions closely related to elevated BMI. In the current study, BMI was associated with elevations in mI/Cr even after statistically adjusting for systolic blood pressure, fasting glucose levels, and use of anti-hypertensive or hypoglycemic agents, suggesting that BMI independently accounts for variance in cerebral mI levels in otherwise healthy middle-aged adults.…”

Blood Pressure Responses to Hypertension Treatment and Trends in Cognitive Function in Patients With Initially Difficult‐to‐Treat Hypertension: A Retrospective Subgroup Analysis of the Observational Study on Cognitive Function and SBP Reduction (OSCAR) Study

“…Our retrospective examination of this cohort was motivated by the consideration that sustained high BP despite antihypertensive therapy has potential for adverse longer‐term consequences beyond familiar cardiovascular risk. In particular, increased arterial stiffness in the cerebrovascular circulation may contribute to cognitive decline 7–9 …”

“…In particular, increased arterial stiffness in the cerebrovascular circulation may contribute to cognitive decline. [7][8][9] DTTH was defined for this purpose as BP not satisfactorily controlled despite the use of at least 3 antihypertensive drugs. This was a pragmatic definition chosen to facilitate a retrospective investigation and should not be conflated with current definitions of ''resistant hypertension.''…”

Is There a Specific Pattern of Attention Deficit in Mild Cognitive Impairment with Subcortical Vascular Features? Evidence from the Attention Network Test

“…The imaging exams were reviewed by an expert radiologist (J.M.G.S.) [16]. Based on these results, we classified MCI patients as svMCI when they met the criteria of Frisoni et al [2] and as nvMCI when they were free from vascular brain damage.…”