Hypertension is associated with reduced resting-state medial temporal lobe dynamic network flexibility in older African Americans.
Joshua L GillsDarian A NapoleonMiray BudakBernadette A FaustoMark A GluckSteven K MalinPublished in: Physiological reports (2024)
Hypertension disproportionately affects African Americans and is a risk factor for Alzheimer's disease (AD). We investigated the relationship of blood pressure (BP) with medial temporal lobe (MTL) dynamic network flexibility (a novel AD biomarker) and cognitive generalization in older African Americans. In a cross-sectional study, 37 normotensive (systolic BP <130 mmHg, 82.5% F, 64.4 ± 4.9 years; 14.3 ± 2.1 years of education) versus 79 hypertensive (systolic BP ≥130 mmHg, 79.5% F, 66.8 ± 4.1 years; 14.0 ± 0.2 years of education) participants were enrolled. All participants completed a 10-min resting-state functional magnetic resonance imaging scan to assess MTL dynamic network flexibility and two generalization tasks to assess cognition. Anthropometrics and aerobic fitness (via 6-min walk test) were also determined. There was no difference in BMI (29.7 ± 6.4 vs. 31.9 ± 6.3 kg/m 2 , p = 0.083) or aerobic fitness (15.5 ± 2.6 vs. 15.1 ± 2.6 mL/kg/min; p = 0.445) between normotensive and hypertensive groups. However, normotensive participants had higher MTL dynamic network flexibility compared to hypertensive participants (0.42 ± 0.23 vs. 0.32 ± 0.25 mL, p = 0.040), and this was associated with higher mean arterial blood pressure (r = -0.21, p = 0.036). Therefore, hypertensive older African Americans demonstrated lower MTL dynamic network flexibility compared to their normotensive counterparts independent of BMI and aerobic fitness. Further studies are required to determine how blood pressure mediates AD risk in African Americans.
Keyphrases
- blood pressure
- resting state
- functional connectivity
- physical activity
- hypertensive patients
- heart rate
- magnetic resonance imaging
- body composition
- healthcare
- body mass index
- community dwelling
- computed tomography
- high intensity
- type diabetes
- blood glucose
- heart failure
- risk factors
- weight gain
- mild cognitive impairment
- multiple sclerosis
- metabolic syndrome
- network analysis
- insulin resistance
- single molecule
- atomic force microscopy
- weight loss
- high speed