Association Between Ambulatory 24-Hour Blood Pressure Levels and Cognitive Performance: A Cross-Sectional Elderly Population-Based Study

Relationship between blood pressure variability and cognitive function in geriatric hypertensive patients with well-controlled blood pressure

BACKGROUND

Hypertension is an important risk factor for cardiovascular diseases and cognitive function. Blood pressure (BP) variability has been associated with cognitive dysfunction, but data are sparse regarding the relationship between BP variability and cognitive function in geriatric patients with well-controlled BP.

AIM

The aim of this study was to demonstrate the relationship between blood pressure variability and cognitive functions in geriatric hypertensive patients with well-controlled BP.

METHOD

We analyzed 435 hypertensive patients (167 male, 74.9 ± 8.3; 268 female, 76.1 ± 8.6) treated at least with one antihypertensive drug. All patients underwent ambulatory BP monitoring and the standardized mini mental test (sMMT).

RESULTS

We divided the weighted standard deviation (SD) of systolic BP (SBP) as a measure of BP variability into quartiles. The top quartile group (≥ 18.5 mmHg) had a significantly lower total sMMT score (23.3 ± 3.2, p < 0.001). According to the results of multivariate logistic regression analysis for sMMT, the SD of 24-h SBP was related to sMMT (p = 0.007, 95% confidence interval - 0.301 [- 0.370 to - 0.049]).

DISCUSSION

Although there are some inconsistencies among the studies investigating the relationship between blood pressure variability and cognitive functions in elderly patients, we demonstrated the relationship between increased 24-h blood pressure variability and cognitive functions assessed with sMMT in geriatric population with well-controlled BP.

CONCLUSION

The increased blood pressure variability was associated with poorer cognitive functions in geriatric hypertensive patients with well-controlled blood pressure.

Associations of Pulse and Blood Pressure with Hippocampal Volume by APOE and Cognitive Phenotype: The Alzheimer's Disease Neuroimaging Initiative (ADNI)

BACKGROUND

It is increasingly evident that high blood pressure can promote reduction in global and regional brain volumes. While these effects may preferentially affect the hippocampus, reports are inconsistent.

METHODS

Using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we examined the relationships of hippocampal volume to pulse pressure (PPR) and systolic (SBP) and diastolic (DBP) blood pressure according to apolipoprotein (APOE) ɛ4 positivity and cognitive status. The ADNI data included 1,308 participants: Alzheimer disease (AD = 237), late mild cognitive impairment (LMCI = 454), early mild cognitive impairment (EMCI = 254), and cognitively normal (CN = 365), with up to 24 months of follow-up.

RESULTS

Higher quartiles of PPR were significantly associated with lower hippocampal volumes (Q1 vs. Q4, p = 0.034) in the CN and AD groups, but with increasing hippocampal volume (Q1, p = 0.008; Q2, p = 0.020; Q3, p = 0.017; Q4 = reference) in the MCI groups. In adjusted stratified analyses among non-APOE ɛ4 carriers, the effects in the CN (Q1 vs. Q4, p = 0.006) and EMCI groups (Q1, p = 0.002; Q2, p = 0.013; Q3, p = 0.002; Q4 = reference) remained statistically significant. Also, higher DBP was significantly associated with higher hippocampal volume (p = 0.002) while higher SBP was significantly associated with decreasing hippocampal volume in the EMCI group (p = 0.015).

CONCLUSION

Changes in PPR, SBP, and DBP differentially influenced hippocampal volumes depending on the cognitive and APOE genotypic categories.

"Do it-yourself": Home blood pressure as a predictor of traditional and everyday cognition in older adults

BACKGROUND

Hypertension guidelines recommend home blood pressure (HBP) monitoring in adjunct to office blood pressure (OBP) for its greater reproducibility and prognostic utility in the prevention of cardiovascular outcomes, especially stroke. To date, the relationship between HBP and cognitive function remains unexplored.

METHODS

We examined HBP as a cognitive predictor in a multi-ethnic group of community-dwelling adults aged 60 and over (N = 133) using neuropsychological measures and analyzed the data using multiple regression analyses. We also employed "everyday cognition" measures that have been found to have higher prognostic utility for real-world functioning than traditional cognitive tasks.

RESULTS

Good to perfect HBP monitoring compliance over seven days was achieved by 88.7% of the participants with superior reliability (ICC≥.96) to office readings. Higher home systolic BP and pulse pressure predicted worse processing speed, executive function, and everyday cognitive function, whereas lower home diastolic BP predicted worse everyday cognition. Office readings were similarly associated with everyday cognitive function but with no other cognitive measures.

CONCLUSION

Our findings are the first to validate HBP as a predictor of neuropsychological function in older adults beyond cognitive screening. Differential relationships among blood pressure variables and specific cognitive domains were observed. With proper standardization and training, we demonstrated that HBP can be obtained in a multi-ethnic community-dwelling older adult cohort. Our findings emphasize the importance of employing blood pressure and cognitive measures that are adequately sensitive to detect vascular-related cognitive impairment in a relatively healthy population. Implications regarding proper HBP measurement for hypertension management, cognitive health, and everyday function are discussed.

Eight-year parallel change in baroreflex sensitivity and memory function in a sample of healthy older adults

OBJECTIVES

To examine whether changes in the cardiac autonomic nervous system (ANS) over time, as expressed by baroreflex sensitivity (BRS), were associated with long-term changes in cognitive performance in elderly individuals without dementia.

DESIGN

Community-based 8-year longitudinal study.

SETTING

Clinical settings.

PARTICIPANTS

Individuals aged 66.9 ± 0.9 (N = 425).

MEASUREMENTS

At baseline and follow-up, subjects underwent a clinical interview, autonomic and vascular measurements, and a neuropsychological evaluation including attentional, executive, and memory tests using standardized Z-scores. BRS was defined as being normal, moderate, or severe alteration at each evaluation. On the basis of the longitudinal changes subjects were stratified as being stable, moderate or improved.

RESULTS

Mean attentional, executive, and memory change Z-scores were -0.41 ± 0.9, -0.15 ± 0.7, and -0.14 ± 0.8, respectively. BRS of 56% of the subjects remained unchanged, of 20% decreased, and of 24% improved. After regression analysis, the worsened BRS group was 1.88 times as likely to have greater memory change as the group with stable BRS (P = .02). No significant association was found between longitudinal change in BRS and attentional and executive changes.

CONCLUSION

In healthy elderly individuals, BRS decrease was associated with a weak but significant decrease in memory function. The long-term effect of BRS on memory changes may suggest a role of the ANS in cognitive decline.

Association between ambulatory 24-hour blood pressure levels and brain volume reduction: a cross-sectional elderly population-based study

Previous literature has shown mixed results regarding the association between blood pressure levels and brain volume reduction. The objectives of this study were to determine whether high blood pressure levels were associated with focal brain volume reduction and whether high blood pressure-related focal brain volume reduction was associated with a decline in executive function performance. On the basis of a cross-sectional design, 24-hour ambulatory blood pressure measurements, as well as brain morphology from 3-dimensional magnetic resonance images, were assessed among 183 participants (mean, 65 ± 0.6 years; 62.4% women). Average levels of systolic and diastolic blood pressures, as well as dip, pulse pressure, and mean arterial blood pressure, were used as outcomes. Cortical gray and white matter volumes were determined by automatic calculation using Statistical Parametric Mapping segmentation. Folstein's Mini-Mental State Examination, digit span, part B of Trail Making, and Stroop tests were used to assess executive function performance. Sex, use of antihypertensive drugs, duration of hypertension, leukoaraiosis, body mass index, education level, and total brain matter volume were used as potential confounders. A significant blood pressure-related decrease in gray matter volume of the left supplementary motor areas (Brodmann area 6) and of the left superior and middle frontal gyrus (Brodmann area 8) was shown. No significant decrease was found with white matter volume. Blood pressure-related decreases in gray matter volume were significantly associated with a decline in executive function performance. The association of high blood pressure with brain volume reduction may in part explain blood pressure-related cognitive decline leading to dementia.

Diabetes, impaired fasting glucose, and cognitive decline in a population of elderly community residents

BACKGROUND AND AIMS

Diabetes and impaired fasting glucose, as well as cognitive impairment, are common in the elderly. Although several cross-sectional studies have demonstrated the influence of diabetes on cognitive impairment, only a few longitudinal studies have assessed the relationship between diabetes, impaired fasting glucose and cognitive decline in non-demented elderly community dwellers, by means of extensive neuropsychological batteries. The present study assesses the relationship between baseline diabetes, impaired fasting glucose (IFG) and 2- year evolution of memory, attention and executive performance in a sample of non-demented elderly subjects.

METHODS

DESIGN

Population-based cohort study [(PROgnostic indicator OF cardiovascular and cerebrovascular events (PROOF)].

PARTICIPANTS

One hundred and sixty-three community dwellers aged 65 years without dementia at recruitment.

MAIN OUTCOME MEASURES

Memory, attention and executive performance.

RESULTS

A significant association was observed between baseline diabetes mellitus and a higher 2-year decline in the Trial Making Test B and Stroop test exploring attention and executive function. This effect remained significant after adjusting for age, gender, education, anxiety and depressive symptoms, as well as other cardiovascular risk factors (F=2.41; p=0.007). Instead, no relationship was observed between IFG and cognitive decline.

CONCLUSIONS

Our study showed that, in a sample of elderly non-demented community dwellers, diabetes mellitus (but not IFG) is associated with a higher decline in selective attention and executive functioning. These results emphasize the importance of detecting and man- aging diabetes and impaired fasting glucose, in order to prevent cognitive impairment and dementia.