Blood pressure variability and cognitive function in older hypertensives

Association Between Blood Pressure Variability With Dementia and Cognitive Impairment: A Systematic Review and Meta-Analysis

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Blood Pressure Variability and Cognitive Function Among Older African Americans: Introducing a New Blood Pressure Variability Measure

BACKGROUND

Although blood pressure (BP) variability has been reported to be associated with cognitive impairment, whether this relationship affects African Americans has been unclear. We sought correlations between systolic and diastolic BP variability and cognitive function in community-dwelling older African Americans, and introduced a new BP variability measure that can be applied to BP data collected in clinical practice.

METHODS

We assessed cognitive function in 94 cognitively normal older African Americans using the Mini-Mental State Examination (MMSE) and the Computer Assessment of Mild Cognitive Impairment (CAMCI). We used BP measurements taken at the patients' three most recent primary care clinic visits to generate three traditional BP variability indices, range, standard deviation, and coefficient of variation, plus a new index, random slope, which accounts for unequal BP measurement intervals within and across patients.

RESULTS

MMSE scores did not correlate with any of the BP variability indices. Patients with greater diastolic BP variability were less accurate on the CAMCI verbal memory and incidental memory tasks. Results were similar across the four BP variability indices.

CONCLUSIONS

In a sample of cognitively intact older African American adults, BP variability did not correlate with global cognitive function, as measured by the MMSE. However, higher diastolic BP variability correlated with poorer verbal and incidental memory. By accounting for differences in BP measurement intervals, our new BP variability index may help alert primary care physicians to patients at particular risk for cognitive decline.

Blood pressure and cognitive function in older adults with cardiovascular disease

BACKGROUND

Past studies link elevated blood pressure (BP) and BP variability to adverse neurocognitive changes in community samples. However, little is known about the relationship between BP indices and cognitive function in older CVD patients.

METHODS

A total of 99 older adults with CVD completed a comprehensive neuropsychological test battery. Resting BP measurements were collected every 10 min for 2 hr during a separate cardiac assessment. Five BP indices were generated: average and standard deviation of systolic blood pressure (SBP), average and standard deviation of diastolic blood pressure (DBP), and a function of systolic variability and average diastolic pressure. We examined the relationship between these BP indices and cognitive function.

RESULTS

Partial correlation adjusting for age and education revealed that the function of systolic variability and average diastolic pressure (SBP standard deviation divided by the average DBP) was most closely related to test performance, showing significant associations to both Learning/Memory (r = 0.25) and Language functioning (r = 0.22). SBP indices were also related to Language functioning (SBP avg., r = 0.22; SBP SD, r = 0.25), though DBP indices were unrelated to performance in any cognitive domain.

CONCLUSIONS

The current findings indicate that BP is modestly related to cognitive function in older CVD patients. Contrary to expectations, greater BP variability was associated with better, not poorer, cognitive test performance. Such findings suggest that the relationship between BP and cognitive function is more complicated than typically believed and requires further examination.

Low ambulatory blood pressure is associated with lower cognitive function in healthy elderly men

INTRODUCTION

Low blood pressure (BP) has been found to be associated with cerebrovascular damage in the elderly. Studies of the relation of ambulatory BP to cognitive function in elderly persons aged 80 years or above is lacking, however.

METHODS

Ninety-seven 81-year-old men from the population study 'Men born in 1914' underwent ambulatory BP monitoring and were given a cognitive test battery, 79 subjects completing all six tests. Low ambulatory systolic blood pressure (SBP) was defined as <130 mmHg and low ambulatory diastolic blood pressure (DBP) as <80 mmHg (corresponding in terms of office BP to approximately <140 and <90 mmHg, respectively). Odds ratios (OR) for lower cognitive function were calculated using a forward stepwise logistic regression model, controlling for confounding factors.

RESULTS

Subjects with ambulatory SBP <130 mmHg had higher OR values for daytime (OR 2.6; P=0.037), nighttime (OR 3.6; P=0.032) and 24h (OR 2.6; P=0.038) BP measurements. A lower cognitive function was associated with lower nighttime SBP and DBP levels and lower 24-h mean SBP compared to subjects with higher cognitive function. OR values connected to low nocturnal SBP, had a tendency to be particularly high among subjects on anti-hypertensive drugs (OR 9.1; P=0.067, n.s.).

CONCLUSION

Ambulatory SBP levels <130 mmHg and lower nighttime SBP and DBP were associated with lower cognitive function in healthy elderly men. Further investigation is needed to ascertain the effects of the presently recommended treatment goal of <140 mmHg for office SBP also on elderly over 80 years of age.

Blood Pressure Variability and Dementia Rating Scale Performance in Older Adults With Cardiovascular Disease

OBJECTIVE

The present study examined the relationship between multiple indices of blood pressure (BP) and cognitive function (as measured by the Dementia Rating Scale).

BACKGROUND

Cardiovascular disease (CVD) is associated with cognitive dysfunction and cerebrovascular pathology in the elderly and is a known risk factor for stroke and Alzheimer disease. Yet, the mechanisms for the effects of CVD on cognitive function are not well understood.

METHODS

Participants were 97 nondemented older adults with CVD who underwent neuropsychologic assessment, and a 2-hour cardiovascular laboratory protocol.

RESULTS

After controlling for age and years of education, results of hierarchical linear regression analyses indicate a significant positive relationship between a function of BP variability (SD of systolic BP divided by the average diastolic BP) and cognitive function (R change=0.042, F (1, 85)=5.434, P<0.05). No relationship emerged between any other BP index and cognitive function.

CONCLUSIONS

Contrary to expectations, greater BP variability was associated with better, not poorer, cognitive test performance. These findings suggest that the relationship between BP and cognitive function is more complicated than originally conceptualized and requires further investigation.

Interactive effects of hypertension and alcohol dependence on the P300 event-related potential in African-Americans

Although hypertension and alcohol dependence have been linked by epidemiological surveys and clinical observations, their interactive effects on brain function have rarely been tested. The present study involved the recording of P300 event related potentials (ERP) from 106 middle-aged African-American adults assigned to one of four groups: normotensive/nondependent (n=56), hypertensive/nondependent (n=11), normotensive/dependent (n=27), and hypertensive/dependent (n=12). The numbers of Nicotine Dependence, Major Depressive Disorder, and Conduct Disorder symptoms were specified as covariates within a 2 by 2 factorial design. ERPs were recorded during separate visual and auditory oddball tasks. The major result was a synergistic effect of hypertension and alcohol dependence on auditory P300 latency: the combination of both factors was associated with greater slowing than the sum of their independent effects. Future studies should continue to examine the potential synergistic effects of alcohol dependence and hypertension with a view toward identifying and reducing neurophysiological decrements and stroke risk among middle-aged patients.