Antihypertensive Treatment in People With Dementia

Antihypertensives in dementia: Good or bad for the brain?

Hypertension is associated with both ageing and dementia. Despite this, optimal blood pressure targets in dementia remain unclear. Both high and low blood pressure are associated with poorer cognition. Changes in vascular physiology in dementia may increase the vulnerability of the brain to hypoperfusion associated with antihypertensives. We discuss the potential risks of antihypertensives in the context of altered cerebral haemodynamics, and evidence from antihypertensive trials in dementia. We suggest that individualised blood pressure targets should be the focus for antihypertensive therapy in dementia, rather than strict control to uniform targets extrapolated from trials in cognitively healthy individuals.

Proxy Decision-Making for Clinical Research in Nursing Home Residents With Dementia: A Qualitative Analysis

OBJECTIVES

The benefit-risk ratio of many interventions remains unclear in older adults with dementia. Efforts for more representative trial inclusion are made; however, recruiting and particularly gaining informed consent remains complex. For research participation, dementia compels the designation of a legal guardian (LG) to give proxy consent. To advance future trial development, we aimed to provide more insights into the factors that affect the proxy decision-making process in dementia research.

DESIGN

A qualitative analysis of semi-structured interviews about proxy decision-making on participation in dementia research.

SETTING AND PARTICIPANTS

LGs of nursing home residents that gave (n = 19) and refrained from giving (n = 18) proxy consent for a clinical trial (the ∗∗∗BLINDED∗∗∗ study) in the Netherlands.

METHODS

Verbatim transcripts were thematically analyzed by using a preliminary deductive framework with room for induction of additional emerging themes, being an overall abductive approach. Based on that theme list, related factors of the decision-making process were grouped into overarching levels and merged into a step-by-step process.

RESULTS

When discussing proxy decision-making on the participation of an older adult with dementia in a clinical trial, LGs described interconnected factors on the level of the study and patient. Past experiences and attitudes of the LG influenced the weighing of these study- and patient-related factors, leading to a preliminary decision. Other proxies and treating health care professionals (HCPs) were named as important other stakeholders of the decision-making process.

CONCLUSIONS AND IMPLICATIONS

When giving proxy consent for research participation, LGs weigh study- and patient-related factors, leading to an initial benefit-risk evaluation. This weighing process is influenced by LG-related factors and can be modulated by other proxies or treating HCPs, leading to a definitive decision. Although insights into these underlying mechanisms could facilitate the proxy decision-making process for both LGs and researchers, treating HCPs could act as an independent party.

Differential restoration of functional hyperemia by antihypertensive drug classes in hypertension-related cerebral small vessel disease

Dementia resulting from small vessel diseases (SVDs) of the brain is an emerging epidemic for which there is no treatment. Hypertension is the major risk factor for SVDs, but how hypertension damages the brain microcirculation is unclear. Here, we show that chronic hypertension in a mouse model progressively disrupts on-demand delivery of blood to metabolically active areas of the brain (functional hyperemia) through diminished activity of the capillary endothelial cell inward-rectifier potassium channel, Kir2.1. Despite similar efficacy in reducing blood pressure, amlodipine, a voltage-dependent calcium-channel blocker, prevented hypertension-related damage to functional hyperemia whereas losartan, an angiotensin II type 1 receptor blocker, did not. We attribute this drug class effect to losartan-induced aldosterone breakthrough, a phenomenon triggered by pharmacological interruption of the renin-angiotensin pathway leading to elevated plasma aldosterone levels. This hypothesis is supported by the finding that combining losartan with the aldosterone receptor antagonist eplerenone prevented the hypertension-related decline in functional hyperemia. Collectively, these data suggest Kir2.1 as a possible therapeutic target in vascular dementia and indicate that concurrent mineralocorticoid aldosterone receptor blockade may aid in protecting against late-life cognitive decline in hypertensive patients treated with angiotensin II type 1 receptor blockers.

The longitudinal association between the use of antihypertensive medications and 24-hour sleep in nursing homes: results from the randomized controlled COSMOS trial

BACKGROUND

Antihypertensive medication use and sleep problems are highly prevalent in nursing home patients. While it is hypothesized that blood pressure and antihypertensive medication use can affect sleep, this has not been investigated in depth in this population. Alongside a multicomponent intervention including a systematic medication review, we aimed to investigate the longitudinal association between antihypertensive medication use, blood pressure and day- and night-time sleep over 4 months.

METHODS

This study was based on secondary analyses from the multicomponent cluster randomized controlled COSMOS trial, in which the acronym denotes the intervention: COmmuncation, Systematic pain assessment and treatment, Medication review, Organization of activities and Safety. We included baseline and 4-month follow-up data from a subgroup of nursing home patients who wore actigraphs (n = 107). The subgroup had different levels of blood pressure, from low (< 120) to high (≥ 141). Assessments included blood pressure, antihypertensive medication use, and sleep parameters as assessed by actigraphy.

RESULTS

We found a significant reduction in total sleep time at month four in the intervention group compared to the control group. When analysing the control group alone, we found a significant association between antihypertensive medication use and increased daytime sleep. We also found negative associations between blood pressure, antihypertensive medication use and sleep onset latency in the control group.

CONCLUSIONS

Our results suggest a correlation between excessive daytime sleep and antihypertensive medication use. These findings should be followed up with further research, and with clinical caution, as antihypertensive medications are frequently used in nursing homes, and sleep problems may be especially detrimental for this population.

TRIAL REGISTRATION

The trial is registered at clinicaltrials.gov ( NCT02238652 ).

Multiple antihypertensive use and risk of mortality in residents of aged care services: a prospective cohort study

AIMS

The objective of this study is to investigate the association between multiple antihypertensive use and mortality in residents with diagnosed hypertension, and whether dementia and frailty modify this association.

METHODS

This is a two-year prospective cohort study of 239 residents with diagnosed hypertension receiving antihypertensive therapy across six residential aged care services in South Australia. Data were obtained from electronic medical records, medication charts and validated assessments. The primary outcome was all-cause mortality and the secondary outcome was cardiovascular-related hospitalizations. Inverse probability weighted Cox models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality. Covariates included age, sex, dementia severity, frailty status, Charlson's comorbidity index and cardiovascular comorbidities.

RESULTS

The study sample (mean age of 88.1 ± 6.3 years; 79% female) included 70 (29.3%) residents using one antihypertensive and 169 (70.7%) residents using multiple antihypertensives. The crude incidence rates for death were higher in residents using multiple antihypertensives compared with residents using monotherapy (251 and 173/1000 person-years, respectively). After weighting, residents who used multiple antihypertensives had a greater risk of mortality compared with monotherapy (HR 1.40, 95%CI 1.03-1.92). After stratifying by dementia diagnosis and frailty status, the risk only remained significant in residents with diagnosed dementia (HR 1.91, 95%CI 1.20-3.04) and who were most frail (HR 2.52, 95%CI 1.13-5.64). Rate of cardiovascular-related hospitalizations did not differ among residents using multiple compared to monotherapy (rate ratio 0.73, 95%CI 0.32-1.67).

CONCLUSIONS

Multiple antihypertensive use is associated with an increased risk of mortality in residents with diagnosed hypertension, particularly in residents with dementia and among those who are most frail.

The effects of stress on cardiovascular disease and Alzheimer's disease: Physical exercise as a counteract measure

AD is a complicated multi-systemic neurological disorder that involves different biological pathways. Several risk factors have been identified, including chronic stress. Chronic stress produces an alteration in the activity of the hypothalamic pituitary adrenal (HPA) system, and the autonomic nervous system (ANS), which over time increase the risk of AD and also the incidence of cardiovascular disease (CVD) and risk factors, such as hypertension, obesity and type 2 diabetes, associated with cognitive impairment and AD. Considering the multi-factorial etiology of AD, understanding the complex interrelationships between different risk factors is of potential interest for designing adequate strategies for preventing, delaying the onset or slowing down the progression of this devastating disease. Thus, in this review we will explore the general mechanisms and evidence linking stress, cardiovascular disease and AD, and discuss the potential benefits of physical activity for AD by counteracting the negative effects of chronic stress, CVD and risk factors.

Cardiovascular drug use among people with cognitive impairment living in nursing homes in northern Sweden

PURPOSE

The aim of this study was to describe changes in the pattern of cardiovascular agents used in elderly people living in nursing homes between 2007 and 2013. Further, the aim was to analyse the use of cardiovascular drugs in relation to cognitive impairment and associated factors within the same population, where prescription of loop diuretics was used as a proxy for heart failure.

METHODS

Two questionnaire surveys were performed including 2494 people in 2007 and 1654 people in 2013 living in nursing homes in northern Sweden. Data were collected concerning drug use, functioning in activities of daily living (ADL) and cognition, using the Multi-Dimensional Dementia Assessment Scale (MDDAS). The use of different drugs and drug classes among people at four different levels of cognitive function in 2007 and 2013 were compared.

RESULTS

The proportion of people prescribed ASA and diuretics was significantly lower at all four levels of cognitive function in 2013 compared to 2007. Among people prescribed loop diuretics, the use of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (ACEI/ARBs) increased from 37.8 to 45.6%, β-blockers from 36.0 to 41.8% and warfarin from 4.4 to 11.4%. The use of warfarin, ACEI/ARBs, β-blockers and mineralocorticoid receptor antagonists (MRAs) were less common among individuals with more severe cognitive impairment.

CONCLUSION

The results indicate that cardiovascular drug treatment has improved between 2007 and 2013, but there is room for further improvement, especially regarding adherence to guidelines for heart failure. Increasing cognitive impairment had an effect on treatment patterns for heart failure and atrial fibrillation.

Potentially inappropriate prescribing in dementia: a state-of-the-art review since 2007

OBJECTIVES

Dementia frequently occurs alongside comorbidities. Coexisting conditions are often managed with multiple medications, leading to increased risk of potentially inappropriate medication and adverse drug reactions. We aimed to estimate prevalence of, and identify factors reported to be associated with, potentially inappropriate prescribing (PIP) for older individuals diagnosed with dementia.

DESIGN

We used a state-of-the-art review approach, selecting papers written in English and published from 2007 to January 2018. Publications were retrieved from Scopus and Web of Science databases. Inclusion criteria included a formal diagnosis of dementia, a formal classification of PIP and reported prevalence of PIP as an outcome. Random effects models were used to provide a pooled estimate of prevalence of PIP. The Appraisal tool for Cross-Sectional Studies (AXIS tool) was used to assess bias in the included studies.

RESULTS

The bibliographic search yielded 221 citations, with 12 studies meeting the inclusion criteria. The estimates of PIP prevalence for people living with dementia ranged from 14% to 64%. Prevalence was 31% (95% CI 9 to 52) in the community, and 42% (95% CI 30 to 55) in nursing/care homes. PIP included prescribing likely related to dementia (eg, hypnotics and sedative and cholinesterase inhibitors) and prescribing related to treatment of comorbidities (eg, cardiovascular drugs and non-steroidal anti-inflammatory medication). Higher levels of comorbidity were associated with increased risk of PIP; however, only one study investigated associations with specific comorbidities of dementia.

CONCLUSION

PIP remains a significant issue in healthcare management for people living with dementia. Higher levels of comorbidity are associated with increased prevalence of PIP, but the specific conditions driving this increase remain unknown. Further work is necessary to investigate PIP related to the presence of common comorbidities in patients living with dementia.

Blood Pressure Variability and Progression of Clinical Alzheimer Disease

Blood pressure variability (BPV) has been shown to have predictive value over blood pressure (BP) levels alone in stroke patients. We assessed whether BPV predicts cognitive and functional decline in Alzheimer disease, using data from a randomized trial (NILVAD [A European Multicentre Double-blind Placebo-controlled Phase III Trial of Nilvadipine in Mild to Moderate Alzheimer’s Disease]). Patients with mild-to-moderate Alzheimer disease were included if they had ≥3 office BP measurements available to determine visit-to-visit BPV. Day-to-day BPV was assessed using home BP measurements in a subsample. The variation independent of mean was used to calculate BPV. Outcomes were change in Alzheimer’s Disease Assessment Scale–cognitive subscale-12 and Disability Assessment for Dementia after 1 and 1.5 years. A total of 460 patients aged 72.1 (SD=8.1) years, with mean BP of 134.0/75.1 (10.9/6.3) mm Hg were included. After 1 year, patients in the highest quartile of BPV had deteriorated more on Alzheimer’s Disease Assessment Scale–cognitive subscale compared with patients in the lowest quartile (systolic: β, 2.24 [95% CI, 0.11–4.38], P =0.040; diastolic: β, 2.54 [95% CI, 0.33–4.75] P =0.024). This association was still present after 1.5 years (systolic: β, 2.86 [95% CI, 0.35–5.36], P =0.026; diastolic: β, 3.30 [95% CI, 0.67–5.93], P =0.014). There was no effect of visit-to-visit BPV on Disability Assessment for Dementia. Day-to-day BPV was available for 46 patients. Significant associations were observed between day-to-day BPV and deterioration on Alzheimer’s Disease Assessment Scale–cognitive subscale (systolic: P =0.036) and Disability Assessment for Dementia (systolic: P =0.020; diastolic: P =0.007) after 1 year, but not after 1.5 years. All associations were adjusted for potential confounders, including intervention group. In conclusion, this post hoc analysis indicates that higher visit-to-visit and day-to-day BPV might be associated with progression of Alzheimer disease. Targeting BPV may be a future target to slow decline in patients with Alzheimer disease.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov . Unique identifier: NCT02017340.

Diagnostic accuracy of office blood pressure compared to home blood pressure in patients with mild cognitive impairment and dementia

Background:

Hypertension and cognitive impairment often coexist in older people. Office blood pressure measurement is a poor indicator for diagnosing hypertension in the general population. However, its diagnostic accuracy has not been substantially studied in patients with cognitive impairment.

Aim:

The aim of this study was to determine the proportion of misdiagnosis of hypertension in patients with mild cognitive impairment and dementia compared to no cognitive impairment, by comparing office blood pressure measurement with home blood pressure measurement.

Methods:

A cross-sectional study including consecutive patients visiting a memory clinic between 2014 and 2017. Home blood pressure was measured for one week according to the European guidelines. Office blood pressure was assessed during routine clinical practice. Using guideline definitions for normal blood pressure and hypertension, we investigated the proportion of disagreement between office blood pressure measurement and home blood pressure measurement. Univariable and multivariable logistic regression compared disagreement in diagnosis between patients with dementia, mild cognitive impairment and no cognitive impairment.

Results:

Of 213 patients (aged 73.4±9.0 years, 42% women) 82 had dementia, 65 had mild cognitive impairment and 66 had no cognitive impairment. Mean office blood pressure was 156/84±23/11 mmHg and mean home blood pressure was 139/79±16/10 mmHg. In 31% of patients, there was disagreement in hypertension diagnosis. This proportion was higher for mild cognitive impairment (38.5%) and dementia (35.4%) compared to no cognitive impairment (18.2%), with adjusted odds ratios of 3.7 (95% confidence interval 1.5–9.0), P=0.005 for mild cognitive impairment and 3.4 (1.3–8.6), P=0.011 for dementia.

Conclusions:

In memory clinic patients with dementia and mild cognitive impairment, the diagnostic accuracy of office blood pressure measurement is lower compared to patients without cognitive impairment. To avoid the risk of making improper treatment decisions in this vulnerable group, a diagnosis of hypertension should be based on home blood pressure measurement, not office blood pressure measurement.

Blood Pressure Lowering With Nilvadipine in Patients With Mild-to-Moderate Alzheimer Disease Does Not Increase the Prevalence of Orthostatic Hypotension

Background Hypertension is common among patients with Alzheimer disease. Because this group has been excluded from hypertension trials, evidence regarding safety of treatment is lacking. This secondary analysis of a randomized controlled trial assessed whether antihypertensive treatment increases the prevalence of orthostatic hypotension (OH) in patients with Alzheimer disease. Methods and Results Four hundred seventy-seven patients with mild-to-moderate Alzheimer disease were randomized to the calcium-channel blocker nilvadipine 8 mg/day or placebo for 78 weeks. Presence of OH (blood pressure drop ≥20/≥10 mm Hg after 1 minute of standing) and OH-related adverse events (dizziness, syncope, falls, and fractures) was determined at 7 follow-up visits. Mean age of the study population was 72.2±8.2 years and mean Mini-Mental State Examination score was 20.4±3.8. Baseline blood pressure was 137.8±14.0/77.0±8.6 mm Hg. Grade I hypertension was present in 53.4% (n=255). After 13 weeks, blood pressure had fallen by -7.8/-3.9 mm Hg for nilvadipine and by -0.4/-0.8 mm Hg for placebo ( P<0.001). Across the 78-week intervention period, there was no difference between groups in the proportion of patients with OH at a study visit (odds ratio [95% CI]=1.1 [0.8-1.5], P=0.62), nor in the proportion of visits where a patient met criteria for OH, corrected for number of visits (7.7±13.8% versus 7.3±11.6%). OH-related adverse events were not more often reported in the intervention group compared with placebo. Results were similar for those with baseline hypertension. Conclusions This study suggests that initiation of a low dose of antihypertensive treatment does not significantly increase the risk of OH in patients with mild-to-moderate Alzheimer disease. Clinical Trial Registration URL: https://www.clinicaltrials.gov . Unique identifier: NCT02017340.

Dynamic Regulation of Cerebral Blood Flow in Patients With Alzheimer Disease

Cerebral autoregulation and baroreflex sensitivity are key mechanisms that maintain cerebral blood flow. This study assessed whether these control mechanisms are affected in patients with dementia and mild cognitive impairment due to Alzheimer disease, as this would increase the risks of antihypertensive treatment. We studied 53 patients with dementia (73.1 years [95% confidence interval (CI), 71.4–74.8]), 37 patients with mild cognitive impairment (69.2 years [95% CI, 66.4–72.0]), and 47 controls (69.4 years [95% CI, 68.3–70.5]). Beat-to-beat blood pressure (photoplethysmography), heart rate, and cerebral blood flow velocity (transcranial Doppler) were measured during 5-minute rest (sitting) and 5 minutes of orthostatic challenges, using repeated sit-to-stand maneuvers. Cerebral autoregulation was assessed using transfer function analysis and the autoregulatory index. Baroreflex sensitivity was estimated with transfer function analysis and by calculating the heart rate response to blood pressure changes during the orthostatic challenges. Dementia patients had the lowest cerebral blood flow velocity ( P =0.004). During rest, neither transfer function analysis nor the autoregulatory index indicated impairments in cerebral autoregulation. During the orthostatic challenges, higher autoregulatory index ( P =0.011) and lower transfer function gain ( P =0.017), indicating better cerebral autoregulation, were found in dementia (4.56 arb. unit [95% CI, 4.14–4.97]; 0.59 cm/s per mm Hg [95% CI, 0.51–0.66]) and mild cognitive impairment (4.59 arb. unit [95% CI, 4.04–5.13]; 0.51 cm/s per mm Hg [95% CI, 0.44–0.59]) compared with controls (3.71 arb. unit [95% CI, 3.35–4.07]; 0.67 cm/s per mm Hg [95% CI, 0.59–0.74]). Baroreflex sensitivity measures did not differ between groups. In conclusion, the key mechanisms to control blood pressure and cerebral blood flow are not reduced in 2 stages of Alzheimer disease compared with controls, both in rest and during orthostatic changes that reflect daily life challenges.

Withdrawal of antihypertensive therapy in people with dementia: feasibility study

BACKGROUND

This study explored the feasibility of a randomised controlled withdrawal trial of antihypertensive medication in normotensive people with dementia. Feasibility aspects included response, recruitment, exclusion and drop-out rates, suitability of outcome measures, acceptability of study procedures and an indicative economic evaluation for a randomised controlled trial.

METHODS

A cohort study attempting the withdrawal of antihypertensive drugs where appropriate and a feasibility study of home-based blood pressure monitoring, in people with dementia treated for hypertension, was undertaken. Interviews with participants and carers and an indicative economic evaluation were also undertaken.

RESULTS

Three hundred and sixty-two primary care practices in the East Midlands were contacted of which only 41 (11% (95%CI 8-15%)) agreed to support the study. These 41 practices posted 940 letters to potential participants. Thirty participants were enrolled in the cohort study of whom 9 were eligible for the antihypertensive withdrawal programme, 20 participated in a home blood pressure monitoring sub-group analysis and 12 took part in an interview study. Twenty-two of those enrolled in the cohort study were followed up at 6 months. The withdrawal programme was acceptable to participants and general practitioners (GPs). The study procedures including assessments and home blood pressure monitoring were acceptable to the participants and their carers. The economic evaluation was not possible.

CONCLUSION

A withdrawal trial of antihypertensive medication in normotensive people with dementia may not be feasible in the UK because of low recruitment rates.

Blood Pressure and All-Cause Mortality by Level of Cognitive Function in the Elderly: Results From a Population-Based Study in Rural Greece

This study aimed to investigate whether the effect of blood pressure (BP) on mortality differs by levels of cognitive function. The associations of brachial systolic BP, diastolic BP, mean arterial pressure (MAP), and pulse pressure with all-cause mortality were prospectively explored (follow-up 7.0±2.2 years) in 660 community-dwelling individuals (≥60 years) using adjusted Cox models, stratified by cognitive impairment (Mini-Mental State Examination [MMSE] <24). No association between brachial BP variables and mortality was shown for the total sample in quartiles analysis; however, MAP in the highest quartile, compared with the second, was associated with mortality (hazard ratio, 1.85; 95% confidence intervals, 1.09-3.12) among cognitively impaired individuals. The fractional-polynomials approach for BP confirmed this finding and further showed, solely in the MMSE <24 subcohort, U-shaped trends of MAP and systolic BP, with increased mortality risk in extremely low or high values; no such pattern was evident for patients with MMSE ≥24. Elderly individuals with cognitive impairment might be more susceptible to the detrimental effects of low and elevated MAP and systolic BP.

The association between SBP and mortality risk differs with level of cognitive function in very old individuals

Objective:

Cognitive impairment and dementia are highly prevalent in very old populations. Cardiovascular disease is a common cause of death in people with dementia.

This study investigated whether the association of blood pressure (BP) with mortality differed with respect to mini-mental state examination (MMSE) score in a representative sample of very old individuals.

Methods:

The sample consisted of 1115 participants aged 85, 90, and at least 95 years from the Umeå85+/GErontological Regional DAtabase cohort study. The main outcome was all-cause mortality within 2 years according to BP and MMSE score, using Cox proportional-hazard regression models adjusted for sociodemographic and clinical characteristics associated with death.

Results:

Mean age, MMSE score, and SBP and DBP were 89.4 ± 4.6 years, 21.1 ± 7.6, 146.1 ± 23.4 mmHg, and 74.1 ± 11.7 mmHg, respectively. Within 2 years, 293 (26%) participants died. BP was not associated independently with mortality risk, except among participants with MMSE scores of 0–10 among whom mortality risk was increased in association with SBP at least 165 mmHg and 125 mmHg or less, compared with 126–139 mmHg (adjusted hazard ratio 4.54, 95% confidence interval = 1.52–13.60 and hazard ratio 2.23, 95% confidence interval = 1.12–4.45, respectively). In age and sex-adjusted analyses, SBP 125 mmHg or less was associated with increased mortality risk in participants with MMSE scores at least 18.

Conclusion:

In people aged at least 85 years, the association of SBP with mortality appears to differ with respect to MMSE score. Very old individuals with very severe cognitive impairment and low or high BP may have increased mortality risk.