Cardiovascular drug therapy in the elderly: theoretical and practical considerations

Repurposing effect of cardiovascular-metabolic drug to increase lifespan: a systematic review of animal studies and current clinical trial progress

With the increase in life expectancy, aging has emerged as a significant health concern. Due to its various mechanisms of action, cardiometabolic drugs are often repurposed for other indications, including aging. This systematic review analyzed and highlighted the repositioning potential of cardiometabolic drugs to increase lifespan as an aging parameter in animal studies and supplemented by information from current clinical trial registries. Systematic searching in animal studies was performed based on PICO: "animal," "cardiometabolic drug," and "lifespan." All clinical trial registries were also searched from the WHO International Clinical Trial Registry Platform (ICTRP). Analysis of 49 animal trials and 10 clinical trial registries show that various cardiovascular and metabolic drugs have the potential to target lifespan. Metformin, acarbose, and aspirin are the three most studied drugs in animal trials. Aspirin and acarbose are the promising ones, whereas metformin exhibits various results. In clinical trial registries, metformin, omega-3 fatty acid, acarbose, and atorvastatin are currently cardiometabolic drugs that are repurposed to target aging. Published clinical trial results show great potential for omega-3 and metformin in healthspan. Systematic Review Registration: crd.york.ac.uk/prospero/display_record.php?RecordID=457358, identifier: CRD42023457358.

Association between statin use and physical performance in home-dwelling older patients receiving polypharmacy: cross-sectional study

Background

In older patients with polypharmacy and multiple comorbidities, even low grades of statin-associated muscle symptoms may have clinical implications. The aim of this study was therefore to investigate the potential associations between statin use and measures of physical performance and muscle function.

Methods

Participants were aged 70+, treated with at least seven regular systemic medications, and not expected to die or become institutionalized within 6 months. Physical performance measured as gait speed and Short Physical Performance Battery (SPPB) score, and muscle function measured as grip strength, were compared between users and non-users of statins. In the subgroup of statin users, the dose-response relationship was assessed using harmonized simvastatin equivalents adjusted for statin potency, pharmacokinetic interactions and SLCO1B1 c.521 T > C genotype. Multiple linear regression analyses were applied to investigate potential associations between stain use and exposure as independent variables, and physical performance and muscle function as outcomes, adjusted for age, gender, body mass, comorbidity, disability and dementia.

Results

174 patients (87 users and 87 non-users of statins) with a mean (SD) age of 83.3 (7.3) years were included. In analyses adjusted only for gender, grip strength was significantly higher in users than in non-users of statins [regression coefficient (B) 2.7, 95% confidence interval (CI) 1.0 to 4.4]. When adjusted for confounders, the association was no longer statistically significant (B 1.1, 95% CI − 0.5 to 2.7). SPPB and gait speed was also better in statin users than in non-users, but the differences were not statistically significant. In dose-response analyses adjusted for confounders, we found a statistically significant increase in SPPB score (B 0.01, 95% CI 0.00 to 0.02) and gait speed (B 0.001, 95% CI 0.000 to 0.002) per mg increase in simvastatin equivalents.

Conclusions

In contrast to our hypothesis, statin use and exposure was associated with better measures of physical performance and muscle function in older patients with complex drug treatment. The unexpected findings of this cross-sectional, observational study should be further investigated by comparing physical performance before and after statin initiation or statin withdrawal in prospective studies.

Trial registration

ClinicalTrials.gov identifier: NCT02379455, registered March 5, 2015.

Pharmacologic management of chronic stable angina

Chronic stable angina is a significant problem in older adults. The goal of therapy is to provide symptomatic relief, improve patient quality of life, and prevent subsequent angina or myocardial infarction that could lead to sudden death. The efficacy and safety of drugs such as beta-blockers and calcium channel blockers for managing chronic stable angina in older adults has not been rigorously investigated. Drug selection should be based on physiologic alterations, patient comorbidities, adverse reaction profile, and cost.

Atrial fibrillation and heart failure in the elderly

Atrial fibrillation (AF) is a common clinical problem in elderly patients and especially in those with heart failure (HF). It is a major risk factor for serious cardiovascular events, such as stroke, HF and premature death. Both the prevalence and incidence of AF increase with age and its prevalence in the United States are estimated at more than 2.2 million, with nearly 75% of patients aged >65 years. Aging-related atrial remodeling with fibrosis, dilation and mitochondrial DNA mutations predispose elderly patients to AF. Current management options for AF, including rate control and anticoagulation therapy, can be successfully applied to the elderly population. New antiarrhythmic and anticoagulation medications such as dronedarone and dabigatran, respectively, can impact the approach to therapy in the elderly. Non-pharmacological options such as catheter-based ablation have also gained prominence and have been incorporated into the guidelines for management of AF. However, more trials in the elderly and very elderly segments are needed to clarify the safety and long-term efficacy of the new treatment options.

Use of antiarrhythmic drugs in elderly patients

Human aging is a global issue with important implications for current and future incidence and prevalence of health conditions and disability. Cardiac arrhythmias, including atrial fibrillation, sudden cardiac death, and bradycardia requiring pacemaker placement, all increase exponentially after the age of 60. It is important to distinguish between the normal, physiological consequences of aging on cardiac electrophysiology and the abnormal, pathological alterations. The age-related cardiac changes include ventricular hypertrophy, senile amyloidosis, cardiac valvular degenerative changes and annular calcification, fibrous infiltration of the conduction system, and loss of natural pacemaker cells and these changes could have a profound effect on the development of arrhythmias. The age-related cardiac electrophysiological changes include up- and down-regulation of specific ion channel expression and intracellular Ca(2+) overload which promote the development of cardiac arrhythmias. As ion channels are the substrates of antiarrhythmic drugs, it follows that the pharmacokinetics and pharmacodynamics of these drugs will also change with age. Aging alters the absorption, distribution, metabolism, and elimination of antiarrhythmic drugs, so liver and kidney function must be monitored to avoid potential adverse drug effects, and antiarrhythmic dosing may need to be adjusted for age. Elderly patients are also more susceptible to the side effects of many antiarrhythmics, including bradycardia, orthostatic hypotension, urinary retention, and falls. Moreover, the choice of antiarrhythmic drugs in the elderly patient is frequently complicated by the presence of co-morbid conditions and by polypharmacy, and the astute physician must pay careful attention to potential drug-drug interactions. Finally, it is important to remember that the use of antiarrhythmic drugs in elderly patients must be individualized and tailored to each patient's physiology, disease processes, and medication regimen.

Registered nurses' medication management of the elderly in aged care facilities

BACKGROUND

Data on adverse drug reactions (ADRs) showed a rising trend in the elderly over 65 years using multiple medications.

AIM

To identify registered nurses' (RNs) knowledge of medication management and ADRs in the elderly in aged care facilities; evaluate an education programme to increase pharmacology knowledge and prevent ADRs in the elderly; and develop a learning programme with a view to extending provision, if successful.

METHOD

This exploratory study used a non-randomized pre- and post-test one group quasi-experimental design without comparators. It comprised a 23-item knowledge-based test questionnaire, one-hour teaching session and a self-directed learning package. The volunteer sample was RNs from residential aged care facilities, involved in medication management. Participants sat a pre-test immediately before the education, and post-test 4 weeks later (same questionnaire). Participants' perceptions obtained.

FINDINGS

Pre-test sample n = 58, post-test n = 40, attrition rate of 31%. Using Microsoft Excel 2000, descriptive statistical data analysis of overall pre- and post-test incorrect responses showed: pre-test proportion of incorrect responses = 0.40; post-test proportion of incorrect responses = 0.27; Z-test comparing pre- and post-tests scores of incorrect responses = 6.55 and one-sided P-value = 2.8E-11 (P < 0.001).

CONCLUSION AND IMPLICATIONS

Pre-test showed knowledge deficits in medication management and ADRs in the elderly; post-test showed statistically significant improvement in RNs' knowledge. It highlighted a need for continuing professional education. Further studies are required on a larger sample of RNs in other aged care facilities, and on the clinical impact of education by investigating nursing practice and elderly residents' outcomes.

Perioperative use of beta-blockers in the elderly patient

Elderly patients are increasingly referred for complex surgery, but are at particular risk for coronary artery disease. One strategy to prevent perioperative cardiac events in elderly patients is to employ perioperative beta-blockade, but doing so has the potential to increase the incidence of congestive heart failure, perioperative hypotension, bradycardia, and stroke. This article examines common comorbidities in the elderly who may benefit from the chronic use of beta-blockers, prophylactic perioperative use of beta-blockers including timing, dosage, and choice of beta-blocker, the pharmacologic effects of aging, and recommendations on the use of beta-blockers.

Use of beta-adrenoceptor antagonists in older patients with chronic obstructive pulmonary disease and cardiovascular co-morbidity: safety issues

The incidence of and mortality from both chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD) increase with age. In addition, the average age of patients with COPD and CVD is also increasing as a result of improvements in both pharmacological and non-pharmacological treatments. Coronary artery disease is a compelling indication for beta-adrenoceptor antagonist use in a population in whom beta-adrenoceptor antagonism is often viewed as contraindicated. beta-Adrenoceptor antagonists have been proven to improve cardiovascular morbidity and mortality but have been under-utilized in patients with COPD with concomitant CVD because of a fear of bronchoconstriction and adverse effects, particularly in the elderly. The advanced age of patients with COPD and CVD, along with the sheer number of patients with these diseases, necessitates that clinicians understand the treatment of these co-morbidities using seemingly conflicting therapy in the form of beta-adrenoceptor agonists and antagonists. We review changes in the pharmacokinetics and pharmacodynamics of beta-adrenoceptor antagonists in the elderly, the role of beta-adrenoceptor antagonists in CVD and the literature regarding the safety and mortality benefits of beta-adrenoceptor antagonists in elderly patients with COPD and concomitant CVD. We conclude that cardioselective beta-adrenoceptor antagonists appear to be safe to use in elderly male patients with mild-to-moderate COPD who have a compelling indication for beta-adrenoceptor antagonist therapy. Data in female patients are very limited. Nonselective beta-adrenoceptor antagonists should be avoided in general, except in patients with heart failure who might benefit significantly from the use of carvedilol. beta-Adrenoceptor antagonists have been shown to improve mortality in older patients with coexisting CVD and COPD.

Pharmacodynamics in older adults: a review

BACKGROUND

Older individuals experience physiologic changes in organ function related to aging or to specific disease processes. These changes can affect drug pharmacodynamics in older adults.

OBJECTIVE

The goal of this article was to review age-related changes in pharmacodynamics and their clinical relevance.

METHODS

PubMed and International Pharmaceutical Abstracts were searched (January 1980-June 2006) for the following combination of terms: pharmacodynamic and elderly, geriatric or aged. References cited in other reviews were also evaluated. The current review focused on age-related pharmacodynamic changes in agents affecting the central nervous system (CNS), cardiovascular, and endocrine functions.

RESULTS

Older adults frequently demonstrate an exaggerated response to CNS-active drugs. This is in part due to an underlying age-related decline in CNS function and in part due to increased pharmacodynamic sensitivity for some benzodiazepines, anesthetics, and opioids. The most important pharmacodynamic differences with age for cardiovascular agents are the decrease in effect for beta-adrenergic agents. This decline in response in vascular, cardiac, and pulmonary tissue may be due to a decrease in Gs protein interactions. Most studies indicate there is no decrease in cx-receptor sensitivity with age. Angiotensin-converting enzyme inhibitors do not show age-related differences in elderly patients. With the dihydropyridine calcium channel blockers, there was a slight increase in effect for older adults, but this was only for treatment-naive patients and was transient. Nondihydropyridines did not show an age- associated change in pharmacodynamic effect; however, in the elderly, there appeared to be a decrease in the PR interval prolongation normally seen with these agents. Studies of diuretics indicated that the changes in diuretic and natriuretic effects seen in the elderly were associated with pharmacokinetic changes and were not pharmacodynamic in nature. There was a lack of consistent evidence regarding whether sulfonylureas show age-related changes in pharmacodynamic effect.

CONCLUSIONS

There is a general trend of greater pharmacodynamic sensitivity in the elderly; however, this is not universal, and these age-related changes must be investigated agent-by-agent until further research yields greater understanding of the molecular mechanisms underlying the aging process.

Effects of long-term angiotensin converting enzyme inhibition on cardiovascular variability in aging rats

We studied the effects of chronic (4 weeks) angiotensin converting enzyme inhibition with captopril on arterial pressure (AP) and heart rate (HR) variability, as well as on cardiac baroreflex sensitivity (BRS), in aged (20 months) rats. Series of basal RR interval (RRi) and systolic AP (SAP) were studied by autoregressive spectral analysis with oscillations quantified in low (LF: 0.2-0.8 Hz) and high frequency (HF: 0.8-2.5 Hz). BRS was measured by linear regression between HR and MAP changes. Captopril did not affect the spectra of RRi or SAP in young rats. Aged rats presented a reduction in variance (time domain) and in LF and HF oscillations of RRi and SAP. Captopril induced, in aged rats, a decrease in absolute and normalized LF oscillations and in LF/HF ratio of RRi. Captopril also reduced the variance, without changing its LF or HF components of SAP. Reflex tachycardia was reduced in aged as compared to young rats (-1.1+/-0.2 versus -3.4+/-0.5 bpm/mm Hg) and captopril did not affect it. Reflex bradycardia was also reduced in aged rats (-0.7+/-0.5 versus -2.0+/-0.4 bpm/mm Hg), but captopril prevented this attenuation in aged rats (-2.3+/-0.3 versus -0.7+/-0.5 bpm/mm Hg). These data indicate that there is a reduction in HR and SAP variability during aging, suggesting impairment of cardiovascular autonomic control. Captopril was able to change the power of oscillatory components of RRi, suggesting a shift in cardiac sympatho/vagal balance toward parasympathetic predominance. In addition, blockage of ACE improved the reflex bradycardia, but not the reflex tachycardia in aged rats.

Medication use and prescribing considerations for elderly patients

Older adults consume more medications than any other segment of the population. Increasing lifespan means that more people will live into old age, frequently with disabilities and conditions man-aged by medications. Age-associated physiologic changes, medication use patterns, and adverse drug effects and interactions place the older adult at high risk for medication-related problems. Older adults living in institutions, those with complex medical problems,and those who do not adhere to medication regimens are at highest risk for negative health outcomes from medication mishaps. Dentists must be able to identify older adults who are susceptible to adverse drug events and to recognize which medications are most likely to precipitate problems.

Hypertension in the Elderly

Elderly individuals with hypertension show specific characteristics as a result of advancing arteriosclerosis, a high frequency of isolated systolic hypertension, increased pulse pressure and orthostatic hypotension. The necessity to treat hypertension in the elderly, including isolated systolic hypertension, has been demonstrated in many large-scale intervention trials. Young-old (65-74 years of age) hypertensive patients should be treated the same as nonelderly hypertensive patients. In old-old (75-84 years of age) patients with mild hypertension (140-159/90-99 mm Hg), the recommended target blood pressure (BP) is <140/90 mm Hg. In old-old (75-84 years of age) and oldest-old (> or =85 years of age) patients with systolic BP > or =160 mm Hg, cautious treatment is required. An intermediate target BP of <150 mm Hg is appropriate, followed by a final target BP of <140 mm Hg, if tolerated. Nonmedical therapy, such as salt restriction, exercise and weight reduction, is useful in the elderly. However, individualised management of nonmedical therapy is necessary to avoid deterioration of quality of life resulting from strict management of the patient's lifestyle. Diuretics, calcium channel antagonists, ACE inhibitors and angiotensin II type 1 receptor antagonists have been established as first-line antihypertensive drugs in the elderly. Use of combination therapy helps to achieve target BPs. The starting dose of each drug should be half the usual dose for nonelderly patients, and may be increased at intervals of >4 weeks, with achievement of the target BP in 3-6 months or longer. In hypertensive patients with co-morbid diseases, the target BP should be determined individually and antihypertensive drugs selected bearing in mind the patient's clinical circumstances. Avoiding hypoperfusion of target organs is very important in elderly hypertensive patients. When treating hypertension in elderly patients, the approach should be to identify individual pathophysiological characteristics and lower the BP cautiously and slowly.

Angiotensin-Converting Enzyme Inhibitor Use in Elderly Patients Hospitalized with Heart Failure and Left Ventricular Systolic Dysfunction

PURPOSE

Although angiotensin-converting enzyme (ACE) inhibitors are recommended for all patients with systolic heart failure, prior studies suggest that elderly cohorts are less likely to receive such therapy. The purpose of this study was to determine the age dependence of adherence to guideline-based medical care in hospitalized heart failure patients.

METHODS

We performed a multicenter observational cohort study including 613 patients admitted to participating hospitals with a primary diagnosis of heart failure with ejection fraction < or =40%. This cohort was divided into four age groups (group 1: <60, group 2: 60-69, group 3: 70-79, and group 4: 80 years) and adherence to guideline-based medical care was measured.

RESULTS

ACE inhibitors were administered to 83% of ideal heart failure patients, and this rate was similar for all age groups. Elderly patients received significantly lower ACE inhibitor dosages compared to their younger counterparts (168, 148, 125 and 117 mg captopril in groups 1, 2, 3, and 4, respectively, p=0.001). Lower creatinine clearance (p<0.001), prior residence in a long-term care facility (p=0.037), intolerance to ACE inhibitors (p=0.006), lower blood pressure (p=0.005), absence of a history of hypertension (p=0.005), and no prior heart failure hospitalizations within the past year (p=0.001) were found to be independent predictors of low ACE inhibitor dosing.

CONCLUSIONS

In this heart failure benchmarking project, elderly patients received guideline-based ACE inhibitor therapy at similar rates, but at lower doses, compared to their younger counterparts.

Clinical Pharmacology

The dose of a drug is a major determinant of its safety, and establishing a safe dose of a novel drug is a prime objective during clinical development. The design of pre-marketing clinical trials precludes the representation of important subpopulations such as children, the elderly and people with co-morbidities. Therefore, postmarketing surveillance (PMS) activities are required to monitor the safety profile of drugs in real clinical practice. Furthermore, individual variations in pharmacogenetic profiles, the immune system, drug metabolic pathways and drug-drug interactions are also important factors in the occurrence of adverse drug reactions. Thus, the safety of a drug is a major clinical consideration before and after it is marketed. A multidisciplinary approach is required to enhance the safety profile of drugs at all stages of development, including PMS activities. Clinical pharmacology encompasses a range of disciplines and forms the backbone of drug safety consideration during clinical drug development. In this review we give an overview of the clinical drug development process and consider its limitations. We present a discussion of several aspects of clinical pharmacology and their application to enhancing drug safety. Pharmacokinetic-pharmacodynamic modelling provides a method of predicting a clinically safe dose; consideration of drug pharmacokinetics in special populations may enhance safe therapeutics in a wider spectrum of patients, while pharmacogenetics provides the possibility of genotype-specific therapeutics. Pharmacovigilance activities are also discussed. Given the complex nature and unpredictability of type B reactions, PMS activities are crucial in managing the risks drugs pose to the general population. The various aspects of clinical pharmacology discussed make a strong case for this field as the backbone of optimising and promoting safe development and use of drugs.