Older Adults in Clinical Research and Drug Development

On the perspective of an aging population and its potential impact on drug attrition and pre-clinical cardiovascular safety assessment

There is no refuting that America's population is growing older: for the first time in US history, by 2034 older adults (defined as >65 years of age) are projected to outnumber children under the age of 18, representing approximately 70 million people or almost 25% of the population (Lloyd-Jones et al., 2010). Described as the "silver tsunami", this flood of older adults is driven by the baby boomers (people born after World War II, from 1946 to 1964): they are now reaching old age, living longer due to significant advances in healthcare coupled with a record low birth rate, resulting in a skewed elderly population demographic. Unfortunately, older adults are also becoming increasingly unhealthy. Many often suffer from several chronic disorders requiring the use of multiple medications at a level higher than any other age group, resulting in an increased risk of drug-drug interactions (DDIs) and adverse drug reactions (ADRs). Indeed, because of age-related changes in pharmacokinetics (PK) and pharmacodynamics (PD), older adults are also more vulnerable to drug toxicity. Prescribed drugs certainly improve a range of health outcomes, but also often cause considerable ADRs, leading to devastating consequences for patients, clinicians, and manufacturers. Therefore, safe and effective pharmacotherapy remains one of the greatest growing challenges in geriatric medicine. In this review we examine the effects of aging and its impact on the increased risk of experiencing ADRs, resulting in devastating consequences for patients and manufacturers. We assess the current regulatory considerations related to the development of drugs for this population and highlight issues, concerns, and propose alternatives to the standard battery of tests focused on assessing cardiovascular (CV) safety in an attempt to develop safer and efficient new drugs for the growing elderly demographic.

Research engagement and experiences of patients pre- and post-implant of a left ventricular assist device from the mechanical circulatory support measures of adjustment and quality of life (MCS A-QOL) study

PURPOSE

Adults living with mechanical circulatory support (MCS) present with unique challenges (e.g., left ventricular assist device [LVAD]-related self-care, adverse events) to research study enrollment, engagement, and completion. The purpose of this study was to understand the experiences of adults with MCS who were eligible for and enrolled in a study of health-related quality of life (HRQOL).

METHODS

In a secondary analysis of data from the Mechanical Circulatory Support: Measures of Adjustment and Quality of Life study, we used a mixed-methods approach to evaluate research engagement and experiences among adults preparing to undergo or currently living with MCS implant. First, we assessed the cascade of study engagement. Second, we assessed research experiences using a structured interview developed for this study.

RESULTS

Of 1011 participants approached for the study, 86.7% enrolled, 12.7% declined, and 0.6% were ineligible. Of 877 participants enrolled, 272 were pre-implant (of whom 88% completed assessments; "respondents") and 605 were post-implant (of whom 74% completed assessments). Only 14% of respondents reported difficulty completing the questionnaires, 54% had previously used an iPad to complete questionnaires, and 62% reported that their experience was "as expected." Respondents qualitatively described both positive (e.g., value of research) and negative (e.g., too much time) research experiences, difficulties completing questionnaires (e.g., online platform, health literacy issues), and provided recommendations for the questionnaires and delivery.

CONCLUSIONS

Participants enjoyed participating in HRQOL research focused on MCS and had unique perspectives for improving the questionnaires. It is important to minimize the burden of participation and critical to be flexible to meet participant preferences for research engagement.

TRIAL REGISTRATION

NCT03044535 (accessible at https://clinicaltrials.gov/ct2/show/NCT03044535 ), registered February 7, 2017.

Roadmap to 2030 for Drug Evaluation in Older Adults

Changes that accompany older age can alter the pharmacokinetics (PK), pharmacodynamics (PD), and likelihood of adverse effects (AEs) of a drug. However, older adults, especially the oldest or those with multiple chronic health conditions, polypharmacy, or frailty, are often under-represented in clinical trials of new drugs. Deficits in the current conduct of clinical evaluation of drugs for older adults and potential steps to fill those knowledge gaps are presented in this communication. The most important step is to increase clinical trial enrollment of older adults who are representative of the target treatment population. Unnecessary eligibility criteria should be eliminated. Physical and financial barriers to participation should be removed. Incentives could be created for inclusion of older adults. Enrollment goals should be established based on intended treatment indications, prevalence of the condition, and feasibility. Relevant clinical pharmacology data need to be obtained early enough to guide dosing and reduce risk for participation of older adults. Relevant PK and PD data as well as patient-centered outcomes should be measured during trials. Trial data should be analyzed for differences in PK, PD, effectiveness, and safety arising from differences in age or from the presence of conditions common in older adults. Postmarket evaluations with real-world evidence and drug labeling updates throughout the product lifecycle reflecting new knowledge are also needed. A comprehensive plan is needed to ensure adequate evaluation of the safety and effectiveness of drugs in older adults.

Ventilatory defects and treatable traits in very elderly patients

Though the approach used to classify chronic respiratory diseases is changing to a treatable-traits (TT) approach, data regarding very elderly patients is lacking. The objectives of this study were to assess TT frequency in very elderly patients and to study the link between extrapulmonary TT and ventilatory defects. Individuals (≥75 years) residing in elderly care centres answered a standardised questionnaire, underwent spirometry, atopy and fractional exhaled nitric oxide assessments and had their blood pressure and peripheral pulse oximetry measured. Pulmonary, extrapulmonary and behavioural TT were evaluated. Outcome variables were an airflow limitation (post-bronchodilator z-score FEV1/FVC<-1.64) and a restrictive spirometry pattern (z-score FEV1/FVC ≥ +1.64 and z-score FVC<-1.64). Seventy-two percent of the individuals who took part in the study (n = 234) were women, and the median age of participants was 86 (IQR: 7.4). At least one pulmonary TT was identified in 105 (44.9%) individuals. The most frequent extrapulmonary TTs were: persistent systemic inflammation (47.0%), anaemia (34.4%), depression (32.5%) and obesity (27.4). Airflow limitation was exclusively associated with smoking (OR 5.03; 95% CI 1.56-16.22). A restrictive spirometry pattern was associated with cognitive impairment (OR: 3.89; 95% CI: 1.55-9.79). A high frequency of various TTs was found. The novel association between a restrictive spirometry pattern and cognitive impairment highlights the urgency of clinical research on this vulnerable age group.

Representation of women, older patients, ethnic, and racial minorities in trials of atrial fibrillation

BACKGROUND

Representation trends of women, older adults, and ethnic/racial minorities in randomized controlled trials (RCTs) of atrial fibrillation (AF) are uncertain.

METHODS

We systematically reviewed 134 AF related RCTs (phase II and III) encompassing 149,162 participants using Medline and ClinicalTrials.gov through April 2019 to determine representation trends of women, older patients (≥75 years), and ethnic/racial minorities. Weighted data on the prevalence of AF from epidemiological studies were used to compare the representation of the studied groups of interest in AF RCTs to their expected burden of the disease.

RESULTS

Only 18.7% of the RCTs reported proportion of older patients, and 12.7% RCTs reported ethnic/racial minorities. The proportions of women in RCTs versus general population were 35.2% and 35.1%, of Hispanics were 11.9% and 5.2%, of Blacks were 1.2% and 5.7%, of American Indian/Alaskans were 0.2% and 0.2%, of Asians were 14.2% and 2.4%, of native Hawaiian/Pacific Islanders were 0.05% and 0.1% and of non-Whites were 19.5% and 22.5%, respectively. The weighted mean age (SD) across the trials was 65.3 (3.2) years which was less than the corresponding weighted mean age of 71.1 (4.5) years in the comparative epidemiological data.

CONCLUSION

The reporting of older patients and ethnic/racial minorities was poor in RCTs of AF. The representation of women and American Indian/Alaskan natives matched their expected population share of disease burden. Hispanics and Asians were over-represented and Blacks, native Hawaiian/Pacific Islanders and non-Whites were under-represented in RCTs of AF.

Physician Perspectives on Deprescribing Cardiovascular Medications for Older Adults

BACKGROUND/OBJECTIVES

Guideline-based management of cardiovascular disease often involves prescribing multiple medications, which contributes to polypharmacy and risk for adverse drug events in older adults. Deprescribing is a potential strategy to mitigate these risks. We sought to characterize and compare clinician perspectives regarding deprescribing cardiovascular medications across three specialties.

DESIGN

National cross-sectional survey.

SETTING

Ambulatory.

PARTICIPANTS

Random sample of geriatricians, general internists, and cardiologists from the American College of Physicians.

MEASUREMENTS

Electronic survey assessing clinical practice of deprescribing cardiovascular medications, reasons and barriers to deprescribing, and choice of medications to deprescribe in hypothetical clinical cases.

RESULTS

In each specialty, 750 physicians were surveyed, with a response rate of 26% for geriatricians, 26% for general internists, and 12% for cardiologists. Over 80% of respondents within each specialty reported that they had recently considered deprescribing a cardiovascular medication. Adverse drug reactions were the most common reason for deprescribing for all specialties. Geriatricians also commonly reported deprescribing in the setting of limited life expectancy. Barriers to deprescribing were shared across specialties and included concerns about interfering with other physicians' treatment plans and patient reluctance. In hypothetical cases, over 90% of physicians in each specialty chose to deprescribe when patients experienced adverse drug reactions. Geriatricians were most likely and cardiologists were least likely to consider deprescribing cardiovascular medications in cases of limited life expectancy (all P < .001), such as recurrent metastatic cancer (84% of geriatricians, 68% of general internists, and 45% of cardiologists), Alzheimer dementia (92% of geriatricians, 81% of general internists, and 59% of cardiologists), or significant functional impairment (83% of geriatricians, 68% of general internists, and 45% of cardiologists).

CONCLUSIONS

While barriers to deprescribing cardiovascular medications are shared across specialties, reasons for deprescribing, especially in the setting of limited life expectancy, varied. Implementing deprescribing will require improved processes for both physician-physician and physician-patient communication. J Am Geriatr Soc 68:78-86, 2019.

Cardiac Rehabilitation to Optimize Medication Regimens in Heart Failure

Cardiac rehabilitation (CR) is an inherently patient-centered program that provides holistic care to adults with cardiovascular conditions to promote lifelong health and fitness, facilitate self-care and self-efficacy, and improve clinical outcomes. CR offers an excellent platform for patient-centered optimization of medication regimens for older adults with heart failure through its potential to address several aspects of care that have historically served as major challenges to clinicians-diuretic management, the use of guideline-directed medical therapy, review and reconciliation of noncardiovascular medications, and optimization of medication adherence. In this review, these challenges are described and strategies offered for leveraging CR toward addressing them.

Evolution of Age and Female Representation in the Most-Cited Randomized Controlled Trials of Cardiology of the Last 20 Years

BACKGROUND

Older adults and women have historically been underrepresented in randomized controlled trials of cardiology. Recent temporal evolution and factors influencing representation are incompletely investigated. We aimed to contrast age and female representation in the most influential randomized controlled trials in cardiology of the last 20 years to population prevalence and to assess the study factors affecting representation.

METHODS AND RESULTS

Using Web of Science, we selected the 25 most-cited cardiology articles each year between 1996 and 2015, and extracted mean age, percentage of women, funding source, sample size, disease condition, intervention type, and exclusion criteria. The outcomes were the evolution of the mean age and the percentage of women over time. Protocol design elements and year of publication were assessed as predictors of outcomes in multivariable regressions. A total of 500 studies were analyzed, where the mean age was 62.6±7.4 years and the median percentage of women was 28.6% (22.2-40.5). Compared with population prevalence derived from National Health and Nutrition Examination Survey 2015-2016, gaps in representation were apparent and more pronounced for coronary artery disease (-5.0 years; -27.2% women) and heart failure (-6.0 years; -25.4% women). The mean age (0.15 year per year; 95% confidence interval, 0.04-0.26) and percentage of women (+0.29% per year; 95% confidence interval, 0.07-0.50), slightly but significantly increased over time. Private funding, small sample size, and exclusions pertaining to maximal age, atrial fibrillation, and diabetes mellitus were associated with a decreased mean age in multivariable linear regressions. Age and life expectancy exclusions were associated with lower female percentage.

CONCLUSIONS

Although age and female representation increased over time, the modest trends are unlikely to resolve the persistently wide gaps with actual populational prevalence, especially for coronary artery disease and HF. Representation is modulated by the cardiovascular condition studied and some modifiable protocol elements.

Association Between Functional Impairment and Medication Burden in Adults with Heart Failure

OBJECTIVES

To determine whether the number of medications taken by adults with heart failure (HF) and impairment in activities of daily living (ADL)-a subpopulation in whom the risks of a high medication burden may outweigh the benefits-differs from the number taken by those without impairment in ADLs.

DESIGN

Cross-sectional.

SETTING

National Health and Nutrition Examination Survey (NHANES; 2003-2014), a cross-sectional survey that produces national estimates of adults in the United States.

PARTICIPANTS

Adults aged 50 and older (mean 70) with self-reported HF (N= 947; representing 4.6 million adults with HF in the United States.

MEASURMENTS

We assessed ADL impairment and medication count based on self-report. ADL impairment was defined as having difficulty with or being unable to dress, feed oneself, or get in and out of bed. To determine the independent association between ADL impairment and medication count, we performed sequential Poisson multivariable regression analyses. All analyses were cross-sectional in nature and accounted for the complex survey design of NHANES.

RESULTS

Mean medication count was 7.2, and 74% of participants were taking 5 or more medications (polypharmacy). In a multivariable model, ADL impairment was not independently associated with medication count. These findings were similar for those with 3 or more hospitalizations in the prior year, declining health status, and cognitive impairment.

CONCLUSION

After adjusting for confounders including comorbidity, we found that adults with HF and ADL impairment take as many medications as those without ADL impairment. This suggests that providers may not sufficiently consider functional impairment when prescribing medications to adults with HF and thus may unnecessarily expose individuals to risk of adverse outcomes. J Am Geriatr Soc 67:284-291, 2019.

Time for a New Approach to Studying Older People with Ischemic Heart Disease

This editorial comments on the article by Bourgeois et al.