Addressing the Underrepresentation of Older Adults in Cancer CT: Advancing Inclusion for Improved Care
The underrepresentation of older patients in cancer clinical trials poses a significant concern as it limits the generalizability of trial results to the broader population, particularly older adults who are affected by cancer more frequently. Various factors contribute to the exclusion of older participants, including age-related eligibility criteria, preexisting conditions, polypharmacy, functional limitations, and exclusion from recruitment strategies.
This article explores the challenges associated with the underrepresentation of older adults in clinical trials and highlights recent efforts to address this issue.
Factors Affecting Inclusion of Older Patients in Clinical Trials
Age-related eligibility criteria: Clinical trials often have specific eligibility criteria that may exclude older individuals. These criteria may include age limits or restrictions based on comorbidities or organ dysfunction. Such criteria are often established to ensure patient safety and to maintain homogeneity within the trial population.
Presence of preexisting conditions: Older individuals have a higher likelihood of suffering from other health conditions, such as heart disease, diabetes, or kidney problems. These comorbidities can introduce additional complexities in evaluating the safety and efficacy of new cancer treatments. Researchers may be concerned that the presence of preexisting conditions could confound the study results or increase the risk of adverse events.
Polypharmacy: Older patients often take multiple medications to manage their health conditions. The potential interactions between these medications and the investigational treatment can be a concern in clinical trials. Researchers may exclude individuals who are on certain medications or have complex medication regimens to minimize potential risks and ensure accurate evaluation of the experimental treatment.
Functional limitations: Older patients may have physical limitations or reduced functional status, which can affect their ability to comply with trial requirements. For example, they may face challenges in traveling to trial sites or completing the necessary study procedures. These practical limitations may lead to exclusion from trials or make participation more burdensome for older individuals.
Underrepresentation in recruitment efforts: Recruitment strategies for clinical trials may not effectively reach older populations. Certain recruitment methods, such as online advertisements or social media campaigns, may not adequately target older individuals who are less likely to use these platforms. As a result, older patients may not be aware of or have access to clinical trial opportunities, leading to their underrepresentation.
Challenges in Treatment Optimization for Older Adults
In the absence of evidence from clinical trials, clinicians and patients have sought alternative ways to predict how age influences treatment response. In order to minimize side effects and optimize treatment outcomes in older adults, providers may adjust the dose or duration of treatment. However, these adjustments are often made without clear and specific guidance. The lack of comprehensive guidelines for the use across the spectrum of cancer treatments – from chemotherapy and radiation to immune checkpoint inhibitors – in older adults is a significant challenge in clinical practice.
Recent Developments and Initiatives
In March 2022, the FDA issued guidance to industry-funded trials, recommending the inclusion of older adults and relaxing other criteria to account for natural age-related declines. By promoting inclusivity and considering the age-related eligibility criteria and characteristics of older adults, the FDA’s guidance is aimed at improving treatment outcomes and at enhancing the quality of care for older individuals with cancer.
Organizations such as the Cancer and Aging Research Group (CARG) and the International Society of Geriatric Oncology (SIOG) are actively working to develop evidence-based guidelines and recommendations for the treatment of older adults with cancer. These organizations play a crucial role in bridging the gap in knowledge and addressing the unique challenges faced by older adults in the field of oncology. By promoting research, providing educational resources, and advocating for the inclusion of older adults in clinical trials, CARG, SIOG, and similar organizations contribute to the development of comprehensive and tailored guidelines for the treatment of older adults with cancer.
Since 2018, the American Society of Clinical Oncology has recommended the use of geriatric assessment to guide cancer care for older patients. Geriatric assessment is a comprehensive evaluation that assesses various domains of health in older adults, including physical function, cognition, psychological state, comorbidities, and social support. It helps clinicians identify potential vulnerabilities and tailor treatment plans accordingly. Integrating geriatric assessment into clinical practice is gaining momentum to better guide treatment decisions for older adults with cancer.
Conclusion
The underrepresentation of older patients in cancer clinical trials hinders our understanding of treatment outcomes and limits the applicability of trial results to this population. To overcome these challenges, ongoing efforts are focused on promoting research inclusivity, generating robust evidence, and developing comprehensive guidelines tailored to the unique needs of older adults. Enhancing the representation of older patients in clinical trials is crucial for advancing cancer treatment and improving the quality of care for this vulnerable population.
