Disabilities in people with heart disease underreported in clinical trials

Reviewed by Emily Henderson, B.Sc.Feb 23 2023

Disabilities were underreported in clinical trial data and commonly used as a basis for exclusion from trial participation in an analysis of 80 recent trials involving cardiovascular outcomes, according to a study being presented at the American College of Cardiology's Annual Scientific Session Together With the World Congress of Cardiology.

Reports estimate that over half of people with heart disease have one or more disabilities related to cognition, mobility, vision, independent living, self-care or hearing as defined by the Centers for Disease Control and Prevention (CDC). However, the new study found that 38% of clinical trials listed a disability among their exclusion criteria and only 8% of trials reported disability status as part of their baseline data. Researchers said these gaps in both inclusion and reporting suggest clinical trial designers are missing an opportunity to ensure studies adequately represent the patient populations they intend to benefit.

We were surprised that there was this lack of reporting for disabilities, simply because doing so is CDC guideline recommended, and it would be a valuable data point for clinicians. I hope our study can jump-start an effort to increase reporting of disabilities, both in baseline patient demographics and also outcomes."

Roy Lan, MD, internal medicine resident at Stanford University and study's lead author

The study is the first to specifically examine reporting and inclusion of people with disabilities within cardiovascular clinical trials. Across all 80 trials, only six included data on disabilities in published baseline participant characteristics, an omission that may be due to a lack of data collection, a lack of data reporting or both.

"There is an abundance of literature within cardiovascular trials on race, ethnicity and gender, but people with disabilities are another population that can be vulnerable," Lan said. "As we become more advanced in targeting therapies to different population groups, this is one that we really can't forget and need to serve well. If we aren't even reporting disabilities in clinical trials, how can we best serve and take care of these patients?"

Researchers analyzed the 20 most recently published clinical trials in each of four major areas: atrial fibrillation, coronary artery disease, hypertension and diabetes. Only trials for which full published data were available were included in the sample, and all studies were published between 2014 and 2022. The researchers assessed disabilities reporting and exclusion criteria based on each trial's published data as well as records from the clinical trials database (ClinicalTrials.gov).

Overall, 38% of the trials listed at least one type of disability among their exclusion criteria. Of the different types of trials, disabilities were cited in exclusion criteria most often in hypertension trials (55%) and least often in diabetes trials (15%).

Disabilities related to cognition or psychiatric issues (such as Alzheimer's disease or other forms of dementia) were the most common type of excluded disability with one-third of trials citing this in the exclusion criteria. Between 3%-8% of trials excluded disabilities related to mobility, vision, independent living, self-care or hearing. Although the CDC provides specific criteria for defining six categories of disability, researchers noted that many clinical trials established their own definitions of disability, potentially leading to greater exclusion and making it difficult to compare results across studies.

Future studies could help to elucidate why people with certain types of disabilities are often excluded from clinical trial participation and guide efforts to design trials that are more inclusive, researchers said. They suggest it would also be useful to more routinely include information about disability status in clinical trial data, as well as capture the degree of disability at baseline to allow researchers to track any changes over the course of the trial.

In a separate study being presented at the meeting, researchers found that people with intellectual disabilities (limitations in the ability to learn at an expected level and function in daily life) who were hospitalized for acute coronary syndrome were significantly less likely to receive coronary angiography or revascularization and more likely to die in the hospital than people without intellectual disabilities. The findings point to a need to address disability-related disparities in patient care in addition to clinical trial design and practice. The trial, "Outcomes of Acute Coronary Syndrome in Patients with Intellectual Disabilities: Insights from the National Inpatient Sample," will be simultaneously published in Cardiovascular Revascularization Medicine.