Financial strain may explain attrition for some patients in clinical trials
Signs of social vulnerability such as income, insurance status and race were potentially indicative of participants at risk for loss to follow-up in clinical trials, researchers reported.
An analysis of the HYVALUE trial, published in Circulation: Cardiovascular Quality and Outcomes, demonstrated that financial-resource strain may be an independent predictor of partial or full participant attrition in the clinical trial, independent of race and gender.
“Underrepresented groups in the United States, such as members of racial and ethnic minority groups and women, often face health and health care inequities and representation of socially vulnerable populations is important to the generalizability of research findings,” Kamal H. Henderson, MD, MSc, internal medicine specialist at the University of North Carolina Institute for Healthcare Quality Improvement, and colleagues wrote. “Recruitment practices to improve participation of women and ethnic and racial minorities in research studies has been the primary focus in biomedical research to improve diversity in representation of research participants. However, little is known about a potentially related problem, differential attrition of socially vulnerable participants after study enrollment.”
To better understand the factors associated with participant attrition, researchers conducted an analysis of adults with uncontrolled hypertension enrolled in the HYVALUE trial, a randomized trial that assessed values affirmation on medication adherence by targeting racial stereotype threat.
The main results of the HYVALUE trial were published in JAMA Network Open. Researchers determined that, although values affirmation increased patient activation overall, it did not improve medication adherence or BP among Black or white patients with uncontrolled hypertension.
For the present analysis of the HYVALUE trial, researchers evaluated the effects of the following indicators of social vulnerability on participant attrition: Black race, female gender, no health insurance, unemployment, high school education and financial-resource strain.
Social vulnerability and trial attrition
Among 825 participants (mean age, 63 years; 60% women; 54% Black), 97% self-reported at least one indicator of social vulnerability.
Full attrition was observed in 21% of HYVALUE trial participants after study enrollment.
After adjustment for all social vulnerabilities, researchers reported that financial-resource strain was the only vulnerability consistently associated with full attrition (RR = 1.71; 95% CI, 1.28-2.29).
Among participants who completed only one follow-up visit, both financial-resource strain (RR = 1.4; 95% CI, 1.09-1.81) and lack of insurance (RR = 1.54; 95% CI, 1.01-2.34) were associated with partial attrition compared with no attrition.
Moreover, in a secondary analysis of risk for full attrition compared with no attrition, financial-resource strain (RR = 1.83; 95% CI, 1.39-2.4) and Black race (RR = 1.33; 95% CI, 1.02-1.74) were associated with full attrition.
“We found that financial-resource strain — difficulty paying for the basics in the last 3 months — was consistently associated with a higher risk of partial or full attrition after adjusting for all other social vulnerability indicators,” the researchers wrote. “In a population with a high burden of social vulnerabilities, our study suggests that when controlling for other social vulnerability indicators, financial-resource strain remained consistently associated with complete loss to follow-up.”
‘Trial representation is more than surface deep’
In a related editorial, Sachin J. Shah, MD, MPH, internist, clinical epidemiologist and assistant professor of medicine at the University of California, San Francisco, and Utibe R. Essien, MD, MPH, internal medicine physician and health equity researcher at the University of Pittsburgh, discussed how the findings may inform the enrollment and representation in future clinical trials.
“The study findings urge us to redefine how we assess trial representativeness,” the authors of the editorial wrote. “Glancing at the traditional Table 1 to see if the participant characteristics match the general population seems insufficient.
“Trial representation is more than surface deep. Diverse representation in trial enrollment must closely be followed by equity in trial completion,” the authors wrote. “Reporting differential attrition is the first (and smallest) step toward ensuring randomized trials can effectively advance equitable cardiovascular care over the next 70 years.”
- Daugherty SL, et al. JAMA Netw Open. 2021;doi:10.1001/jamanetworkopen.2021.39533.
- Shah JS, et al. Circ Cardiovasc Qual Outcomes. 2022;doi:10.1161/CIRCOUTCOMES.121.008726.