Neighborhood Social Capital and Distance from Facility Predict Consenting to Participate in a Clinical Trial among Cancer Patients

Authors: McIntire R, Keith S, Nowlan T, Butt S, Cambareri K, Chandrasekar T, Kelly WK, Leader A

Category: Survivorship & Health Outcomes/Comparative Effectiveness Research
Conference Year: 2020

Abstract Body:
Purpose: This study identified demographic, clinical, geographic, and neighborhood predictors of consenting to trial participation among cancer patients in an urban cancer center. Methods: We selected all patients with new diagnoses of cancer during 2015-2017 from an institutional cancer registry. We linked patient demographics and clinical data to information on trials participation. We geocoded patient addresses, limited the dataset to patients that resided in Philadelphia (N=3254), and joined an index describing patients’ neighborhood-level social capital. We calculated driving distance between each patients’ residence and the cancer center. We used generalized linear mixed effects conditional logistic regression models to identify the individual and neighborhood correlates of consenting to participate in a clinical trial. Results: Compared to patients under age 50, those 50-69 had higher odds of consenting to a clinical trial (AOR=1.42) while patients age 80+ had lower odds of consenting (AOR=0.36). Non-Hispanic (NH) Asian patients had lower odds of consenting compared to NH-Whites (AOR=0.51). Compared to patients with other solid tumor cancer types, those with breast cancer had nearly a 4-fold higher odds of consenting (AOR=3.87) and those with hematologic cancer had 2-fold higher odds of consenting (AOR=2.12). Compared to patients with local stage cancer, those with regional stage cancer had higher odds of consenting (AOR=1.79). Interestingly, each kilometer of driving distance from a patient’s residence to the trials facility was associated with a 4% increase in odds of consenting (AOR=1.04). Compared to patients who live in neighborhoods in the lowest quartile of our sample’s social capital index, those in the 2nd quartile had a 35% higher odds of consenting (AOR=1.35) and those in the highest quartile had a 50% higher odds of consenting (AOR=1.50). Conclusions: We found geographic and neighborhood-level predictors of consenting to clinical trials among cancer patients. Residential distance from the cancer center was inversely related to consenting to trials. Patients living in neighborhoods with higher social capital had higher odds of consenting. These results can inform cancer center programs to improve patient participation in clinical trials.

Keywords: Clinical trials, geography, neighborhood