Abstract Body: Introduction:
The HeartShare Network aims to improve understanding of heart failure with preserved ejection fraction (HFpEF), a condition that disproportionately affects those with adverse social determinants of health. Ensuring diverse recruitment is key to advancing HFpEF research. This study examines response rates of various recruitment approaches across sociodemographic groups at a single HeartShare Clinical Center for an online registry including patients with and without HFpEF.

Hypothesis:
We hypothesized that electronic health record (EHR) messaging would be more effective in recruiting a diverse group of participants compared to telephone and in-person outreach.

Methods:
This observational study recruited patients aged 30 years and older between 8/1/2023-8/1/2024 from a tertiary-care academic center (Northwestern Medicine). Participants were contacted via phone calls, EHR portal messages, and in-person outreach. Data on age, race, and ethnicity were collected. Area Deprivation Index (ADI) was calculated using addresses. Statistical analyses, including Fisher’s Exact Test, were conducted using R to assess differences in recruitment rates across demographic groups and recruitment methods.

Results:
Among 8,080 patients contacted through EHR messaging, 144 (1.8%) enrolled in the online registry. In comparison, among 1,439 participants contacted via phone, 174 (12.1%) enrolled and among 193 approached in-person, 79 (41%) enrolled. Response rates (consenting after contact) varied for each approach by race and ethnicity (p<0.001). White participants had a response rate of 14% (after phone contact), 2% (after EHR contact), and 54% (after in-person contact). Black participants had a response rate of 6% (phone), <1% (EHR), and 49% (in-person). Hispanic participants had response rates of 5% (phone), <1% (EHR), and 38% (in-person). Among the enrolled, participants from the most deprived areas (ADI 5th quintile) were most effectively recruited through in-person methods compared with those from the least deprived quintile who were most successfully recruited via phone.

Conclusion:
While more individuals were contacted through EHR-based messaging, response rates were lower, especially among Black and Hispanic participants. In-person recruitment was the most successful in engaging minoritized populations or those residing in more deprived areas. Future studies should explore ways to improve response rates among diverse populations using EHR approaches.