Racial and Ethnic Disparities at Enrollment in DRCRnet Clinical Trials for Diabetic Macular Edema

To assess racial/ethnic disparities and association with diabetic macular edema (DME) characteristics at enrollment in DRCR Retina Network (DRCRnet) DME clinical trials.

Retrospective, cross-sectional analysis of data from DRCRnet clinical trials.

5468 participants in 17 DRCRnet DME trials (2003-2020).

The racial and ethnic distribution of DRCRnet DME trial participants was compared to United States census data and DME prevalence data in the CDC's Vision and Eye Health Surveillance System (VEHSS). Generalized linear models were used for comparing demographics, HgbA1c, diabetic retinopathy (DR) severity, and visual acuity (VA) among racial/ethnic groups, and for determining factors associated with VA.

Racial and ethnic distribution of DME trial participants; patient and ocular characteristics at enrollment.

Compared to VEHSS (64% White, 16% Black, 4% Asian, 14% Hispanic) and the 2020 U.S. census (62% White, 12% Black, 6% Asian, 19% Hispanic), White (76%) participants were over-represented, and Asians (2%) and Hispanics (12%) were under-represented (P < .001) in DME trials. HgbA1c was higher in Black and Hispanic (8.3) than in White (7.7) and Asian (7.6) participants (P < .001). More Asian (20%) and Hispanic (23%) participants had proliferative DR than White (19%) and Black (15%) participants (P < .001). Hispanic ethnicity, female gender, older age at diabetes diagnosis, and severe DR were independently associated with worse VA (all P < .05).

Hispanic participants, while under-represented, had higher HgbA1c, more severe DR, and worse VA than other groups, emphasizing the need for diverse recruitment in DME trials.