Disparities in Genetic Testing for Inborn Errors of Immunity.

BACKGROUND

Inequities in genetic testing have been documented in a range of diseases, and no-charge genetic testing programs have been proposed as a means to enhance access. However, no studies have examined disparities in genetic testing for inborn errors of immunity (IEI) and the impact of no-charge programs on testing equity.

OBJECTIVE

To examine socioeconomic, geographic, and racial disparities in the uptake of genetic testing for IEI in the United States and the impact of a no-charge sponsored program on testing equity.

METHODS

This was a retrospective cohort analysis of (1) a national claims database capturing individuals with IEI (n = 18,603), and (2) data from a clinical genetic testing laboratory capturing patients with IEI participating in a no-charge sponsored program (n = 6,681) and a non-sponsored program (n = 29,579) for IEI genetic testing.

RESULTS

Among patients with IEI captured in the claims database, those residing in areas of greater deprivation (odds ratio [OR] = 0.95; 95% CI, 0.92-0.98), rural areas (OR = 0.82; 95% CI, 0.71-0.96), and non-White neighborhoods (OR = 0.89, 95% CI 0.81-0.98) were less likely to undergo genetic testing. Participants in the sponsored IEI genetic testing program lived in areas of greater deprivation compared with the non-sponsored program (median, 46 vs 42; P < .001). However, historically excluded racial groups were underrepresented in both the sponsored and non-sponsored programs relative to disease burden.

CONCLUSIONS

We found significant disparities in genetic testing for IEI. Although eliminating the financial barriers to testing reduced socioeconomic disparities in genetic testing for IEI, racial disparities persisted. Further research is needed to address barriers to testing among underserved populations.