Factors Affecting Rates of Genetic Testing for Inherited Retinal Degenerations

Abstract

Purpose : Factors affecting rates of genetic testing for inherited retinal degenerations have not been characterized. We analyzed effect of launch of the My Retina Tracker Genetic Testing Study (MRT-GTS) research registry and associations with patient characteristics.

Methods : We performed retrospective chart review of new patients evaluated at an eye center between July 2016 and June 2018, analyzing rates of genetic testing 12 months pre- and post-launch of MRT-GTS, which launched locally in June 2017. We determined odds ratios (ORs) of association between patient characteristics and rates of obtaining genetic testing. We examined the proportion of test results returned within 90 days of the initial clinic evaluation.

Results : Among 369 patients (age 39.5 years, SD 20.8), 144 were evaluated in the pre-MRT-GTS period and 225 in the post-period. The pre-MRT-GTS rate of successfully obtaining testing was 51.4% (95% CI, 42.6–60.2%). Post-launch, the testing rate increased by 28.9 percentage points (95% CI, 16.7–41.1%; P< .001). Patient factors that increased odds of testing were eligibility for MRT-GTS (OR, 14.15; 95% CI, 7.36–27.24; P< .001) and worse visual acuity (logMAR +1.0) in the better-seeing eye (OR, 1.92; 95% CI, 1.27–2.91; P< .01). Odds were decreased for those identifying as African-American (OR, 0.10; 95% CI, 0.04–0.24; P< .001) or other race (OR, 0.37; 95% CI, 0.15–0.91; P< .05), and when the primary language was not English (OR, 0.13; 95% CI, 0.03–0.55; P< .01). The proportion of test results reported within 90 days was 81.5% (95% CI, 74.8—86.4%) when eligible for MRT-GTS and 48.1% (95% CI, 35.6—58.1%) when not eligible (P< .001).

Conclusions : Demographic and clinical factors affect decisions to pursue genetic testing. There was an increase in testing rates after launch of MRT-GTS. Collaborations between non-profit organizations, industry, and the public sector to fund testing help to identify the genetic cause of disease, a critical stepping stone to developing therapies.

This is a 2021 ARVO Annual Meeting abstract.

 

Figure 1. Interrupted time series analysis of MRT-GTS spanning the 24 months pre- and post-launch. Broken line indicates program launch, with month of June 2017 (empty circle) excluded from regression analysis.

 

Figure 2. Patient characteristics associated with odds of obtaining genetic testing. For race, odds ratios are reported in relation to White. For insurance, odds ratios are reported in relation to no insurance.