177 - Rare Diseases, Common Barriers: Disparities in Clinical Genetics Outcomes

Poster Number: 177
Publication Number: 177.412

Monica H. Wojcik, Boston Children's Hospital, Wellesley, MA, United States; Mairead A. Bresnahan, Boston Children's Hospital, Marblehead, MA, United States; Maya C. del Rosario, Boston Children's Hospital, Boston, MA, United States; Mayra Martinez Ojeda, Boston Children's Hospital, Brookline, MA, United States; Amy Kritzer, Boston Children's Hospital, Boston, MA, United States; Yarden S. Fraiman, Beth Israel Deaconess Medical Center/Boston Children's Hospital/Harvard Medical School, Boston, MA, United States

Background: Identifying a precise genetic diagnosis can be life-changing for individuals with rare disease, though the resources required to do so may impede access and exacerbate healthcare disparities leading to inequitable care.

Objective: To determine the effect of multiple sociodemographic factors on the yield of the diagnostic evaluation for genetics outpatients.

Design/Methods: Retrospective cohort study of all outpatient genetics referrals in 2017 at a pediatric academic tertiary care center in an urban setting. The primary exposure evaluated was individual-level Childhood Opportunity Index 2.0 (COI) quintile. Other measured exposures included primary language, ancestry, insurance type, and reason for genetics evaluation. The primary outcome was identification of a laboratory-confirmed genetic diagnosis within 2 years of the initial clinic visit. Secondary outcomes were age at diagnosis and intermediate steps in the genetic diagnostic odyssey.

Results: Of 1859 outpatient genetics visits scheduled, 413 resulted in cancellations or no shows. State-normed COI quintile was significantly associated with clinic attendance, with the lower quintiles comprising a higher proportion of incomplete referrals (Table 1).

Of attended visits, 929/1446 (64.2%) were for the purpose of diagnostic evaluation. The overall diagnostic yield was 176/929 (18.9%). No differences were found in diagnostic yield across COI quintiles, ancestry categories, or by insurance type. Those who had a confirmed diagnosis had a significantly lower age at first clinic visit (2.1 [IQR 0.5-7.4] vs 3.3 [IQR 1.0-7.8], p = 0.004) and were more likely to be Arabic-speaking (Table 2). There was also significant variation in sociodemographic features and diagnostic yield across reasons for visit. After controlling for reason for visit and age at first visit, both Arabic and Spanish-speaking families had a higher odds of diagnosis than English speakers (Table 2).

In a subsequent exploratory analysis, we found that genetic testing was sent more often for families with public insurance or who were Spanish-speaking, though these families were less likely to have exome sequencing sent. We identified an older median age at diagnosis for those with limited English proficiency.Conclusion(s): The primary barrier to identification of a genetic diagnosis was initiation of care rather than the ensuing care cascade. Our findings suggest delays in care and referral bias leading to more severe phenotypes among families with limited English proficiency. Improved access to clinical genetics is needed in order to address inequities related to genetic diagnosis.
Conceptual modelThe relationship between various social determinants of health and the primary outcome of genetic diagnosis. Yellow circles indicate exposures analyzed as possible predictors of the outcome (green circle). Blue circles indicate possible confounders. The dashed arrow reflects that race is a social construct that may overlap with genetic ancestry.
Table 1.