Mainstreaming Genomic Testing to Increase Diagnostic Accessibility for Adults with Intellectual and Developmental Disabilities
Health Services and Implementation
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Primary Categories:
- Health services and Implementation
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Secondary Categories:
- Health services and Implementation
Introduction:
Genomic testing, including whole exome sequencing (WES), has revolutionized the diagnosis of genetic conditions, and led to improved health outcomes, healthcare cost savings, and psychosocial benefits. Access to genomic testing is constrained by genetics workforce limitations, clinician knowledge gaps, and financial barriers. Integrating genetic testing into routine medical care, a process known as mainstreaming, has increased access to molecular testing for a number of conditions, including breast cancer, pharmacogenetic risk, and polycystic kidney disease. Despite clear benefits, mainstreaming broader, more unbiased genomic testing (beyond single or limited-gene disorders) has not been accomplished due to the scope and complexity of consent, insurance coverage, and result analysis.
Genomic testing is the recommended first-line care for pediatric patients with intellectual and developmental disabilities (IDD). There are no standardized guidelines for offering genomic testing for adults with IDD, despite the likely high prevalence of Mendelian conditions and the presence of substantial health-related disparities. The significant social inequities in knowledge of genetic testing are magnified for adults, especially those in underrepresented communities. Mainstreaming genetics into primary care may alleviate these disparities and provide clinic benefits to this underserved population.
Methods:
Patients in a clinic dedicated to adults with IDD were offered WES during their primary care appointments. Uptake, diagnostic yield, and clinical outcomes were tracked. Attitude and knowledge towards genetic testing were measured using a mixed methods approach. Focus groups were conducted with clinicians specializing in adult developmental medicine to identify barriers and facilitators of mainstreaming genomic testing.
Results:
WES was offered to 32 patients, aged 16-45 years-old, over a 6-month period. Uptake was 90.6% with 29 individuals opting for testing (4 as Proband only, 13 as Duos, 8 as Trios, 4 as Quads). 53.5% of patients receiving testing were of Black or Latino ancestry. WES identified a pathogenic or likely pathogenic variant in 11 patients (34.4%), variants of uncertain significance in 7 patients (21.8%), and candidate genes in 3 patients (9.4%). New genetic diagnoses resulted in medication changes for 2 patients, clinical trial eligibility for 3 patients, and new familial diagnoses in 3 patients. Two patients were included in a clinical cohort as adult representatives of a condition previously considered lethal in early childhood. Semi-structured interviews with caregivers showed a mix of emotions from appreciation about new guidance for care, excitement about new access to psychosocial support, and disappointment that a diagnosis was not made sooner. Patients within this clinic already had maximized social supports and no significant change was measured following a genetic diagnosis.
Ten clinicians participated in focus groups, including physicians, nurses, social workers, and developmental medicine trainees. All participants endorsed the importance of genetic testing and described perceived benefits throughout the lifespan. They believed that easier access to testing would improve their patients’ health and their quality of care. However, their clinics could not support this testing with their current workflow. Barriers included uncertainty about the consent process, too much paperwork (i.e. prior authorizations), and inability to interpret results, specifically variants of uncertain significance. Two respondents reported that their institution explored hiring a genetic counselor to embed in the adult developmental medicine clinics, but neither finalized the process.
Conclusion:
Integrating genomic testing into routine medical care is likely to improve access and reduce health care disparities for high-risk populations. The benefits of genomic testing may be age-independent and greater guidance is needed to define the role of genomic testing in adults. Our current healthcare systems are not designed for successful mainstreaming of genomic testing. New models that incorporate genetics professionals into routine medical practice may facilitate scaling mainstream genomic testing in a sustainable manner.
Genomic testing, including whole exome sequencing (WES), has revolutionized the diagnosis of genetic conditions, and led to improved health outcomes, healthcare cost savings, and psychosocial benefits. Access to genomic testing is constrained by genetics workforce limitations, clinician knowledge gaps, and financial barriers. Integrating genetic testing into routine medical care, a process known as mainstreaming, has increased access to molecular testing for a number of conditions, including breast cancer, pharmacogenetic risk, and polycystic kidney disease. Despite clear benefits, mainstreaming broader, more unbiased genomic testing (beyond single or limited-gene disorders) has not been accomplished due to the scope and complexity of consent, insurance coverage, and result analysis.
Genomic testing is the recommended first-line care for pediatric patients with intellectual and developmental disabilities (IDD). There are no standardized guidelines for offering genomic testing for adults with IDD, despite the likely high prevalence of Mendelian conditions and the presence of substantial health-related disparities. The significant social inequities in knowledge of genetic testing are magnified for adults, especially those in underrepresented communities. Mainstreaming genetics into primary care may alleviate these disparities and provide clinic benefits to this underserved population.
Methods:
Patients in a clinic dedicated to adults with IDD were offered WES during their primary care appointments. Uptake, diagnostic yield, and clinical outcomes were tracked. Attitude and knowledge towards genetic testing were measured using a mixed methods approach. Focus groups were conducted with clinicians specializing in adult developmental medicine to identify barriers and facilitators of mainstreaming genomic testing.
Results:
WES was offered to 32 patients, aged 16-45 years-old, over a 6-month period. Uptake was 90.6% with 29 individuals opting for testing (4 as Proband only, 13 as Duos, 8 as Trios, 4 as Quads). 53.5% of patients receiving testing were of Black or Latino ancestry. WES identified a pathogenic or likely pathogenic variant in 11 patients (34.4%), variants of uncertain significance in 7 patients (21.8%), and candidate genes in 3 patients (9.4%). New genetic diagnoses resulted in medication changes for 2 patients, clinical trial eligibility for 3 patients, and new familial diagnoses in 3 patients. Two patients were included in a clinical cohort as adult representatives of a condition previously considered lethal in early childhood. Semi-structured interviews with caregivers showed a mix of emotions from appreciation about new guidance for care, excitement about new access to psychosocial support, and disappointment that a diagnosis was not made sooner. Patients within this clinic already had maximized social supports and no significant change was measured following a genetic diagnosis.
Ten clinicians participated in focus groups, including physicians, nurses, social workers, and developmental medicine trainees. All participants endorsed the importance of genetic testing and described perceived benefits throughout the lifespan. They believed that easier access to testing would improve their patients’ health and their quality of care. However, their clinics could not support this testing with their current workflow. Barriers included uncertainty about the consent process, too much paperwork (i.e. prior authorizations), and inability to interpret results, specifically variants of uncertain significance. Two respondents reported that their institution explored hiring a genetic counselor to embed in the adult developmental medicine clinics, but neither finalized the process.
Conclusion:
Integrating genomic testing into routine medical care is likely to improve access and reduce health care disparities for high-risk populations. The benefits of genomic testing may be age-independent and greater guidance is needed to define the role of genomic testing in adults. Our current healthcare systems are not designed for successful mainstreaming of genomic testing. New models that incorporate genetics professionals into routine medical practice may facilitate scaling mainstream genomic testing in a sustainable manner.