Abstract 4402: Cost-effectiveness of Genetic Testing in Family Members of Patients with Long QT Syndrome
Background: Long QT syndrome (LQTS) is associated with mutations in one of several genes and follows Mendelian patterns of inheritance with incomplete penetrance Family members of patients with LQTS often do not manifest definitive EKG findings but remain at risk of sudden death. Commercially available genetic testing can identify mutations in 75% of patients with definite LQTS, but the role of genetic testing in the management of family members is controversial.
Methods: We created a Markov model of cost, quality of life and survival in LQTS to assess the cost-effectiveness of using genetic testing in the management of unaffected first degree relatives of patients with clinically evident LQTS (Scwhartz score ≥ 4). In the genetic testing scenario we assumed the index case would undergo genetic testing, and if a mutation was identified, then first degree relatives without definitive diagnosis of LQTS would be tested for the culprit mutation and those with the mutation would be treated with beta-blockers. The genetic testing strategy was compared with
a strategy of prophylactic treatment with beta blockers, and
a strategy of watchful waiting without treatment until the onset of symptoms.
In all scenarios patients who had recurrent syncope on beta-blockers were treated with an ICD.
Results: In the genetic testing scenario family members had better survival and quality of life (24.1 vs. 23.53 quality adjusted life years (QALY)) and higher costs ($25,202 versus $18,322) compared with the strategy of watchful waiting without treatment. The genetic testing strategy was cost-effective with $12,924 per QALY gained, had better outcomes and had lower costs than the strategy of prophylactic treatment with beta-blockers.
Conclusions: Providing genetic testing to families where one member is definitively diagnosed with LQTS is highly cost-effective from a societal perspective at $12,924 per quality-adjusted life year gained.