Streptococcal infections in adolescents and adults after prolonged freedom from rheumatic fever; results of the first three years of the study

Will Genetic Testing Alter the Management of Disease Caused by Infectious Agents? A Cost‐Effectiveness Analysis of Gene‐Testing Strategies for Prevention of Rheumatic Fever

“…For the general low-risk population, age-dependent streptococcal pharyngitis attack rates (and the conditional probability of developing acute RF, given the presence of streptococcal upper respiratory tract infection) were derived from a prospective community study [25], and model results were compared with the cumulative risk of RF reported from the Framingham Study [39]. Attack rates for high-risk individuals were derived from prospective studies of the incidence of pharyngitis and the rate of recurrence of RF among patients with a prior history of RF [29,31]. The probability of death due to acute RF and that of progression to chronic valvular heart disease or congestive heart failure were derived from a prospective cohort study [31], a cross-sectional study [39], and a recent case series [32].…”

“…Sensitivity analyses included the following variations: (1) the cost of genetic testing was varied from $5 to $5000 on the basis of the complexity of the testing; (2) the prevalence of genetic susceptibility to acute RF was varied from 1% to 20% [12,13,17]; (3) the sensitivity and specificity of genetic testing were varied from 70% to 99% and from 65% to 99%, respectively; (4) the cost of treating streptococcal pharyngitis, the cost of RF prophylaxis, and the costs of acute RF without sequelae and RF with valvular complications were varied from 50% to 200% of their baseline values; (5) the probability of RF following streptococcal pharyngitis in high-risk patients was varied from 3.5% to 15% [19,22,29]; (6) the probability of streptococcal pharyngitis among those given prophylaxis ranged from 0.3% to 8.5%; and (7) the discount rate (which was the same for both costs and benefits [21]) was varied from 3% to 7%. The nature and costs of cardiac care have changed dramatically during the past few decades, and it is difficult to predict costs several decades in advance.…”