Cost-effectiveness of vaccination against invasive pneumococcal disease among people 50 through 64 years of age: role of comorbid conditions and race.

BACKGROUND: Guidelines are increasingly recommending preventive services starting at 50 years of age, and policymakers are considering such a recommendation for pneumococcal polysaccharide vaccination. The finding that pneumococcal vaccination is cost-saving for people 65 years of age or older raises the question of the vaccination's implications for other older adults, especially black people, whose disease incidence exceeds that of nonblack people, and those with high-risk conditions.
OBJECTIVE: To assess the implications of vaccinating black and nonblack people 50 through 64 years of age against invasive pneumococcal disease.
DESIGN: Cost-effectiveness analysis. DATA SOURCES: Published literature for vaccination effectiveness and cost estimates; data on disease incidence and case-fatality rates from the Centers for Disease Control and Prevention. TARGET POPULATION: Hypothetical cohort 50 through 64 years of age with the 1995 U.S. age distribution. TIME HORIZON: Lifetime. PERSPECTIVE: Societal. INTERVENTION: Pneumococcal polysaccharide vaccination compared with no vaccination. OUTCOME MEASURES: Incremental medical costs and health effects, in quality-adjusted life-years per vaccinee. RESULTS OF BASE-CASE ANALYSIS: Vaccination saved medical costs and improved health among high-risk black people (27.55 dollars savings per vaccinee) and nonblack people (5.92 dollars savings per vaccinee), excluding survivors' future costs. For low-risk black and nonblack people and the overall general population, vaccination cost 2477 dollars, 8195 dollars, and 3434 dollars, respectively, to gain 1 year of healthy life. RESULTS OF SENSITIVITY ANALYSIS: Excluding survivors' future costs, in the general immunocompetent population, cost per quality-adjusted life-year in global worst-case results ranged from 21 513 dollars for black people to 68 871 dollars for nonblack people; in the high-risk population, cost ranged from 11 548 dollars for black people to 39 000 dollars for nonblack people. In the global best case, vaccination was cost-saving for black and nonblack people in the general immunocompetent and high-risk populations, excluding survivors' future costs. The cost-effectiveness range was narrower in probabilistic sensitivity analyses, with 95% probabilistic intervals ranging from cost-saving to 1594 dollars for black people and from cost-saving to 12 273 dollars for nonblack people in the general immunocompetent population. Costs per quality-adjusted life-year for low-risk people with case-fatality rates from 1998 were 2477 dollars for black people and 8195 dollars for nonblack people, excluding survivors' medical costs.
CONCLUSIONS: These results support the current recommendation to vaccinate high-risk people and provide useful information for considering extending the recommendation to the general population 50 through 64 years of age. Lack of evidence about the effectiveness of revaccination for people 65 years of age or older, when disease risks are higher, argues for further research to guide vaccination policy.