Estimating the cost-effectiveness of a national program to eliminate disparities in influenza vaccination rates among elderly minority groups.

Influenza is a major cause of preventable morbidity and mortality in the United States, particularly among the elderly. Yet, there remain large disparities in influenza vaccination rates across elderly Caucasian (70%), African-American (50%) and Hispanic (55%) populations, with substantial mortality consequences. In this study, we built a decision-analysis model to estimate the cost-effectiveness of a hypothetical national vaccination program designed to eliminate these disparities in influenza vaccination rates. Taking a societal perspective, we developed a Markov model with a one-year cycle length and lifetime time horizon. In the base case, we conservatively assumed that the cost of promoting the vaccination program was $10 per targeted elder per year and that by year 10, the vaccination rate of the elderly African-American and Hispanic populations would equal the vaccination rate of the elderly Caucasian population (70%). The cost-effectiveness of the vaccination program compared to no vaccination program was $48,617 per QALY saved. Probabilistic sensitivity analyses suggested that at willingness-to-pay thresholds of $50,000 and $100,000 per QALY saved, the likelihood of the vaccination program being cost-effective was 38% and 92%, respectively. In an analysis using conservative assumptions, we found that a hypothetical program to ameliorate disparities in influenza vaccination rates has a moderate to high likelihood of being cost-effective.