Panel Paper: Does Providing Insurance Coverage Reduce the Spread of Infectious Disease? the Impact of Medicaid Expansions on HIV Diagnoses.

Saturday, November 9, 2019
I.M Pei Tower: Majestic Level, Vail (Sheraton Denver Downtown)

*Names in bold indicate Presenter

Alex Hollingsworth1, Shyam Raman1, Dan Sacks1 and Katherine Wen2, (1)Indiana University, (2)Cornell University

Preventing the spread of infectious disease—a classic externality—is a textbook justification for intervention in the health care and health insurance markets. Yet little evidence exists on whether government-induced increases in insurance coverage affect the spread of infectious disease. This paper aims to study the impact of Medicaid expansions on the rate of new HIV diagnoses by evaluating the impact of insurance coverage expansions on usage of preventative, prophylactic treatment. We use state-level data on prescription drug utilization to assess the impact of ACA-facilitated Medicaid expansions on the utilization of pre-exposure prophylaxis (PrEP), estimating difference-in-difference regressions with state and year-level fixed effects. We find evidence that Medicaid expansion is associated with large, significant increases in the use of PrEP, a highly expensive drug regime that effectively prevents HIV acquisition. This increased use of PrEP was effective: we find that Medicaid expansion is associated with 5 percent decrease in the rate of new HIV diagnoses. PrEP prescriptions require regular HIV testing, consistent with this we find evidence of an increase in the percent of those who were recently tested for HIV.