Concerted efforts and substantial investments in HIV prevention and care in the United States have resulted in considerable reduction in new diagnoses and death since the mid-1990s. To identify best practices for prevention, NIDA has been funding research that explores the complex intersection of HIV/AIDS and substance use disorders, including the risks associated with injection drug use. However, despite the efforts of multiple public health organizations and research institutions, close to 38,000 new HIV cases were diagnosed in 2018, a reduction of only 7% from 2012. In addition, ethnic, racial, and sexual minorities have not fully benefited from advances in treatment and prevention. Progress has been hindered by health literacy deficits, stigma, and challenges in navigating the complex U.S. health system.
In 2019, the President of the United States set goals as part of the new initiative Ending the HIV Epidemic: A Plan for America to reduce new HIV infections by 75% within 5 years and by 90% within 10 years. To achieve these targets, the most recent National HIV/AIDS strategy calls for widespread testing and linkage to care; full access to medication services; broad support for people living with HIV; and universal viral suppression for people living with HIV. However, a NIDA funded economic modeling study has found that the current commitment will not be enough to reach targeted goals, suggesting that additional combinations of evidence based strategies will be needed to overcome the necessary social and structural barriers to HIV care.
For this study, investigators used a dynamic HIV transmission model calibrated with the best available evidence on epidemiological and structural conditions for six US cities: Atlanta (GA), Baltimore (MD), Los Angeles (CA), Miami (FL), New York City (NY), and Seattle (WA). They assessed more than 23,000 combinations of 16 evidence-based interventions to identify which combinations would provide the greatest health benefit while remaining cost-effective. These interventions include HIV prevention strategies, testing, treatment, engagement, and re-engagement. To address the HIV epidemic in people who use drugs, all models included medications for opioid use disorders as part of treatment.
Main outcomes measured include averted HIV infections; quality-adjusted life-years; total cost; and incremental cost-effectiveness ratio calculated from the health-care sector perspective. The modeling included estimates of the ideal scale-up of interventions, sustained from 2020 to 2030, with outcomes evaluated until 2040.
The investigators concluded that existing plans can reduce new diagnoses, but will not meet targeted goals. For example, if implemented at the previously planned scale-up, current strategies could reduce incidence by about 31% in Seattle and 50% in New York City by 2030. At ideal implementation, however, the model showed that incidence reductions reached about 40% in Seattle and 84% in Baltimore. They also found that in the city of Seattle, it would take nine combination interventions to reach optimal goals, and 13 in Miami. In no city did they find that targets could be met without implementation of interventions at scales of delivery not previously recorded. Although reaching these targets would require nearly double the levels of funding than what has been proposed, costs could be offset by long-term reductions in new infections and delayed disease progression, with Atlanta, Baltimore, and Miami projecting cost savings over the 20 year study period.
Since cost effective outcomes included the use of evidence based medications for opioid use disorders, this research confirms that treating substance use disorders contributes to reducing HIV burden. These findings can help inform the public health community as the nation evaluates future policy directions.
The investigators are part of the Localized HIV Modeling Study Group, a group of HIV investigators from multiple research institutions in the U.S. and Canada.
Study:
- Bohdan Nosyk, Xiao Zang, Emanuel Krebs, Benjamin Enns, Jeong E Min, Czarina N Behrends, Carlos del Rio, Julia C Dombrowski, Daniel J Feaster, Matthew Golden, Brandon D L Marshall, Shruti H Mehta, Lisa R Metsch, Ankur Pandya, Bruce R Schackman, Steven Shoptaw, Steffanie A Strathdee, on behalf of the Localized HIV Modeling Study Group. Ending the HIV epidemic in the USA: an economic modelling study in six cities . The Lancet.