Crystal Clear? The Relationship Between Methamphetamine Use and Sexually Transmitted Infections

• Published in: Health economics Vol. 25; no. 3; pp. 292 - 313
• Main Authors: Mialon, Hugo M., Nesson, Erik T., Samuel, Michael C.
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.03.2016; Wiley Periodicals Inc
• Subjects: Amphetamine-Related Disorders - epidemiology; California - epidemiology; Chlamydia; Chlamydia Infections - epidemiology; Chlamydia trachomatis; ephedrine; Female; Gonorrhea; Gonorrhea - epidemiology; HIV; Human immunodeficiency virus; Humans; Infections; Male; Methamphetamine; Public health; Risk behavior; Risk-Taking; risky sexual behavior; Safe sexual practices; Sexual Behavior; Sexually transmitted diseases; Sexually Transmitted Diseases - epidemiology; sexually transmitted infections; STD; substance use; supply shock; Syphilis; Syphilis - epidemiology; United States > US; substance use; ephedrine; sexually transmitted infections; gonorrhea; methamphetamine; chlamydia; risky sexual behavior; supply shock; syphilis
• ISSN: 1057-9230; 1099-1050
• DOI: 10.1002/hec.3140

Summary Public health officials have cited methamphetamine control as a tool with which to decrease HIV and other sexually transmitted infections, based on previous research that finds a strong positive correlation between methamphetamine use and risky sexual behavior. However, the observed correlation may not be causal, as both methamphetamine use and risky sexual behavior could be driven by a third factor, such as a preference for risky behavior. We estimate the effect of methamphetamine use on risky sexual behavior using monthly data on syphilis diagnoses in California and quarterly data on syphilis, gonorrhea, and chlamydia diagnoses across all states. To circumvent possible endogeneity, we use a large exogenous supply shock in the US methamphetamine market that occurred in May 1995 and a later shock stemming from the Methamphetamine Control Act, which went into effect in October 1997. While the supply shocks had large negative effects on methamphetamine use, we find no evidence that they decreased syphilis, gonorrhea, or chlamydia rates. Our results have broad implications for public policies designed to decrease sexually transmitted infection rates. Copyright © 2014 John Wiley & Sons, Ltd.