Heterogeneous population effects of an alcohol excise tax increase on sexually transmitted infections morbidity
ADDICTION
Authors: Staras, Stephanie A. S.; Livingston, Melvin D.; Christou, Alana M.; Jernigan, David H.; Wagenaar, Alexander C.
Abstract
Background and AimsAlcohol taxes reduce population-level excessive alcohol use and alcohol-related morbidity and mortality, yet little is known about the distribution of the effects of alcohol taxation across race/ethnicity and age subgroups. We examined the race/ethnicity- and age group-specific effects of an excise alcohol tax increase on a common and routinely collected alcohol-related morbidity indicator, sexually transmitted infections. MethodsWe used an interrupted time series design to examine the effect of a 2009 alcohol tax increase in Illinois, USA on new cases of two common sexually transmitted infections (chlamydia and gonorrhea) reported to the US National Notifiable Disease Surveillance System from January 2003 to December 2011 (n=108 repeated monthly observations). We estimated the effects of the tax increase on infection rates in the general population and within specific race/ethnicity and age subgroups using mixed models accounting for temporal trends and median income. ResultsFollowing the Illinois alcohol tax increase, state-wide rates of gonorrhea decreased 21% [95% confidence Interval (CI)=-25.7, -16.7] and chlamydia decreased 11% [95% CI=-17.8, -4.4], resulting in an estimated 3506 fewer gonorrhea infections and 5844 fewer chlamydia infections annually. The null hypothesis of homogenous effects by race/ethnicity and age was rejected (P<0.0001). Significant reductions were observed among non-Hispanic blacks: gonorrhea rates decreased 25.6% (95% CI=-30.0, -21.0) and chlamydia rates decreased 14.7% (95% CI=-20.9, -8.0). Among non-Hispanics, point estimates suggest decreases were highest among 25-29-year-olds. ConclusionsIncreased alcohol taxes appear to reduce sexually transmitted infections, especially among subpopulations with high disease burdens, such as non-Hispanic blacks.
Perceived stress and incident sexually transmitted infections in a prospective cohort
ANNALS OF EPIDEMIOLOGY
Authors: Turpin, Rodman; Brotman, Rebecca M.; Miller, Ryan S.; Klebanoff, Mark A.; He, Xin; Slopen, Natalie
Abstract
Purpose: Psychosocial stress has been associated with susceptibility to many infectious pathogens. We evaluated the association between perceived stress and incident sexually transmitted infections (Sits; Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis genital infections) in a prospective study of women. Stress may increase vulnerability to STIs by suppressing immune function and altering the protective vaginal microbiota. Methods: Using the 1999 Longitudinal Study of Vaginal Flora (n = 2439), a primarily African American cohort of women, we fitted Cox proportional hazards models to examine the association between perceived stress and incident STIs. We tested bacterial vaginosis (measured by Nugent Score) and sexual behaviors (condom use, number of partners, and partner concurrence) as mediators using VanderWeele's difference method. Results: Baseline perceived stress was associated with incident STIs both before and after adjusting for confounders (adjusted hazard ratio = 1.015; 95% confidence interval, 1.005-1.026). Nugent score and sexual behaviors significantly mediated 21% and 65% of this adjusted association, respectively, and 78% when included together in the adjusted model. Conclusions: This study advances understanding of the relationship between perceived stress and STIs and identifies high-risk sexual behaviors and development of bacterial vaginosis-both known risk factors for STIs-as mechanisms underlying this association. (C) 2019 Elsevier Inc. All rights reserved.