Related Experiment Video

Updated: Jan 24, 2026

Inverse Probability of Treatment Weighting Propensity Score using the Military Health System Data Repository and National Death Index
06:55

Inverse Probability of Treatment Weighting Propensity Score using the Military Health System Data Repository and National Death Index

Published on: January 8, 2020

15.1K

Differences in sexually transmitted infection risk comparing preexposure prophylaxis users and propensity score

Michalina A Montaño1, Julia C Dombrowski2,3, Sayan Dasgupta4

  • 1Department of Epidemiology.

AIDS (London, England)
|June 1, 2019
PubMed
Abstract

Insights

Men who have sex with men (MSM) using pre-exposure prophylaxis (PrEP) had higher rates of bacterial sexually transmitted infections (STIs) and faster time to symptomatic STIs compared to those not on PrEP.

Area of Science:

  • Public Health
  • Epidemiology
  • Infectious Diseases

Background:

  • Pre-exposure prophylaxis (PrEP) is a key HIV prevention strategy for men who have sex with men (MSM).
  • Understanding the impact of PrEP on other sexually transmitted infections (STIs) is crucial for comprehensive sexual health management.

Purpose of the Study:

  • To investigate whether MSM utilizing PrEP have an increased risk of bacterial STIs compared to MSM not using PrEP.
  • To analyze the incidence and time to symptomatic STIs among PrEP users and non-users.

Main Methods:

  • Secondary analysis of longitudinal STI data from MSM attending a Seattle STD Clinic (2011-2017).
  • Propensity score matching was used to compare PrEP users with a historical cohort of non-users.
  • Incidence of chlamydia, gonorrhea, early syphilis, and time to first symptomatic STI were compared.

Main Results:

  • The study included 365 PrEP users and 730 matched non-users.
  • PrEP users showed significantly higher adjusted incidence rate ratios for chlamydia (3.2), gonorrhea (2.8), and early syphilis (2.9) compared to non-users.
  • Time to first symptomatic STI was shorter for PrEP users (120 days) than for non-users (185 days).

Conclusions:

  • MSM using PrEP experienced a higher incidence of STIs and a quicker onset of symptomatic STIs.
  • The findings suggest PrEP use may be associated with increased STI rates among MSM, necessitating integrated prevention strategies.

More Related Videos

Fabrication and Characterization of Griffithsin-modified Fiber Scaffolds for Prevention of Sexually Transmitted Infections12:21

Fabrication and Characterization of Griffithsin-modified Fiber Scaffolds for Prevention of Sexually Transmitted Infections

Published on: October 31, 2017

7.9K
Induction and Clinical Scoring of Chronic-Relapsing Experimental Autoimmune Encephalomyelitis26:48

Induction and Clinical Scoring of Chronic-Relapsing Experimental Autoimmune Encephalomyelitis

Published on: July 4, 2007

18.7K

Related Concept Videos

Sexually Transmitted Infections01:26

Sexually Transmitted Infections

Sexually transmitted infections (STIs) are diseases transmitted primarily through unsafe sexual interactions. Bacteria, viruses, or parasites cause them and can result in severe health complications if untreated.ChlamydiaThe bacterium Chlamydia trachomatis is responsible for the disease Chlamydia, the most common STI in the United States. This peculiar pathogen requires human cells to reproduce, residing intracellularly. The initial infection often goes unnoticed because it typically does not...
958
Factors Affecting the Risk of Infection01:26

Factors Affecting the Risk of Infection

The hosts' susceptibility to infection depends on several factors. The integrity of the skin and mucous membranes helps protect the body against microbial attacks. When the skin is altered, the chance of infection, limb loss, and even death increases.
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin...
13.3K
Sign Test for Matched Pairs01:17

Sign Test for Matched Pairs

The sign test for matched pairs offers a robust method for comparing two paired samples, often for the effects of an intervention in one of them. This method is very useful in situations where the underlying distribution of the data is unknown. The test compares two related samples—often pre- and post-treatment measurements on the same subjects—to determine if there are significant differences in their median values.
To conduct the sign test, we first calculate the differences in...
392
Endocarditis II: Clinical Features of Infective Endocarditis01:25

Endocarditis II: Clinical Features of Infective Endocarditis

Endocarditis can present various clinical features depending on the causative organism and the patient's underlying health conditions. Initially, the clinical features of infective endocarditis develop gradually, presenting with nonspecific symptoms that can be easily mistaken for other illnesses.General SymptomsEarly symptoms of infective endocarditis are fever, chills, weakness, malaise, fatigue, and weight loss. These symptoms reflect the systemic nature of the infection and the body's...
454
Introduction to z Scores01:06

Introduction to z Scores

A z score (or standardized value) is measured in units of the standard deviation. It tells you how many standard deviations the value x is above (to the right of) or below (to the left of) the mean, μ. Values of x that are larger than the mean have positive z scores, and values of x that are smaller than the mean have negative z scores. If x equals the mean, then x has a zero z score. It is important to note that the mean of the z scores is zero, and the standard deviation is one.
z scores...
11.0K
Introduction to z Scores01:05

Introduction to z Scores

A z score (or standardized value) is measured in units of the standard deviation. It indicates how many standard deviations the value x is above (to the right of) or below (to the left of) the mean, μ. Values of x that are larger than the mean have positive z scores, and values of x that are smaller than the mean have negative z scores. If x equals the mean, then x has a zero z score. It is important to note that the mean of the z scores is zero, and the standard deviation is one.
z scores...
1.2K