A Bayesian Approach to Understanding Sex Differences in Tuberculosis Disease Burden

Area of Science:

• Epidemiology
• Mathematical Modeling
• Public Health

Background:

• Globally, men exhibit a higher epidemiologic burden of tuberculosis (TB) compared to women.
• Potential factors contributing to this disparity include differences in disease incidence, treatment seeking, self-cure rates, and mortality from untreated TB.

Purpose of the Study:

• To investigate the key factors driving the higher tuberculosis burden observed in men.
• To quantify the duration of untreated disease in men and women using a mathematical model.

Main Methods:

• A simple, sex-stratified compartmental model was developed.
• A Bayesian approach was utilized to analyze data from smear-positive pulmonary tuberculosis cases in Vietnam (2006-2007) and Malawi (2013-2014).
• Model estimates were compared with country-specific prevalence and notification data.

Main Results:

• Model estimates aligned with observed sex-specific TB prevalence and notifications in both countries.
• Results confirmed higher TB incidence rates in men.
• Both sexes experienced significantly longer durations of untreated disease than previously estimated, with men's untreated disease duration being approximately one year longer than women's in both countries.

Conclusions:

• The substantial sex differences in tuberculosis burden are primarily attributed to men's higher disease incidence and longer untreated disease durations.
• Self-reports significantly underestimate the duration of untreated disease, indicating gaps in case-finding strategies.
• There is an urgent need to address gender-related barriers affecting men and to implement targeted screening programs for men.