American Board of Family Medicine (ABFM) Practice Exam

Which of these is NOT a risk factor for the progression from latent tuberculosis to active disease?

1. Smoking

2. HIV infection

3. Chronic lung disease

4. Living in a rural area

The correct answer is: Living in a rural area

The progression from latent tuberculosis (TB) to active disease is influenced by various risk factors that compromise an individual's immune system or overall health. Among the options provided, living in a rural area does not inherently increase the risk of progression from latent TB to active disease. Risk factors such as smoking, HIV infection, and chronic lung disease have direct correlations with the progression of TB. Smoking compromises lung function and immune response, while HIV infection significantly weakens the immune system, making individuals more vulnerable to infections, including TB. Chronic lung diseases can also lead to altered lung function and increased susceptibility to respiratory infections, thereby facilitating the reactivation of latent TB. Conversely, residing in a rural area is not directly associated with an increased risk of progression from latent to active TB. While there may be other socio-economic factors or healthcare access issues that can impact TB prevalence in certain areas, simply living in a rural setting does not pose a specific risk for the disease’s progression. Thus, it is the only option that does not align with the established risk factors for the transition from latent tuberculosis to active disease.