Persistent chronic respiratory symptoms despite TB cure is poorly correlated with lung function

Area of Science:

• Pulmonology
• Infectious Diseases
• Public Health

Background:

• Persistent respiratory symptoms and lung function deficits are common sequelae following tuberculosis (TB) treatment.
• Post-TB lung disease (PTLD) represents a significant, yet often underdiagnosed, health burden in affected individuals.

Purpose of the Study:

• To quantify the burden of PTLD in adults who completed TB treatment in high-incidence communities.
• To investigate associations between respiratory symptoms, lung function impairment, and functional capacity.

Main Methods:

• Cross-sectional survey of 145 adults in Cape Town, South Africa, 1-5 years post-TB treatment.
• Utilized questionnaires, spirometry to assess lung function (airflow obstruction, forced vital capacity [FVC]), and the 6-minute walking distance (6MWD) test.
• Multivariable analyses assessed factors associated with PTLD outcomes.

Main Results:

• High prevalence of airflow obstruction (38%) and low FVC (58%) was observed.
• Respiratory symptoms were common, including chronic cough (19%), wheeze (42%), and dyspnea (25%).
• Poor correlation existed between spirometric measures (FVC, obstruction) and 6MWD; low body mass index was consistently associated with adverse outcomes.

Conclusions:

• A substantial burden of symptoms and physiological impairment exists in individuals after TB treatment.
• The poor correlation between objective measures highlights gaps in understanding and managing PTLD.
• Underdiagnosis and undertreatment of respiratory disease were evident, with only 13% having a diagnosis and 11% receiving inhalers.