Long-Term Health Risks Following Tuberculosis Diagnosis and Treatment
A large, population-based study in Brazil reveals a significantly elevated risk of mortality among individuals diagnosed with and treated for tuberculosis (TB) compared to those who have never had the disease. This increased risk extends for at least 14 years after diagnosis, even after successful treatment, and spans a range of causes beyond respiratory illness.
The Lasting Impact of TB: A Significant Mortality Risk
Researchers found that individuals diagnosed with TB experienced 15,168 more deaths per 100,000 persons over 14 years compared to TB-free participants with similar socioeconomic backgrounds. Even after completing treatment, a substantial excess mortality remained, with 8,206 more deaths per 100,000 persons. This highlights the enduring health consequences of TB, even when the infection is successfully cured.
Beyond the Lungs: Increased Risk Across Multiple Organ Systems
The increased mortality risk wasn’t limited to respiratory causes. The study identified elevated risks of death from cardiovascular disease, endocrine disorders, and cancer among TB survivors. This suggests that TB has systemic effects that can impact long-term health across various organ systems.
Respiratory Complications
An increased risk of respiratory mortality aligns with previous research, largely due to direct lung damage from TB, which can lead to recurrent pneumonia, chronic obstructive pulmonary disease, and bronchiectasis 1.
Cardiovascular Risks
The study complements existing epidemiological evidence demonstrating a link between TB and increased cardiovascular mortality, even in the long term 1.
Endocrine Disorders and Diabetes
Notably, deaths related to endocrine disorders were also elevated. This may reflect a bidirectional relationship between TB and diabetes mellitus. Diabetes can increase susceptibility to TB, whereas TB-related inflammation can worsen insulin resistance and increase the risk of diabetes-related mortality 1.
Cancer Risk
The study found an increased risk of cancer deaths, including cancers of the digestive organs, consistent with a growing body of evidence suggesting a long-term link between TB and cancer 1. Potential mechanisms include chronic systemic inflammation and shared lifestyle risk factors like smoking and alcohol use 1.
Social Factors and External Causes of Death
The research also revealed an increased risk of death from external causes, such as accidents or violence, in both diagnosed and treated TB cases. While the reasons for this are not fully understood, it may be linked to the social stigma associated with TB, which can lead to social isolation, economic hardship, and mental health issues 1. Even when comparing TB patients to household contacts with similar socioeconomic conditions, the risk of death from external causes remained elevated in the TB group.
The Necessitate for Long-Term Follow-Up Care
These findings underscore the need for a paradigm shift in TB care, moving beyond simply diagnosing and curing active disease to providing comprehensive, long-term follow-up. Integrating post-TB assessments – including lung function testing, cardiovascular risk screening, and cancer surveillance – into national guidelines is crucial. This will enable early detection and management of potential complications, improving the long-term health and well-being of TB survivors.
Regional Disparities in Brazil
Data from 2002 to 2019 indicate that the North region of Brazil consistently presented the highest standardized incidence and mortality rates for pulmonary tuberculosis for both sexes 2. Projections suggest an increase in death risk in the North, South, and Center-West regions 2. While Brazil as a whole shows decreasing trends in incidence and mortality, regional differences remain significant and require targeted interventions.
Brazil did not reach the MDG related to tuberculosis mortality, and substantial differences were observed among the regions, and regional differences should be taken into account when tuberculosis control measures are being planned 3.
1 Long-term risk of death after tuberculosis diagnosis and treatment
2 Incidence and mortality by pulmonary tuberculosis in Brazil: Trends and projections, 2002-2034
3 Tuberculosis in Brazil: one country, multiple realities