Pulmonary tuberculosis (TB) can affect lung function, but
studies regarding long-term follow-up in patients with no sequelae on chest
X-ray (CXR) have not been performed. We evaluated lung functional impairment
and persistent respiratory symptoms in those with prior pulmonary TB and those
with prior pulmonary TB with no residual sequelae on CXR, and determined risk
factors for airflow obstruction.
We used data from adults aged ≥ 40 years from the annual
Korean National Health and Nutrition Examination Surveys conducted between 2008
and 2012. P values for comparisons were adjusted for
age, sex, and smoking status.
In total of 14,967 adults, 822 subjects (5.5%) had diagnosed
and treated pulmonary TB (mean 29.0 years ago). The FVC% (84.9 vs. 92.6), FEV1% (83.4 vs. 92.4), and FEV1/FVC% (73.4 vs. 77.9) were significantly
decreased in subjects with prior pulmonary TB compared to those without (p < 0.001, each). In 12,885 subjects with
no sequalae on CXR, those with prior pulmonary TB (296, 2.3%) had significantly
lower FEV1% (90.9 vs. 93.4, p = 0.001) and FEV1/FVC%
(76.6 vs. 78.4, p < 0.001) than those without. Subjects with
prior pulmonary TB as well as subjects with no sequalae on CXR were more likely
to experience cough and physical activity limitations due to pulmonary symptoms
than those without prior pulmonary TB (p < 0.001, each). In total subjects, prior
pulmonary TB (OR, 2.314; 95% CI, 1.922–2.785), along with age, male, asthma,
and smoking mount was risk factor for airflow obstruction. In subjects with
prior pulmonary tuberculosis, inactive TB lesion on chest x-ray (OR, 2.300; 95%
CI, 1.606–3.294) were risk factors of airflow obstruction.
In addition to subjects with inactive TB lesion on CXR,
subjects with no sequelae on CXR can show impaired pulmonary function and
respiratory symptoms. Prior TB is a risk factor for airflow obstruction and
that the risk is more important when they have inactive lesions on chest X-ray.
Hence, the patients with treated TB should need to have regular follow-up of
lung function and stop smoking for early detection and prevention of the
chronic airway disease.
Below: Lung functions according to the presence of prior pulmonary tuberculosis.
(A) In all study subjects; (B) In subjects with normal chest X-rays. FVC: forced vital capacity; FEV1: forced expiratory volume in 1 second.
Below: Respiratory symptoms according to the presence of prior pulmonary tuberculosis.
(A) In all study subjects; (B) In subjects with normal chest X-rays. pvalues were adjusted for age, sex, and smoking status.
By: Jae-Woo Jung, Jae-Chol Choi, Jong-Wook Shin, Jae-Yeol Kim,
Byoung-Whui Choi, In-Won Park, Department of Internal medicine,
Chung-Ang University College of Medicine, Seoul, Korea