Risk factors associated with development of pulmonary impairment after tuberculosis

Treatment of pulmonary tuberculosis (PTB) focuses on microbiological cure and radiological improvement. However, many patients develop pulmonary impairment after the completion of anti-tubercular therapy (ATT), which affects their quality of life (QoL).

To study the occurrence and severity of pulmonary impairment after tuberculosis (PIAT), risk factors associated with development of PIAT and QoL after development of PIAT.

146 eligible PTB patients, who completed their ATT during January 2013 to December 2013 at National Institute of TB and Respiratory Diseases (NITRD), New Delhi and peripheral centres were enrolled after informed consent and evaluated. PIAT was graded using spirometric parameters. Severity of dyspnoea was assessed using Borg scale and Medical Research Council (MRC) scale. QoL was assessed using Seattle's Obstructive Lung Diseases Questionnaire (SOLDQ).

74% (108) had PIAT. On univariate analysis, smoking, education, body mass index (BMI), duration of illness prior to diagnosis of TB and number of prior ATT courses taken were the significant risk factors associated with the development of PIAT. On multiple logistic regression, patients who had taken ATT more than once was the independent risk factor associated with PIAT. Severity of dyspnoea was increased on both Borg scale and MRC scale with the increase in impairment of lung function. QoL was lower in patients with severe impairment.

After bacteriological cure of TB after treatment, significant numbers of patients have poor lung function and poor QoL. There is need for prevention and management of such sequelae under national programme.