Risk factors and biomarkers for post-tuberculosis lung damage in a Chinese cohort of male smokers and non-smokers: protocol for a prospective observational study

Abstract

IntroductionPost-tuberculosis lung damage (PTLD) refers to the residual pulmonary impairment following the completion of antituberculosis (TB) therapy, characterised by persistent respiratory symptoms and abnormal pulmonary function. The risk factors and biomarkers for PTLD have been scarcely investigated. More importantly, whether and to what extent cigarette smoking is involved in PTLD remain to be known.Methods and analysisThis prospective observational study will enrol 400 male smoking or non-smoking patients aged 25–65 years, with newly confirmed active TB between 2022 and 2024, from the Department of Respiratory and Critical Care Medicine at Peking University Third Hospital and the Tuberculosis Department at Beijing Geriatric Hospital. Because females rarely smoke in China, we will enrol only males in this study. Demographic data, smoking history and amount, clinical symptoms, lung function, and chest CT findings will be prospectively collected. Respiratory questionnaires, lung function measurements and chest CT examinations will be performed immediately after, and 1 year, 2 years and 3 years after the completion of TB treatment. Peripheral blood samples will be obtained at baseline and at the end of anti-TB therapy, and a Luminex xMAP-based multiplex immunoassay will be used to measure inflammatory mediators and cytokines in serum. The collected data will be analysed to determine the incidence and factors/biomarkers of PTLD according to smoking status.Ethics and disseminationThe study was approved by the Ethics Committee of Peking University Third Hospital (approval number: (2022)271-03; approval date: 8 June 2022). The research results will be disseminated through scientific and medical conferences and will be published in an academic journal.Trial registration numberNCT04966052.

The obstructive phenotype of chronic posttuberculosis disease - is there a role for the occupational exposure?

“…Risk-factors for PTLD occurrence include multiple TB episodes of disease, delayed diagnosis and treatment, drug-resistant spectrum of Mycobacterium tuberculosis bacilli, exposure to smoking or occupational dust or particles, poverty, outdoor and indoor pollution [9]. This case reported by us is eloquent from the perspective of delayed diagnosis of PTB and delayed therapy, heavy exposure to smoking (63 pack-year), occupational exposure to iritative respiratory noxes, poverty and alcoholism.…”