Risk factors associated with mortality in hypersensitivity pneumonitis: a meta-analysis

ABSTRACT

Background

Hypersensitivity pneumonitis (HP) related deaths have increased substantially in recent years. It is important to identify the risk factors of HP significantly associated with mortality to ensure close patient monitoring and assess disease progression.

Research design and methods

Extensive literature search was conducted in accordance with the PRISMA checklist. Literature search of PubMed, Embase, and Cochrane Library database between January 2009 and April 2021 using the terms ‘hypersensitivity pneumonitis’, ‘hazard ratio’, and ‘mortality’ identified 325 articles. A total of 22 independent original studies focusing on mortality of HP patients were assessed.

Results

This systematic review and meta-analysis suggests that increased age, male sex, honeycombing, and traction bronchiectasis patterns on high-resolution computed tomography (HRCT) images are the major mortality-related risk factors of patients with HP. In case of chronic HP, antigen exposure appeared to be an additional risk factor.

Conclusions

The clinico-radiological risk factors of mortality identified for HP will enable effective and close monitoring of patients, prognostication, and guide toward appropriate management decisions. However, association between the type of antigen and mortality remains to be explored.

KEYWORDS:

• Hazard ratio
• hypersensitivity pneumonitis
• mortality
• risk factor
• survival

Abbreviations

DLco	=	Diffusing capacity for carbon monoxide
DPLD	=	Diffuse parenchymal lung disease
FVC	=	Forced vital capacity
GGO	=	Ground glass opacity
HP	=	Hypersensitivity pneumonitis
HRCT	=	High-resolution computed tomography
IPF	=	Idiopathic pulmonary fibrosis
OR	=	Odds ratio

Acknowledgments

S Dasgupta and A Bhattacharya acknowledge the Ministry of Human Resource and Development, India, and Indian Institute of Technology Kharagpur for research fellowship.

Declaration of Interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

S Dasgupta has full access to all data used in the study and takes responsibility for the integrity and accuracy of the data. S Dasgupta, A Bhattacharya, and D Rajwade conducted literature search, extracted the results, performed the meta-analysis; and drafted the manuscript. S Roy Chowdhury and K Chaudhury revised the manuscript.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/17476348.2022.2100352

Additional information

Funding

This paper was not funded