Association between preserved ratio impaired spirometry and postoperative pulmonary complications in patients undergoing lung cancer resection

Postoperative pulmonary complications (PPCs) are associated with adverse clinical outcomes and increased hospitalization-related costs. Preserved ratio impaired lung function (PRISm) is a lung function phenotype distinct from obstructive lung disease, and little is known about the effect of PRISm on PPCs. The aim of this study was to investigate the association between PRISm and PPCs in patients undergoing lung cancer resection.

This retrospective cohort study involved patients who underwent lung cancer resection in the thoracic surgery case database between January 2019 and June 2019 at Shanghai Pulmonary Hospital. Demographics, preoperative measurements of spirometry, operative characteristics, PPCs, and length of stay were assessed.

The incidence of PPCs in the three groups was 36.84% in the PRISm group, 23.39% in the normal spirometry group, and 51.57% in the COPD group. Using a variable-selection strategy (forced clinical confounders plus univariable screening at P < 0.20), patients with PRISm were 2.07 times more likely to develop a PPC compared with normal spirometry [95% confidence interval (95% CI): 1.21-3.55; p = 0.008], and the relationship was not statistically different between PRISm and COPD groups [odds ratio (OR) = 0.63, 95% CI: 0.38-1.04; p = 0.071]. In subgroup analyses, non-restrictive PRISm was not associated with a significantly increased risk of PPCs relative to restrictive PRISm (adjusted OR = 1.32, 95% CI: 0.59-2.95; p = 0.494).

Compared with normal spirometry, PRISm was independently associated with a higher risk of PPCs in patients undergoing lung cancer resection. Preoperative identification of PRISm may refine preoperative risk stratification. Candidate targeted strategies, such as preoperative pulmonary rehabilitation, lung-protective intraoperative ventilation, and intensified postoperative surveillance, warrant prospective evaluation. The risk did not differ significantly between PRISm subtypes, though this finding requires further validation.