Association of preserved ratio impaired spirometry with mortality and cardiovascular diseases: a systematic review and meta-analysis

Abstract Background Preserved ratio impaired spirometry (PRISm) is a type of abnormal lung function. PRISm and mortality have been explored in several studies, but a comprehensive evaluation of the associations is limited. The current study aims to conduct a systematic review and meta-analysis in order to investigate the mortality and cardiovascular diseases in patients with PRISm. Methods PubMed, Embase, and Web of Science databases, as well as gray literature sources, were searched for relevant studies published up to 7 September 2023 without language restrictions. This review included all published observational cohort studies that investigated the association of PRISm with mortality in the general population, as well as subgroup analyses in smokers and pre-bronchodilation spirometry studies. The outcomes of interest were all-cause mortality, cardiovascular mortality, and respiratory-related mortality. The Newcastle–Ottawa scale assessed study quality. Sensitivity and subgroup analyses explored heterogeneity and robustness. Publication bias was assessed with Egger’s and Begg’s tests. Results Overall, eight studies were included in this meta-analysis. The pooled HR was 1.60 (95% CI , 1.48–1.74) for all-cause mortality, 1.68 (95% CI , 1.46–1.94) for CVD mortality, and 3.09 (95% CI , 1.42–6.71) for respiratory-related mortality in PRISm group compared to normal group. In the subgroup analysis, participants with PRISm had a higher effect ( HR , 2.11; 95% CI , 1.74–2.54) on all-cause mortality among smokers relative to participants with normal spirometry. Furthermore, the association between PRISm and mortality risk was consistent across several sensitivity analyses. Conclusions People with PRISm were associated with an increased risk of all-cause mortality, CVD mortality, and respiratory-related mortality as compared to those with normal lung function in the general population. Systematic review registration PROSPERO CRD42023426872.