Smoking as a risk factor of invasive fungal disease: Systematic review and meta-analysis

To investigate the association between smoking and invasive fungal disease (IFD), we searched MEDLINE and Web of Science for studies published until September 2018. Two authors independently performed study selection and data extraction. Relative risks (RRs) were pooled using random-effects meta-analysis. We included 25 studies (18,171 participants; 2,527 IFD cases). The meta-analysis showed an increased risk of IFD in smokers (RR 1.41 [95%CI 1.09-1.81]; P = 0.008). The risk of IFD was higher in retrospective than in prospective studies (RR 1.93 [1.28-2.92] vs. 1.02 [0.78-1.34]; P = 0.04), in studies with multivariate adjustment compared to studies with univariate analysis (RR 2.15 [1.27-3.64] vs. 1.15 [0.88-1.51]; P = 0.06), and in studies published after 2002 (RR 2.08 [1.37-3.15] vs. 0.95 [0.75-1.22]; P = 0.008); other subgroup characteristics did not significantly influence the association in meta-regression. Smoking cessation strategies should be implemented, especially in patients who are already at risk for IFD.