Risk factors for intraoperative floppy iris syndrome: a meta-analysis

Abstract

Purpose: To evaluate risk factors (hypertension, diabetes mellitus, and current tamsulosin, alfuzosin, terazosin, or doxazosin use) for intraoperative floppy iris syndrome (IFIS) in patients undergoing phacoemulsification cataract surgery.

Design: Systematic review and meta-analysis of the literature.

Participants: Seventeen eligible studies (17 588 eyes) examining the association between IFIS and risk factors.

Methods: Pertinent publications were identified through a systematic search of PubMed. All references of relevant reviews and eligible articles were also screened. Language restrictions were not used, and data were extracted from each eligible study by 2 investigators working independently. For medications, 2 separate analyses were performed: an analysis using a dichotomous criterion (use/non-use of the examined agent) and an alternative analysis performing comparisons with patients not receiving any α(1)-blocker. The fixed-effects model (Mantel-Haenszel method) or the random-effects (DerSimonian Laird) model was appropriately used to calculate the pooled odds ratio (OR). Publication bias was appropriately assessed.

Main outcome measures: Pooled OR for the incidence of IFIS.

Results: The pooled OR for IFIS after tamsulosin use was approximately 40-fold greater (or 16.5 at the alternative analysis) than that after alfuzosin use, that is, the second α(1)-blocker in order of effect size. Alfuzosin and terazosin were also associated with IFIS with comparable ORs; the effect of doxazosin reached formal statistical significance at the alternative analysis. Intraoperative floppy iris syndrome was positively associated with hypertension (pooled OR = 2.2, 95% confidence interval [CI], 1.2-4.2, fixed effects) but not with diabetes mellitus (pooled OR = 1.3, 95% CI, 0.7-2.2, fixed effects).

Conclusions: This meta-analysis has highlighted a hierarchy concerning the role of α(1)-blockers in IFIS, indicating an extremely sizeable effect size of tamsulosin; this may entail important physiologic implications. Alfuzosin, terazosin, and doxazosin presented with comparable effect sizes. Hypertension, but not diabetes mellitus, emerged as a risk factor for IFIS.