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

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.

Systematic review and meta-analysis of the literature.

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

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.

Pooled OR for the incidence of IFIS.

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).

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.