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EW NEWS & OPINION 11 systemic α1-antagonists to report this medication history prior to having any eye surgery. The newly issued educational statement states, "Patients with symptomatic cataracts may wish to consider cataract surgery prior to initiating non-emergent α1-an- tagonist therapy. Because tamsulosin is associated with the highest risk of IFIS, patients with cataracts may wish to consider a non-selective α1-antagonist as initial treatment." We have communicated with the American Academy of Family Physicians, the American College of Physicians, and the American Urological Association who will each help to disseminate this information to their respective memberships. In addition, this document is a concise, referenced summary that ophthalmologists can share with prescribing doctors in their communities on an individual basis. It can be downloaded from the ASCRS website, www.ascrs.org. EW References 1. Chang DF, Braga-Mele R, Mamalis N, et al. ASCRS white paper: clinical review of intraop- erative floppy-iris syndrome. J Cataract Refract Surg 2008;34:2153–2162. 2. Chatziralli IP, Sergentanis TN. Risk factors for intraoperative floppy iris syndrome: A meta-analysis. Ophthalmology 2011; 118:730–735. 3. Palea S, Chang DF, Rekik M, et al. Compara- tive effect of alfuzosin and tamsulosin on the contractile response of isolated rabbit prosta- tic and iris dilator smooth muscles. Possible model for intraoperative floppy iris syndrome. J Cataract Refract Surg 2008; 34: 489–496. 4. Chang DF, Braga-Mele R, Mamalis N, et al. Clinical experience with intraoperative floppy- iris syndrome. Results of the 2008 ASCRS member survey. J Cataract Refract Surg 2008; 34:1201–1209. 5. Roehrborn, CG, Siami P, Barkin J, et al. The effects of combination therapy with dutas- teride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hy- perplasia: 4-year results from the CombAT study. Eur. Urol. 2010; 57:123–131. New continued from page 3 ASCRS and AAO educational update statement I n 2005 the U.S. Food and Drug Administration issued a new label warning about the association of α1-antagonists and intraoperative floppy iris syndrome (IFIS). Characterized by sudden intra- operative iris prolapse and pupil constriction, IFIS increases both the difficulty and the risk of cataract surgery. 1 Some complications of IFIS have been sight threatening, including retinal detachment, lost lens fragments, endophthalmitis, and severe iris defects associated with permanent pupil deformity, glare, and photophobia. 1-3 Tamsulosin is the most commonly prescribed α1-antagonist for benign prostate hyperplasia (BPH) in North America. Until the approval of silodosin, tamsulosin was the only systemic α1-antagonist that is selective for the α1-A receptor subtype that predominates in the prostate. Because vascular smooth muscle receptors are α1-B, the theoretical advantage of such receptor subtype selectivity is reduced risk of postural hypotension. Although initial blood pressure monitoring may be recommended when prescribing older non-selective α1-antagonists, such as terazosin and doxazosin, another non-selective α1-antagonist, alfuzosin, rarely causes postural hypotension and is associated with fewer cardiovascular adverse events. 4-6 It is well recognized that simply discontinuing oral α1-antagonists does not prevent IFIS. 1 Studies of rabbit and human cadaver eyes have shown that tamsulosin is associated with atrophy of the iris dila- tor smooth muscle and that this may be due to con- centration of the drug in iris pigment granules. 7,8 In 2008, the American Society of Cataract & Refractive Surgery (ASCRS) and the American Academy of Ophthalmology (AAO) jointly issued an educational update advisory on IFIS asking prescribing physicians to consider involving the cataract surgeon prior to initially prescribing non-emergent, chronic α1-antag- onists in patients with known cataracts. Prescribing physicians were also asked to encourage patients to report any prior or current history of α1-antagonist use to their ophthalmic surgeon prior to undergoing any eye surgery. Since the 2008 advisory statement, additional evidence has emerged showing that severe IFIS is more likely to occur with tamsulosin compared to non-selective α1-antagonists. A 2011 meta-analysis of 17 published studies found that tamsulosin had a 40-fold higher pooled odds ratio for IFIS compared to alfuzosin and terazosin. 9 A subsequent prospective, masked single surgeon study found severe IFIS more commonly with tamsulosin compared to non-selec- tive α1-antagonists as a group. 10 Finally, a newly published multicenter prospective study found that severe IFIS was statistically more likely with tamsu- losin than alfuzosin. 11 This was the first prospective, masked, and controlled study to specifically compare two α1-antagonists with a low reported incidence of cardiovascular adverse events. In a 2008 survey, nearly two-thirds of ophthalmologists said that if they themselves had a mildly symptomatic cataract they would either avoid tamsulosin or have their cataract removed first. 12 A newly published survey of primary care physi- cians from the University of California, San Francisco showed that only 35% were aware that α1-antago- nists can cause cataract surgical complications; only half (17%) factored this into treatment considera- tions. 13 Less than 10% inquire about a history of cataract prior to initiating α1-antagonist treatment, and only 31% regularly advise patients to inform their ophthalmologist about taking these drugs. Most respondents (96%) desired more information on this topic. We are issuing this updated educational state- ment for prescribing physicians based on these two newly published reports. Patients with symptomatic cataracts may wish to consider cataract surgery prior to initiating non-emergent α1-antagonist therapy. Because tamsulosin is associated with the highest risk of IFIS, patients with cataracts may wish to consider a non-selective α1-antagonist as initial treatment. References 1. Chang DF, Braga-Mele R, Mamalis N, et al. ASCRS white paper: clinical review of intraoperative floppy-iris syndrome. J Cataract Refract Surg 2008;34:2153–2162. 2. Bell CM, Hatch WW, Fischer HD, et al. Association between tamsulosin and serious ophthalmic adverse events in older men following cataract surgery. JAMA 2009;301(19):1991–1996. 3. Chang DF. Floppy Iris Syndrome: Why BPH can complicate cataract surgery. Am Fam Physician 2009;79:1051, 1055–1056. 4. McVary KT, Roehrborn CG, Avins AL, et al. Update on AUA guideline on the management of benign prostatic hyperplasia. J Urol 2011;185:1793–1803. 5. Buzelin JM, Delauche-Cavallier MD, Roth S, et al. Clinical uroselectivity: evidence from patients treated with slow-release alfuzosin for symptomatic benign prostatic obstruction. Br Journal Urol 1997;79:898–906. 6. Roehrborn CG. Alfuzosin: overview of pharmacokinetics, safety, and efficacy of a clinically uroselective alpha-blocker. Urology 2001;58:55–63. 7. Santaella RM, Destafeno JJ, Stinnett SS, et al. The effect of alpha1-adrenergic receptor antagonist tamsulosin (Flomax) on iris dilator smooth muscle anatomy. Ophthalmology 2010;117:1743– 1749. 8. Goseki T, Ishikawa H, Ogasawara S, et al. Effects of tamsulosin and silodisin on isolated albina and pigmented rabbit iris dilators – Possible mechanism of IFIS. J Cataract Refract Surg 2012;38: 1643–1649. 9. Chatziralli IP, Sergentanis TN. Risk factors for intraoperative floppy iris syndrome: A meta-analysis. Ophthalmology 2011;118:730–735. 10. Casuccio A, Cillino G, Pavone C, et al. Pharmacologic pupil dilation as a predictive test for the risk of intraoperative floppy-iris syndrome. J Cataract Refract Surg 2011;37:1447–1454. 11. Chang DF, Campbell JR, Colin J, Schweitzer C. Prospective masked comparison of intraoperative floppy iris syndrome severity with tamsulosin versus alfuzosin. Ophthalmology 2014;121: 829–834. 12. Chang DF, Braga-Mele R, Mamalis N, et al., for the ASCRS Cataract Clinical Committee. Clinical experience with intraoperative floppy-iris syndrome. Results of the 2008 ASCRS member survey. J Cataract Refract Surg. 2008;34:1201–1209. 13. Doss EL, Potter MB, Chang DF. Primary care physicians still lack awareness of IFIS. J Cataract Refract Surg 2014;40:685–686. Intraoperative floppy iris syndrome (IFIS) associated with systemic alpha 1-antagonists April 2014

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