Intraocular Pressure Spike Following Stand-Alone Phacoemulsification in the IRIS® Registry (Intelligent Research in Sight)

Purpose: To evaluate risk factors for intraocular pressure (IOP) spike after cataract surgery using the IRIS (R) Registry (Intelligent Research in Sight).<br /> Design: Retrospective clinical cohort study.<br /> Participants: Adults with IRIS Registry data who underwent stand-alone phacoemulsification from January 1, 2013, through September 30, 2019.<br /> Methods: Intraocular pressure spike was defined as postoperative IOP of > 30 mmHg and > 10 mmHg from the baseline within the first postoperative week. Odds ratios (ORs) for demographic and clinical characteristics were calculated with univariable and multivariable logistic regression analyses.<br /> Main Outcome Measures: Incidence and OR of IOP spike.<br /> Results: We analyzed data from 1 191 034 eyes (patient mean age, 71.3 years; 61.2% female sex; and 24.8% with glaucoma). An IOP spike occurred in 3.7% of all eyes, 5.2% of eyes with glaucoma, and 3.2% of eyes without glaucoma (P<0.0001). Multivariable analyses of all eyes indicated a greater risk of IOP spike with higher baseline IOP (OR, 1.57 per 3 mmHg), male sex (OR, 1.79), glaucoma (OR, 1.20), Black race (OR, 1.39 vs. Asian and 1.21 vs. Hispanic), older age (OR, 1.07 per 10 years), and complex surgery coding (OR, 1.22; all P < 0.0001). Diabetes (OR, 0.90) and aphakia after surgery (OR, 0.60) seemed to be protective against IOP spike (both P< 0.0001). Compared with glaucoma suspects, ocular hypertension (OR, 1.55), pigmentary glaucoma (OR, 1.56), and pseudoexfoliative glaucoma (OR, 1.52) showed a greater risk of IOP spike and normal-tension glaucoma (OR, 0.55), suspected primary angle closure (PAC; OR, 0.67), and PAC glaucoma (OR, 0.81) showed less risk (all P < 0.0001). Using more baseline glaucoma medications was associated with IOP spike (OR, 1.18 per medication), whereas topical B-blocker use (OR, 0.68) was protective (both P < 0.0001).<br /> Conclusions: Higher baseline IOP, male sex, glaucoma, Black race, older age, and complex cataract coding were associated with early postoperative IOP spike, whereas diabetes and postoperative aphakia were protective against a spike after stand-alone phacoemulsification. Glaucomatous eyes demonstrated different risk profiles dependent on glaucoma subtype. The findings may help surgeons to stratify and mitigate the risk of IOP spike after cataract surgery.<br /> Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. Ophthalmology 2024;131:780-789 (c) 2024 by the American Academy of Ophthalmology