Predictors of intraocular pressure response and survival after phacoemulsification for glaucomatous eyes in the IRIS registry (Intelligent Research in Sight)

This retrospective cohort study describes the real-world incidence and maintenance of clinically meaningful intraocular pressure (IOP) reduction ("response") following stand-alone phacoemulsification for 667,987 eyes with suspected or confirmed glaucoma in the IRIS Registry (Intelligent Research in Sight) from 1/1/2013-9/30/2019. Intraocular pressure responders had ≥ 20% IOP reduction in daily mean IOP from baseline on two consecutive postoperative visits. We declared failure if a responder no longer maintained ≥ 20% IOP reduction. The estimated IOP responder rate was 41.3% by Kaplan-Meier analysis. Multivariate analysis demonstrated relationships between IOP response and baseline IOP (hazard ratio (HR) (95% confidence interval)) 1.48 (1.48-1.49), per 3 mmHg, P < 0.0001), age (HR 1.14 (1.13-1.14), per 10 years, P < 0.0001), male sex (HR 1.13 (1.12-1.15), P < 0.0001), prostaglandin analogue (HR 0.88 (0.87-0.90), P < 0.0001), and Rho-kinase inhibitor use (HR 1.50 (1.32-1.70), P = 0.01). Fifty percent of IOP responders failed at a median time of 14.3 months. Multivariate analysis demonstrated relationships between failure and baseline IOP (HR 0.75 (0.75-0.76), per 3 mmHg, P < 0.0001), nitric oxide donating prostaglandin (HR 1.78 (1.46-2.18), P < 0.0001) and Rho-kinase inhibitor use (HR 1.73 (1.43-2.09), P < 0.0001). Clinicians may counsel glaucoma patients with risk factors on whether to anticipate an IOP response and its expected duration after stand-alone phacoemulsification.