Factors associated with elevated complication rates after partial-thickness or full-thickness glaucoma surgical procedures in the United States during 1994

Abstract

Objective The purpose of the study was to identify factors associated with an increased risk of complications after partial-thickness or full-thickness glaucoma surgery. Design A retrospective, cohort analysis. Participants A total of 24,206 Medicare patients who were older than 65 years of age and who were enrolled in Medicare in 1994 underwent partial-thickness or full-thickness glaucoma surgical procedures in 1994. Intervention The authors obtained data on all glaucoma surgery claims to the Health Care Finance Administration in 1994 and analyzed complication rates using hierarchical logistic regression, separately smoothing four sets of regression coefficients (state-level effects, systemic and ocular diagnoses, prior ocular surgeries, and concomitant ocular surgeries). Main outcome measure Patients were classified as having complications if their records showed at least one of the following occurrences after surgery: retinal detachment repair, endophthalmitis, scleral fistula revision—repair, or cyclodestruction. Results The risk of complications was greater for full-thickness procedures than for partial-thickness procedures (odds ratio [OR] = 1.51; 95% confidence interval [CI] = 1.07, 2.12). Compared to glaucoma surgeries performed without an additional intraocular procedure, glaucoma surgery with prior phacoemulsification (OR = 0.51; 95% CI = 0.35, 0.74) was associated with lower complication rates, as was glaucoma surgery with prior argon laser trabeculoplasty (OR = 0.62; 95% CI = 0.44, 0.88). A concomitant vitrectomy (OR = 1.86, 95% CI = 1.35, 2.56) was associated with greater odds of a complication. The mean follow-up of subjects was 184 days (standard deviation, ±107), whereas the mean time to a complication was 49 days (standard deviation, ±63). Conclusion The risk of an early postoperative complication after full-thickness procedures appears to be greater than that after partial-thickness procedures. Concomitant intraocular procedures performed in conjunction with glaucoma surgery, such as a vitrectomy, can substantially increase the risk of retinal detachment repair, endophthalmitis, scleral fistula revision—repair, and/or cyclodestruction.