Study of possible predictors associated with self-assessed visual function after cataract surgery

Abstract

Objective: To determine the preoperative or postoperative patient-related factors that make patients benefit more or less from cataract surgery.

Design: Multicenter, prospective, cross-sectional Swedish National Cataract Register study.

Participants: A total of 14 817 patients who underwent cataract surgery from 2000 to 2006 in 42 Swedish ophthalmology departments.

Methods: The patients completed the Catquest questionnaire before and 6 months postoperatively. The 9 questions in the revised Catquest-9SF were selected from the Catquest and recoded by Rasch analysis, which makes it possible to use parametric statistics when analyzing the study data. The change from preoperative to postoperative, the postoperative mean subjective visual function, and satisfaction with vision were assessed with multiple regression or logistic regression with dummy variables where appropriate, in relation to waiting time, age, preoperative and postoperative corrected distance visual acuity (CDVA), ocular comorbidity, a first- or second-eye surgery, gender, achieved postoperative refraction, correct sign biometry prediction error, and absolute biometry prediction error.

Main outcome measures: Three outcome measures from Catquest-9SF of patient self-assessed visual function after cataract surgery.

Results: Young age (P<0.001), low preoperative CDVA (P<0.001), high postoperative CDVA (P<0.001), no ocular comorbidity (P<0.001), and postoperative myopia (-2 to 0 diopters [D]) instead of hyperopia (>0 to +2 D; P<0.05) led to significantly greater improvement in subjective visual function and a better postoperative subjective visual function than the counterparts. Women (P<0.001) and patients who underwent a first-eye surgery (P<0.001) had greater improvement but lower postoperative subjective visual function (P<0.001) than men and patients who underwent a second-eye surgery. A correct sign biometry prediction error of plus instead of minus led to greater improvement in subjective visual function (P<0.01) but no difference in postoperative subjective visual function. The absolute biometry prediction error had no effect on the change in subjective visual function, the subjective mean visual function or satisfaction with vision.

Conclusions: Several patient preoperative and postoperative factors are related to the self-assessed benefit of cataract surgery. Age, preoperative and postoperative CDVAs, ocular comorbidity, a first- or second-eye surgery, gender, and achieved postoperative refraction were related to changes in subjective visual function, subjective visual function, and satisfaction with vision.