Utility Values in Singapore Chinese Adults With Primary Open-Angle and Primary Angle-Closure Glaucoma

Abstract

To evaluate utility values in Chinese glaucoma patients. Singapore Chinese residents (n = 213) with primary open-angle glaucoma or primary angle-closure glaucoma were recruited from a single tertiary ophthalmic center. Standard face-to-face interviews were conducted to ask about utility values (time trade-off and standard gamble for both death and blindness). Ocular information, including current visual acuity, intraocular pressure, visual field defect, and cup-disc ratio were also obtained. The mean time trade-off utility value was 0.88 (95% confidence interval 0.85, 0.91), and standard gamble for death and blindness were 0.94 (95% confidence interval 0.93, 0.96) and 0.95 (95% confidence interval 0.93, 0.97), respectively. Only 35.7% of patients were willing to trade time, and 34.3% willing to risk blindness in return for perfect vision. Both primary angle-closure glaucoma and primary open-angle glaucoma patients had similar utility values. After adjusting for age, gender, language spoken, educational level, and diagnosis, patients with better eye visual field PSD > 10 were 2.52 times (95% confidence interval 1.13, 5.61) more willing to trade time. In a multivariate model, the odds ratio of willingness to risk blindness for a complete hypothetical glaucoma cure was 9.88 (95% confidence interval 1.65, 59.23) for patients who had only visited an ophthalmologist 15 years or more ago, and 0.53 (95% confidence interval 0.27, 1.02) for patients who had previous trabeculectomy. Most Chinese glaucoma patients in Singapore are not willing to trade time or risk blindness. Patients with worse visual fields in the better-seeing eye are more willing to trade time; whereas patients who have not seen an ophthalmologist for at least 15 years or who had no history of a previous trabeculectomy are more willing to risk blindness.