TTO utility scores measure quality of life in patients with visual morbidity due to diabetic retinopathy or ARMD

Abstract

Purpose: To evaluate the utility scores in patients with varying degrees of visual morbidity due to diabetic retinopathy or ARMD.

Methods: Patients with vision < or =20/40 in one eye due to diabetic retinopathy or ARMD were enrolled. Utility scores were measured by the time trade-off (TTO) method after stratifying the patient population with visual impairment in the better eye (group 1, 20/20 to 20/40; group 2, 20/50 to 20/100; group 3, 20/200 to no light perception).

Results: Sub-group analysis revealed that subjects in group 1 were willing to give up a median of 1 year as compared to 3 years by the subjects in group 3 for perfect bilateral visual acuity (P<0.05). The median utility score was 0.94 for group 1, 0.96 for group 2 and 0.80 for group 3. While the utility scores for groups 1 and 2 were comparable (P>0.05), there was a significant difference in the utility scores between groups 1 and 3 and between groups 2 and 3 (P<0.05). There was no significant effect on the utility scores of age, educational level or prior ocular surgery.

Conclusion: Substantial visual loss secondary to diabetic retinopathy or ARMD is associated with a significant decrease in utility scores. However, TTO scores were not sensitive enough to demonstrate a difference between subjects with mild (group 1) and moderate (group 2) visual loss in the better eye secondary to diabetic retinopathy or ARMD.