Utility values and diabetic retinopathy

PURPOSE: To ascertain the utility values associated with diabetic retinopat hy and varying degrees of visual loss, METHODS: One hundred consecutive patients-with diabetic retinopathy and bes t-corrected visual acuity decreased to 20/40 or worse in at least one eye o ccurring primarily as a result of diabetic retinopathy were evaluated in a cross-sectional study, Utility values were ascertained in five groups using both the time trade-off and standard gamble methods: group 1 (best-correct ed visual acuity in the better eye of 20/20 to 20/25), group 2 (best-correc ted visual acuity in the better eye of 20/30 to 20/50), group 3 (best-corre cted visual acuity in the better eye of 20/60 to 20/100), group 4 (best cor rected visual acuity in the better eye of 20/200 to 20/400), and group 5 (b est-corrected visual acuity in the better eye of counting fingers to hand m otions). RESULTS: The mean utility value for the diabetic retinopathy group as a who le was 0.77 (SD = 0.21; 95% confidence interval [CI], 0.73 to 0.81) with th e rime trade-off method and 0.88 (SD = 0.20; 95% CI, 0.84 to 0.92) with the standard gamble method. Employing the time trade-off method correlated wit h the best-corrected visual acuity in the better eye, the mean utility resu lts were as follows: group 1 = 0.85 (95% CI, 0.75 to 0.95), group 2 = 0.78 (CI, 0.12 to 0.84), group 3 = 0.78 (CI, 0.67 to 0.89), group 4 = 0.64 (CI, 0.53 to 0.75), and group 5 = 0.59 (CI, 0.23 to 0.95), Thus, patients in gro up 1 (best-corrected visual acuity of 20/20 to 20/25 in the better eye) wer e willing to trade a mean of: 15% of their remaining years of life in retur n for perfect vision in each eye, whereas those in group 5 (best-corrected visual acuity of counting fingers to hand motions in the better eye) were w illing to trade a mean of 41% of their remaining years in return for perfec t vision in each eye. There was no significant difference in mean utility v alues between patients who had decreased visual acuity from diabetic retino pathy for 1 year or less compared with those with decreased acuity for more than 1 year. There was also no significant difference in mean utility valu es between those with a 12th grade education or less compared with those wi th more than a 12th grade education, CONCLUSION: Visual loss occurring secondary to dia betic retinopathy is ass ociated with a substantial decrease in patient utility value (and quality o f life), The utility value is directly dependent on the degree of visual lo ss associated with the disease, The length of time of visual loss and amoun t of formal education do not appear to affect the utility value. (Am J Opht halmol 1999;128: 324-330, (C) 1999 by Elsevier Science Inc. All rights rese rved.)