By Jill Stein
CHICAGO, IL -- June 24, 2007 -- A loss of at least 10 letters in visual acuity among diabetics with nonproliferative diabetic retinopathy decreases multiple quality-of-life measures, according to research described here at the American Diabetes Association 67th Scientific Sessions (ADA).
Matthew D. Rousculp, PhD, research consultant, Eli Lilly, Indianapolis, Indiana, United States, and associates examined the degree of change in health-related quality of life (HRQL) associated with changes in visual acuity among 684 patients with type 1 or 2 diabetes and moderate to severe nonproliferative diabetic retinopathy.
Participants in the analysis were enrolled in a 36-month, placebo-controlled, randomised trial of once-daily ruboxistaurin for vision loss in patients with diabetic retinopathy.
"Although the association between visual acuity and HRQL at one point in time has been well established, little is known about this link over time," Dr. Rousculp said in a presentation on June 24th.
In the present analysis, visual acuity was defined at each timepoint as each individual's best corrected vision as determined by the Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity chart score.
HRQL was evaluated using the 25-item Visual Function Questionnaire (VFQ-25) and the 36-question Short Form (SF-36) questionnaire.
Patients were classified into one of five groups based on their EDTRS change from baseline to month 18: improved by 10 or more letters; improved by 5 to 9 letters; no change (-4 to +4 letters); worsened by 5 to 9 letters; and worsened by 10 or more letters.
Results showed that the change in visual acuity was associated with a change in multiple domains of HRQL. Patients who had lost 10 letters on the ETDRS visual acuity chart (ie, a two-line loss) had significantly larger mean declines in nearly all VFQ-25 scales than any other group of patients, except for ocular pain.
While prior research has often defined vision loss as a loss of at least 15 letters, which is the equivalent of three lines on the ETDRS visual acuity chart, findings from the present study are in line with earlier research showing that even mild to moderate visual impairment has a "notable" impact on physical functioning.
Based on the results, Dr. Rousculp said that patients whose visual acuity loss has begun to affect their HRQL may benefit from early intervention aimed at bolstering the affected functional domains.
Eli Lilly provided funding for the study.
[Presentation title: The Link Between Visual Acuity and Health-Related Quality of Life Among Patients With Diabetic Retinopathy. Abstract 825-P]