Estimating the cost of visual impairment: initial results.

Abstract

Purpose: Vision loss can have a substantial human and economic impact on individuals and society that include disability, loss of productivity and reduction in quality of life. The purpose of this study was to estimate economic burden of visual impairment in Portugal.

Methods: A prevalence-based cost of illness approach was adopted to estimate costs of vision impairment. We estimated direct medical costs and indirect economic costs. Direct medical hospital costs were determined using a bottom up approach. For those meeting the inclusion criteria (visual acuity of 20/40 or 0.5decimal or worse in the better eye and/or visual field of less than 20deg) we estimated direct costs by collecting information from administrative records that included: physician’s office visits, emergency and outpatient visits. We developed a survey based in parts of the annotated cost questionnaire-HERU Discussion Paper N.03/01 (UK Working Party on Patient Costs) and the Service Receipt Inventory-European Version. Using the questionnaire that we developed, in face-to-face interviews, we collect direct medical expenditures supported by patients that included: costs with medical prescriptions, low vision aids and devices. With the same questionnaire we collected information for indirect costs calculations. Indirect costs were calculated by estimating the value of productivity losses including employment participation, absenteeism and caregiver costs.

Results: Results presented here correspond to 442 patients that met the inclusion criteria. The four main causes of visual impairment in this sample were Diabetic Retinopathy, Cataract, Glaucoma and Age-related macular degeneration. Direct medical hospital costs were accountable for 12% of total costs calculated. Patient expenditures represented 25% of expenses with visual impairment and indirect costs corresponded to 63% of the total. From this data we estimated that the average annual direct cost per patient with VI was 958 euro and average annual indirect cost was 1655 euro.

Conclusions: With the instruments and methodology that was adopted we were able quantify direct medical hospital costs as well as indirect costs of visual impairment. Results of this study show that more than half of the costs with VI are indirect. This highlights that particular attention should be given to costs that arise for individuals with vision loss.