Quality of Life in Patients With Age Related Macular Degeneration – A Conjoint Analysis Approach

Abstract

Abstract: : Purpose: To study the quality of life (QOL) of patients with age related macular degeneration (AMD). Methods: A group of 81 subjects attending the low vision and AMD clinic at the Princess Alexandra Eye Pavilion in Edinburgh were given a battery of tests which included visual function tests and QOL questionnaires. We defined AMD in the following severity categories: mild - either mild in both eyes OR mild in one eye and moderate in the other eye; moderate - mild in one and severe in the other OR moderate in both eyes; or severe - late dry or wet AMD in both eyes. In addition to the Quality of Life questionnaires, patients were given a conjoint analysis task to complete. The conjoint was to assess aspects of quality of life which are rarely addressed in conventional questionnaires (i.e., patient values and relative importance of different daily tasks). Results: Background data on the patients showed a mean age of 77 yrs (SD=6.8); mean binocular distance logmar of 0.53 (SD=.43); mean binocular near acuity of 0.7 (SD=0.44); mean binocular contrast sensitivity (Pelli Robson) of 1.17 (SD=0.4). Sixty percent of patients were classed as ‘severe'AMD, 28% of patients as ‘moderate' AMD, and 12% of patients as ‘mild' AMD. Results showed that the most significant changes in quality of life as reported through the questionnaires occurred at the transition between moderate and severe forms of the disease. The exception was emotionally relevant questions and patient confidence, which showed a decline between all three AMD states. In addition conjoint analysis showed that practical tasks associated with independence had highest priority - that is the order of perceived importance from a 5 attribute conjoint task was outdoor mobility, household chores, reading, recognising faces, and glare. This rank order was preserved in a shorter 3 attribute conjoint task given to patients with extremely poor vision. Conclusions: The most significant change in QOL occurred between moderate and severe forms of the disease. Patient concerns were mainly over mobility and household tasks, suggesting a priority for preserving an independent lifestyle.

Keywords: clinical (human) or epidemiologic studies: out • clinical (human) or epidemiologic studies: hea • clinical (human) or epidemiologic studies: tre