Abstract
Purpose :
Keratoconus results in significantly impaired quality of life in affected individuals. We performed a prospective, observational clinical study to examine the relationship between keratoconus disease indicators and vision-related quality of life (V-QOL) in keratoconic patients.
Methods :
Data on 108 keratoconic patients (mean age 31.2 years, 68% male) was collected via a web-based keratoconus registry from a tertiary eye hospital and 2 corneal subspecialty practices (January 2015-June 2017). V-QOL was evaluated using the impact of Vision Impairment Questionaire (IVI) at study enrolment. Parameters analysed included visual acuity (VA), maximum simulated (Kmax) and steep (K2) keratometry, and pachymetry for each eye. Rasch analysis was used to transform the IVI responses into interval-level measures comprising reading, mobility and emotional well-being subscales.
Results :
Univariate analysis demonstrated a statistically significant decline in reading, mobility and emotional well-being logits between mild (n=37), moderate (n=41) and severe (n=29) keratoconus. Reading (r=0.51; 95% CI, 0.35-0.64; p <0.001) and mobility (r=0.55; 95% CI, 0.41-0.67; p <0.001) scores were significantly associated with VA in the better eye. Other significant associations included reading (r=-0.35; 95% CI, -0.51- -0.17; p=0.016) and mobility (r=-0.44; 95% CI, -0.58- -0.27; p=0.002) and Kmax in the better eye. VA in the worse eye was significantly negatively correlated with all 3 subscales.
Conclusions :
Lower V-QOL assessed with the IVI in keratoconus was associated with VA and Kmax in the better eye, and VA in the worse eye. Rasch analysis revealed the validity of the IVI to assess V-QOL in keratoconus using reading, mobility and emotional well-being subscales.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.