Effect of non-overlapping visual field defects on vision related quality of life in glaucoma

Purpose Glaucoma patients may be considered to have normal vision as long as each point of visual space is perceived by at least one eye, that is, with an intact binocular visual field. We aimed to investigate the effect of non-overlapping visual field (VF) defects on vision-related quality life (VR-QoL) in glaucoma. Methods We evaluated VR-QoL of glaucoma patients (n=269) and controls (n=113) using four different questionnaires (NEI-VFQ-25, NEI-VFQ neuro-ophthalmology supplement, GQL-15, and a luminance-specific questionnaire). We defined ‘differential VF’ (DVF) as a measure of location-specific differences in the VFs of both eyes. Within the group of glaucoma patients, we analysed the relationship between different aspects of VR-QoL and DVF using ordinal multiple regression analysis. Analyses were adjusted for age, gender, integrated VF (IVF; an estimate of the binocular VF from the monocular VFs), and higher visual acuity of both eyes, and corrected for multiple hypothesis testing. Results Glaucoma patients had a lower VR-QoL than controls. Within the glaucoma patients, DVF was significantly associated with general vision (odds ratio 0.69, 95% confidence interval 0.54-0.89), peripheral vision (0.68, 0.54-0.86), walking on uneven ground (0.73, 0.58-0.93), crossing the street (0.61, 0.46-0.83), seeing other road users coming from the side (0.67, 0.52-0.85), cycling during the day (0.64, 0.46-0.89) and seeing outside on a sunny day (0.73, 0.57-0.94). In general, IVF was a stronger predictor of VR-QoL than DVF. Conclusions Non-overlapping VF defects affect VR-QoL. Although IVF is strongly associated with VR-QoL, basing clinical decisions only on IVF leads to overlooking vision problems that patients may have.