Impact of age-related macular degeneration in patients with glaucoma: understanding the patients' perspective.
BACKGROUND
The aim of the study is to measure the impact of age-related macular degeneration on vision-related activity limitation and preference-based status for glaucoma patients.


METHODS
This was a cross-sectional study.


METHODS
Two-hundred glaucoma patients of whom 73 had age-related macular degeneration were included in the research.


METHODS
Sociodemographic information, visual field parameters and visual acuity were collected. Age-related macular degeneration was scored using the Age-Related Eye Disease Study system.


METHODS
The Rasch-analysed Glaucoma Activity Limitation-9 and the Visual Function Questionnaire Utility Index measured vision-related activity limitation and preference-based status, respectively. Regression models determined factors predictive of vision-related activity limitation and preference-based status. Differential item functioning compared Glaucoma Activity Limitation-9 item difficulty for those with and without age-related macular degeneration.


RESULTS
Mean age was 73.7 (±10.1) years. Lower better eye mean deviation (β: 1.42, 95% confidence interval: 1.24-1.63, P < 0.001) and age-related macular degeneration (β: 1.26 95% confidence interval: 1.10-1.44, P = 0.001) were independently associated with worse vision-related activity limitation. Worse eye visual acuity (β: 0.978, 95% confidence interval: 0.961-0.996, P = 0.018), high risk age-related macular degeneration (β: 0.981, 95% confidence interval: 0.965-0.998, P = 0.028) and severe glaucoma (β: 0.982, 95% confidence interval: 0.966-0.998, P = 0.032) were independently associated with worse preference-based status. Glaucoma patients with age-related macular degeneration found using stairs, walking on uneven ground and judging distances of foot to step/curb significantly more difficult than those without age-related macular degeneration.


CONCLUSIONS
Vision-related activity limitation and preference-based status are negatively impacted by severe glaucoma and age-related macular degeneration. Patients with both conditions perceive increased difficulty walking safely compared with patients with glaucoma alone.
Discipline of Ophthalmology, University of Sydney, Sydney, New South Wales, Australia.|Ophthalmology Department, Addenbrookes Hospital, Cambridge, UK.|Departments of Ophthalmology and Surgery, Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia.|Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.
Simon E
SE
Skalicky
Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.
Eva
E
Fenwick
Ophthalmology Department, Addenbrookes Hospital, Cambridge, UK.|Cambridge NIHR Biomedical Research Centre, University of Cambridge, Cambridge, UK.
Keith R
KR
Martin
Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Victoria, Australia.
Jonathan
J
Crowston
Discipline of Ophthalmology, University of Sydney, Sydney, New South Wales, Australia.|Eye Associates, Sydney, New South Wales, Australia.|Sydney Eye Hospital, Sydney, New South Wales, Australia.
Ivan
I
Goldberg
Discipline of Ophthalmology, University of Sydney, Sydney, New South Wales, Australia.|Sydney Eye Hospital, Sydney, New South Wales, Australia.
Peter
P
McCluskey
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D014792:Visual Acuity / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology*
Rasch analysis; activity limitation; age-related macular degeneration; glaucoma; utility value