Dear Editor

We read with interest the extended report by Hassell and colleagues [1] demonstrating the adverse effect of quality of life in mild visual impairment (<6/12) and worse. Their demonstration of the impact of Age Related Macular Degeneration (AMD) on quality of life indices is an important illustration of the difficulties experienced by the visually impaired.

We have reported a similar experience in West Glamorgan (Wales, United Kingdom) [2]. Our study comprised of 66 patients registered as blind/partially sighted (59.1% because of AMD). The demographic characteristics mirrored this study (mean age 81.33 (SD 9.87); 69.7% female). We utilised an alternative index to the Impact of Vision Impairment (IVI) questionnaire, the National Eye Institute Visual Function Questionnaire (NEI-VFQ 25) [3]. This has similar categories including general health, general vision, ocular pain, near activities, distance activities, social functioning, mental health, role difficulties, dependency, colour vision, peripheral vision.

Hassell et al demonstrated a statistically significant restriction in leisure and work, social and consumer interaction and household and personal care difficulties between those with a mild/moderate compared to the severely impaired group. This was our experience in the analogous categories of social functioning (NEI-VFQ score 36.49% for the blind vs. 50% for the partially sighted; p = 0.0005) and dependency (NEI-VFQ score 30.07% for the blind vs. 46.98% for the partially sighted; p = 0.0003). Furthermore, percentage scores in our study were less than 50% for all categories except general health, ocular pain and peripheral vision for the blind and partially sighted. Of the studies that have utilised the NEI-VFQ in order to determine the extent of visual function, none have previously demonstrated mean scores as low as our study (Brody et al 2001[4]; Klein et al 2001[5]). Hassell et al have therefore not only demonstrated a worse quality of life in the severely visually impaired (<6/60), but reinforce the important fact that all those with visual impairment experience difficulties.

A second interesting finding in their paper was the absence of correlation between duration of visual impairment and adaptation. We found that the NEI-VFQ scores for those living alone were better than for individuals living with someone for numerous categories including near vision activities (20.9% vs. 15.3%, p=0.03), distant vision activities (27.9% vs. 20.1%, p=0.056) and dependency (46.3 vs. 31.4%, p=0.004) (Williams GP, Pathak-Ray V and Austin MW 2001, Unpublished Data).

This may imply that living alone forces people to adapt. We interpreted this finding with caution however as a number of the people 'living with someone' resided in a nursing/residential home. This may have occurred as a result living alone causing difficulties with coping in the first instance.

Finally, their paper was undertaken before people had received low vision services. Depressingly, our study found that there was incomplete delivery of formal low visual aid assessment (n=44, 66%); of these 70% found them to be of use. We therefore agree with the authors that not only should there be consideration of referral to low visual services, but adequate delivery and support is required in order to for it to be effective.

Mr Geraint P Williams BSc, MRCOphth Mrs Vanita Pathak-Ray FRCS (Ed) Mr Michael W Austin FRCS, FRCOPhth

References

[1] Hassell JB, Lamoureux EL and Keefe JE. Impact of age related macular degeneration on quality of life. British Journal of Ophthalmology 2006;90:593-596

[2] Williams GP, Pathak-Ray V, Austin MW, Lloyd AP, Millngton IM and Bennett A. Quality of life and visual rehabilitation: an observational study of low vision in West Glamorgan. Eye 2006 Feb 3 [Epub ahead of print]

[3] Mangione CM, Lee PP, Gutierrez PR, Spritzer K, Berry S and Hays RD. Development of the 25-item National Eye Institute Visual Function Questionnaire. Archives of Ophthalmology, 2001. 119(7):1050-8.

[4] Brody BL, Gamst AC, Williams RA, Smith AR, Lau PW, Dolnak D et al. Depression, Visual Acuity, Comorbidity, and Disability Associated with Age-related Macular Degeneration. Ophthalmology 2001;108(10)1893- 1900

[5] Klein R, Moss SE, Klein BEK, Gutierrez P and Mangione CM. The NEI-VFQ-25 in People With Long Term Type-1 Diabetes Mellitus. Archives of Ophthalmology 2001;119:733-740.