You were asked to consider the following case:
A 76-year-old female patient is seeing you for an annual eye examination. She has already been diagnosed with dry age-related macular degeneration in both eyes and has been discharged from hospital with the advice to have annual eye examinations in community practice. .
Best corrected acuity: R 6/7.5 L 6/36
Her right eye shows extensive intermediate drusen and early nucleosclerotic cataract and in her left pseudophakic eye there is extensive subfoveal geographic atrophy.
She is happy with her overall level of vision. She has no significant general health concerns and is not taking any current prescription medicines.
She has read that ‘there may be some vitamin tablets that might help improve her vision.’
What advice regarding nutrition might you give to this patient? Please make sure that your advice is supported by the published evidence.
Discussion
In many ways, this is an ideal subject area for a discussion-based CET exercise. There is some refereed and well-accepted published evidence establishing a significant, though by no means absolute, link between nutrition and the progression of established age-related macular degeneration. The two studies, in particular, that were flagged up in this exercise and with which participants had to be familiar were the original AREDS and the more recent AREDS2 studies.
Those who submitted the outcomes of their discussions without mention of any research were felt by our CET panel not to have met the requirements of the task in hand. This point, it was felt, was worth underlining because the reason this area is ripe for interactive CET is also the same reason that it is important to be able to cite any published evidence. Nutrition is just one of many influences upon AMD.
Moreover, the very nature of AMD as a slow degenerative ageing process means that there are so many variables acting over such a long time upon the eye that high values of significance of association is unlikely. The subject area is, therefore, ripe for the injection of viewpoint and opinion. The same point, though with different emphasis, might apply to other topics such as the influence of blue light or the effect upon reading of colour filters.
While it is important for a professional to be able to offer their expert view in any area that is of relevance, and where a good understanding of this may be to the benefit of the patient, it is essential to be aware of any underlying supportive published evidence base. Indeed, now the GOC has introduced the Standards of Practice guidelines, there is no debate about this and this was therefore the stance taken with this exercise.
That said, most respondents did cite at least one reference source and the majority concurred in their overall view. Almost everybody agreed that the images (above) and description of the retinas of the case patient fell within the limits defined by AREDS as sufficiently established as to be influenced (potentially) by environmental variable change, such as dietary advice.
Many respondents, around half, picked up on the usefulness of using the Aston University flow chart of questions before deciding on the advice to be given. The vast majority of respondents then offered some variation upon the advice to increase the AREDS-cited nutrients within their diet, firstly through normal diet influence, and then with some form of supplementation.
The need for supplementation for many if not most was underlined in the majority of responses, reflecting awareness of the challenges in sufficiently changing AREDS nutrient input by dietary means alone. The vast majority of respondents were able to cite a suitable commercially available supplement product that matched the profile of supplement used in research.
One final point – a handful of respondents questioned the role of eye care practitioners in offering nutritional advice – ‘we are not dietitians’. This might be true, but neither are our patients simply eyeballs floating in space. Even if any final definitive advice was considered more appropriately delivered by another professional, advice on anything that might influence eye health surely is our preserve.
