Is there a link between Alzheimer's and AMD?

There may be an association between Alzheimer's disease and the onset of age-related macular degeneration (AMD), according to a report presented at the Association for Research in Vision and Ophthalmology (ARVO) meeting held in Fort Lauderdale, USA during May of this year.

Agnieshka Baumritter and colleagues from the Center for Preventive Ophthalmology and Biostatistics at the University of Pennsylvania, USA conducted a cross-sectional pilot study which analysed current population data to determine the expected rates of AMD and Alzheimer's and then compared this to the actual rates seen in one nursing home.

Fifty-nine patients with probable Alzheimer's consented (or their care providers consented) to be tested for AMD. Of these, 51 had a minimum of two gradable fundus photos taken. The mean age of subjects was 75 years. Late AMD was defined as the presence of choroidal neovascularization in one or both eyes, or the presence of geographic atrophy. Early stage AMD was defined as the presence of at least one large (>125 microns) drusen in one or both eyes.

The researchers observed late AMD in 5 (10%) of the 51 subjects, which was almost twice what would be expected in the general population. Early stage AMD was seen in 14 patients (30%), while in the general population this would probably only be seen in 6.5 people.

The authors conceded that the patient participation rate was low, however, they felt the study does indicate an association between the two conditions which requires further investigation.