Age-related Macular Degeneration and Alzheimer's Disease

The Age-related Macular Degeneration and Alzheimer’s Disease (AMDAD) Study is a pilot study to examine the relationship between age-related macular degeneration (AMD) and Alzheimer’s Disease (AD).  The purpose of this research pilot is to determine if patients with AD are more likely than other people to have the early stage of AMD.

Why is it so Important?

The question is of interest because the chemical composition of drusen in the retina (which signals the presence of macular degeneration) is similar to the composition of substances that are found in the plaque in the brains of people with Alzheimer’s Disease.  Thus, the causes of the two conditions may be similar.  Determining if patients with AD are more likely than other people to have the early stage of AMD would help researchers better understand both AD and AMD.

Study Design

The AMDAD study involves photographing the retinas of people with early stages of Alzheimer’s Disease to ascertain if these patients also have higher concentrations of drusen.  This is a cross-sectional study requiring only one session for ocular photography.  All patients with probable or possible Alzheimer’s Disease examined at the Penn Memory Disorders Clinic are asked to participate in the Study.  Approximately 100 patients will be included in the Study.  There are no eligibility criteria pertaining to age, gender, economic status, or race; however, the average age of patients seen at the clinic is in the mid-seventies.  Recruitment of patients is on-going and it is expected to be accomplished within 2 years from the initiation of the Study.  In this initial attempt to look for evidence of a relation between Alzheimer’s disease and early AMD, the prevalence of early AMD will be compared to the prevalence in the corresponding age groups in population based studies in the US, Australia and the Netherlands.

The study is funded by the Scheie Macula Research Fund and is a collaborative effort among CPOB, the Penn Low Vision Center and the Memory Disorders Clinic at Penn’s Alzheimer’s Disease Center. Click here for participating AMDAD study centers.

Description of the AMDAD Procedures

All eligible patients go to the Low Vision Center to have photographs taken of both their retinas, located at the back of the eye. Photographs are taken with a 60 degrees fundus camera.  To begin the process, the optometrist or ophthalmic technician at the Low Vision Center assesses the patient’s anterior segment for evidence of narrow angles.  If there is risk of angle-closure glaucoma, photographs will not be taken and the patient will be excluded from the study.  If there is no risk, dilating eye drops (1% tropicamide and 2.5% phenylephrine) are administered.  After approximately 20 to 30 minutes, the patient is seated at a fundus camera and is directed by the technician to position his/her chin on the chin rest.  A certified photographer takes two photographs of each eye (total of 4 flashes). Information is recorded on a Patient Visit Form [PDF, 73KB].

Films are logged and sent for processing and development to an outside imaging company.  Processed slides are labeled with ID number, name code, and date by the photographer.

The pictures are interpreted by professional photograph graders in the Scheie Image Reading Center, who record their findings on an Evaluation Form [PDF, 63KB]. A report of the findings [PDF, 12KB] on whether signs of AMD or other eye conditions were detected is provided to the patient, his/her caregiver, and, if requested, to the patient’s eye doctor or primary care physician.

CPOB’s Role in AMDAD

The CPOB serves as both the AMDAD Coordinating Center and Photograph Reading Center

Click on the links to learn more about the services of the Coordinating Center and the Scheie Image Reading Center.