ODs Play Key Role in Dementia Diagnosis/Care

Optometrists are increasingly on the front lines of diagnosis and management of individuals with neurodegenerative disorders.

Individuals with Alzheimer’s and other forms of dementia have a higher risk of coexisting diseases, such as macular degeneration, glaucoma and diabetes, says Cheryl Letheren, OD, of London, Ontario. They also demonstrate characteristic retinal findings. “We already know other neurodegenerative conditions are in the eye, so it’s the next step to understand that patients are statistically likely to have Alzheimer’s if they have these other diseases and vice-versa,” Dr. Letheren says.

Even patients with mild cognitive impairment can have problems with fixation andanti-saccade, which can be pinpointed with eye tracking during the exam, Dr. Letheren suggests. Additionally, high-tech tools such as OCT-A can detect changes in vascularity, which could indicate neurodegenerative disease. “We now know retinal thickness may not be as accurate as we once thought, but there are several studies looking at OCT and OCT-A technology in regard to neurodegenerative diseases, and especially in Alzheimer’s and Parkinson’s.”

Beyond testing, optometrists should be aware of other possible telltale neurodegenerative signs, including vague answers from older patients about their medical history, if they express problems adjusting from light to dark rooms or if peripheral vision issues are apparent outside of typical visual fields. In the latter, one example would be if an older patient has difficulty looking at the doctor and also noticing an object in their periphery, Dr. Letheren explains. Other cues would be if a patient suddenly exhibits problems with color perception, such as showing up to the exam wearing mismatched colored clothing when they had always been impeccably dressed, she suggests.

“These are functional cues that aren’t necessarily ones that we measure during an exam, but they can certainly pop up when we are talking to the patient and their family,” Dr. Letheren adds.

Management Consideration

If the patient is known to have a cognitive impairment, Dr. Letheren suggests the individual bring a family member to the exam, along with their hearing aid, glasses and information about their history in a binder if they aren’t tech savvy and already have it on their phone. She will also give the patients instructions printed in large letters so it’s easier for them to see.

For those patients starting to lose their ability to read letters, Dr. Letheren recommends using a number chart or a non-verbal one like a tumbling E.

She also suggests keeping the questions simple. “What we’re looking for is functional vision. We want to make sure they are safe at home or the nursing home, so that doesn’t necessarily mean they need to have 20/20 vision,” Dr. Letheren says.

In patients with 20/40 acuity who can still see faces and their vision is still clear enough to walk without difficulty—but they continuously lose their glasses or have their spectacle lenses inadvertently taken by another resident at the nursing home—Dr. Letheren suggests that replacing their glasses on a regular basis might not be the best option.

Red Flag Falling Risks

Falls are a significant factor with these patients because they are generally losing their depth perception and may also have vision distortion due to glaucoma or other eye diseases, so clinicians should help make sure their homes are safe, Dr. Letheren suggests. This could include suggesting markings on the floor near steps, lit hallways, clutter-free floors, and if the patient is in a new environment, they have time to “walk the wall,” she says.


When treating older populations, in general, a good rule of thumb is to be a bit more patient and to also give these individuals more time to navigate in and out of the exam room, she says.

Hearing, vision and cognitive impairment commonly co-occur in older people, yet the rate of recognition and appropriate management of these patients is low. Delving into this issue, a new study offers clinicians practice recommendations to manage these patients with concurrent conditions.

Published in the June issue of Gerontology, the recommendations were created by an international interdisciplinary team of clinicians and academics representing specialists in hearing, vision and cognitive impairment in older people.

The publication represents a rapidly growing interest in the new health sciences field of sensory-cognitive health in aging, says researcher and professor Iracema Leroi, MD, FRCPC, MRCPsych, of the Global Brain Health Institute, Trinity College Dublin.

For optometrists, Dr. Leroi offers the following advice: “Please consider cognitive impairment in all older patients with vision impairment. This will be important for their uptake and renewal of prescriptions and may also impact their ability to self-report visual difficulties.”

Sensory function is critical in aging-related cognitive impairment, as demonstrated by a high prevalence of hearing and vision issues in people with dementia, which may exceed 85%, she adds. “The impact on dual sensory impairment on cognitive-functional ability, behavioral disturbance and progression of dementia is even greater than single sensory impairment. Moreover, single or dual sensory impairment increases the risk of developing dementia and represents potential modifiable risk factor for dementia,” she explains.


As part of the recommendations, the study suggests professionals assessing vision should consider the impact of hearing and cognitive impairments on evaluations of vision.

Recommendations in this area include:

  • Appointment letters should remind patients to bring their optimal hearing aids to the exam and provide information ahead of time about what to expect regarding visual assessment.

  • Increase awareness of environmental issues, such as conducting testing in a quiet environment, one-on-one, and ensure the individual can see the test administrator’s face and gestures.

  • Allow adequate time for appointments with opportunities for breaks.

  • Consider home evaluation visits if appropriate.

  • Include caregiver/family members to help recall history on hearing problems and allow them to accompany the patient during the entire appointment.

  • Consider alternative approaches to assess visual acuity such as Teller Acuity Cards and ETDRS letter charts that may work across a spectrum of cognitive impairment.

  • Refer to existing guidance from organizations such as the Royal College of Ophthalmologists and the College of Optometrists that have published recommendations on working with patients with visual loss and acquired cognitive impairment or dementia.

  • Routine provision of low-cost amplification devices during testing may help obtain accurate assessments, at minimum, when providing instructions.

  • Be flexible during the eye exam, since it may be difficult for patients to follow instructions. Consider simple, shorter, objective tests rather than subjective measures.

  • If cognitive status is unknown, and the clinician has sufficient training, consider asking relevant questions to probe cognitive status or performing adapted or sensory-appropriate versions of cognitive screens before the vision exam to determine the patient’s cognitive status to properly perform the evaluation.

The 15 recommendations from the study were classified into six domains: (1) awareness and knowledge, (2) recognition and detection, (3) evaluation, (4)  management, (5) support and (6) service and policy.

Since the field of sensory-cognitive health is still developing, many gaps in the evidence still exist, so the recommendations will need to be updated in the near future, Dr. Leroi says. 

The study is part of the SENSE-Cog research program (www.sense-cog.eu), funded by the EU for five years and led by Dr. Leroi. SENSE-Cog has been exploring the interlinks among age-related hearing and vision impairment in dementia by examining large-scale epidemiological datasets, adapting and validating cognitive assessments for hearing and vision impairment, developing screening tools for combined pathology and evaluating the impact of hearing and vision rehabilitation in people with dementia in a Europe-wide randomized controlled trial. The trial is scheduled to conclude in early 2022.

Littlejohn J, Bowen M, Constantinidou F, et al. International practice recommendations for the recognition and management of hearing and vision impairment in people with dementia. Gerontology. June 4, 2021. [Epub ahead of print].