Dementia: Getting a Diagnosis

The diagnosis of dementia is based on a combination of data, including changes in cognition (thinking), mood, behavior and adaptive functioning while ruling out known conditions that might mimic dementia but are not related to dementia (such as sensory loss, delirium, depression, or environmental stressors). This means the eventual diagnosis of dementia is one of exclusion, commonly referred to as the Differential Diagnosis. The caregiver’s knowledge of the individual’s day to day communication and functioning is essential. For individuals with Intellectual/Developmental Disabilities finding a baseline is the first step in the diagnosis. This can also be one of the more difficult parts in the process due to a variety of factors, including: poor-record keeping from childhood, lack of ongoing involvement from family, involvement of multiple staff members (due to high rates of turnover) and inconsistencies in the doctor-patient relationship over the individual’s lifespan.

Step 1: Obtaining a Baseline 

For individuals with I/DD, finding a baseline is one of the most important parts of a possible dementia diagnosis. Currently the most recent and thorough screening instrument is the NTG-EDSD or the National Task Group – Early Detection Screen for Dementia. It was specifically made to create a baseline of thought function in individuals with I/DD but is not a diagnostic instrument or in other words, it’s results alone cannot confirm Alzheimer’s or other related dementia. It is recommended that this instrument be used yearly, beginning at age 40 for individuals with Down syndrome and at the time of suspected thought function change for other individuals with I/DD. 

Step 2: Finding a Memory Clinic

If you have concerns about memory loss, thinking skills or behavior changes in yourself or a loved one, contacting a nearby clinic or your primary care physician is an important step toward diagnosis and treatment. The Wisconsin Alzheimer’s Institute has developed 44 Memory Clinics in Wisconsin and Upper Michigan to provide education, mentorship and support to over 200 physicians, physicians assistants, nurse practitioners, psychologists, social workers, nurses and more. If you are currently looking for a memory clinic near you please click on the picture below to bring up a list of available clinics near you. Make sure to have a detailed medical history and any/all early detection screens (NTG-EDSD) you have filled out as this will make the most out of your visit. 


Step 3: The Differential Diagnosis

As previously stated the final diagnosis for Alzheimer’s is one of exclusion, meaning that all other possible causes for dementia symptoms must be ruled out. Below is a flow chart describing the process of obtaining an Alzheimer’s/dementia diagnosis. Once your health care team has identified Alzheimer’s/dementia it doesn’t mean the differential diagnosis stops because there is no way to have a one hundred percent positive Alzheimer’s diagnosis at this point in time. It is always a good idea to keep looking for other things that could mimic dementia symptoms.