Joe Biden: A clinical diagnosis

Joe Biden’s symptoms are characteristic of a specific type of dementia, which would immediately be obvious for any expert who observes him briefly on television. This disease belongs to the group of vascular dementias, which make up about 20 percent of all dementia cases, including stroke patients in whom the blockage of a major brain artery has damaged cognitively relevant brain areas.

Another significant subtype of vascular dementias is Binswanger's disease, also known as subcortical arteriosclerotic encephalopathy (SAE), which is most likely the disease from which Biden is suffering–a slowly progressing atherosclerosis of smaller brain arteries which evolves over years, often facilitated by high blood pressure. Consequently, this leads to chronic blood flow disturbances in certain subcortical structures containing fibers and nerve tracts that connect various brain areas or extend towards the spinal cord. These damaged brain structures can be detected through MRI scans.

Since this kind of dementia affects different brain structures than Alzheimer's disease, the symptoms are also mostly different. While Alzheimer's disease develops exclusively cognitive symptoms and possible behavioral disorders, SAE also affects motor systems. This typically leads to the symptoms observed in Biden: slurred speech with a progressively quieter voice and a relatively mild and fluctuating Parkinsonian gait disorder. This results in a shuffling and constrained gait pattern, which Biden frequently tries to consciously hide in public with varying success, often appearing rather odd.

In Alzheimer's dementia, cognitive impairments primarily involve memory and learning abilities. Biden also shows weaknesses in this area, often directly or indirectly visible in numerous video sequences – for example, through the excessive use of teleprompters and briefings with very simple notes, which do not always suffice. However, the main and most characteristic cognitive impairment in Biden, typical for SAE, is an executive dysfunction.

This is a highly complex disorder involves so-called metacognitive processes, which flexibly coordinate multiple sub-processes to achieve a certain intention. This dysfunction in Biden can be observed in his recent CNN debate when he loses his train of thought and can't find it again, or similarly, when a line of thought fades away, or when, as recently at the G7 summit in Italy, he suddenly and seemingly inexplicably shifts his focus to something entirely irrelevant in that situation.

Similar to Alzheimer's disease, SAE typically progresses slowly and steadily. However, unlike Alzheimer's, SAE can also lead to sudden deteriorations due to an increased risk of (minor) brain infarctions caused by damaged blood vessels. To assess the progression of SAE in Biden, it's helpful to remember where he is cognitively coming from. He was once one of the most successful Democratic politicians, winning his Senate seat five times in a row and – hard to believe – was considered the best speaker among the Democrats for a time.

At the end of February this year, the White House physician Kevin O’Connor certified that the President was sufficiently fit for another term: “President Biden is a healthy, active, robust 81-year-old man who remains fit to successfully execute the duties of the Presidency.” O’Connor deemed the neuropsychological dementia assessment demanded by Republicans, such as the MoCA test, as unnecessary. Given Biden's obvious cognitive problems, this seems almost like medical malpractice.

This test, which Trump passed without issues, measures not only memory performance but also (among other things) the mentioned executive functions with two subtests: under time pressure, the patient must alternately connect letters and numbers, e.g., 1 - A - 2 - B - 3 - C, and then complete the seemingly simple clock test by drawing a clock with all 12 numbers in a given circle and setting the hands to 10 past 11. This simple task presents unsolvable problems for patients with executive dysfunctions. Given this context, it's hard to imagine Biden passing this test without errors.

A version of this article was first published on the German news blog “Die Achse des Guten” (www.achgut.com). German Version see here.

About the Author: Prof. Dr. med. Dipl.-Psych. Wolfgang Meins is a neuropsychologist, psychiatrist, neurologist, geriatrician, and adjunct professor of psychiatry. In recent years, he has primarily worked as a court expert in civil law. He is based in Hamburg, Germany.