Editor’s Note: Ford Vox is a physician specializing in rehabilitation medicine and a journalist. He is a medical analyst for NPR station WABE-FM 90.1 in Atlanta. He writes frequently for CNN Opinion. Follow him on Twitter @FordVox. The opinions expressed in this commentary are solely those of the author.

Story highlights

Widow says autopsy showed Robin Williams had Lewy body dementia

Ford Vox: Misdiagnosis of hard-to-spot disease understandable in a person known for manic performances

Vox: Lewy body dementia needs advocate for more research, like Michael J. Fox does for Parkinson's

CNN  — 

Robin Williams’ widow is speaking out about the disease process she blames for taking her husband’s life. She wants his millions of fans to know the legendary comedian and actor didn’t so much take his own life, as was widely reported in August 2014, but rather had it taken from him.

It wasn’t until his autopsy that she learned he was suffering from a relatively unknown brain disorder called Lewy body dementia. Susan Williams, who was in a years-long relationship with the comedian before marrying him in 2011, told ABC News this week about her husband’s rapid decline in the months before his death.

Doctors had diagnosed Robin Williams with Parkinson’s disease in November 2013 after he developed a classic resting tremor in his left hand. Americans know Parkinson’s well, both because of its prevalence – it affects about 1 million people in the United States – as well as for a particularly famous advocate with the condition, Michael J. Fox.

Unlike Fox, Williams reportedly wasn’t ready to share that diagnosis with the world before his death. But as his widow is now emphasizing, it wasn’t the right diagnosis.

Williams’ struggles with cocaine and alcohol in earlier years, and relapses with alcoholism in the 2000s were well-reported and discussed by Williams himself. His relapse into heavy alcohol use in his 50s in particular, which led to a couple of stints in rehab, could have hit his brain hard, but that’s not why he developed Lewy body dementia.

That even Williams was “misdiagnosed” reflects the severe diagnostic challenge the disease presents. In fact, misdiagnosis is more likely than correct diagnosis: Gold-standard brain autopsy results often uncover the characteristic signs of Lewy body dementia in people who doctors thought simply had Parkinson’s, or another more common dementia, Alzheimer’s.

HOLLYWOOD - NOVEMBER 09:  Susan Schneider and Robin Williams arrive at the premiere of Walt Disney Pictures' 'Old Dogs' at the El Capitan Theatre on November 9, 2009 in Hollywood, California.  (Photo by Jason Merritt/Getty Images)
Robin Williams' wife: 'Lewy body dementia killed Robin' (2015)
01:23 - Source: CNN

I can’t help but think about Williams’s frenetic performances and how he often appeared to be on the verge of a manic state, pushing his brilliant mind to the limits of human capacity. One wonders if a person who’s so known for standing out from the crowd, for being the one-in-a-million center of attention, suffers a bit when it comes to the objective clinical examination.

Any doctor who examined him as a patient also had to navigate a trove of associations of Robin Williams as a most unusual and memorable performer.

Was Williams’ neurologist less likely to suspect Lewy body dementia because some of the free associations and flights of fancy that might raise eyebrows in anyone else just don’t strike much of a chord when you’re looking at a cultural touchstone in front of you who’s known for nothing less?

In fairness, Alzheimer’s can sometimes be clinically indistinguishable from Lewy body dementia, especially when the disease is advanced. And Parkinson’s symptoms, like a resting tremor and stiffness, are also typical of Lewy body dementia. A common presenting symptom is an apparent new onset of Parkinson’s. Most researchers think Parkinson’s and Lewy body dementia are on a spectrum and that there are many key links underlying their manifestations.

As time goes on, most Parkinson’s patients will develop mild cognitive impairment such as occasional memory lapses, and some studies indicate that up to 80% will develop true dementia.

Though Lewy body dementia is the second-leading cause of dementia in Americans after Alzheimer’s disease, we don’t know a lot of basic facts about the illness.

Lewy bodies, named after German neurologist Friedrich Lewy, who reported discovering them under the microscope in 1923, are actually bundles of proteins called alpha-synuclein and are embedded inside brain cells

But we don’t even know if the so-called “bodies” themselves are causing brain dysfunction or represent the aftermath of the brain’s attempts to repair itself. To confuse the matter even further, some people have severe buildups of Lewy bodies at autopsy but had no symptoms of Lewy body dementia when they were alive.

Lewy body dementia has two particularly useful early symptoms. The presence of REM sleep behavior disorder, where sufferers actually act out their dreams and can injure themselves (and anybody around them) in the middle of the night, and the early onset of visuomotor impairments that result in incoordination and falls are important clues to the presence of Lewy body.

Susan Williams said her husband had started experiencing visuomotor problems, describing one accident to ABC when the performer, hovering over the sink with a bloody wound on his head, told her he’d “miscalculated” where the door was.

Lewy body dementia won’t be suspected unless there are deficits in cognitive functions severe enough to warrant a dementia diagnosis. That means a clinician will need to find significant problems in some combination with attention, decision-making, spatial reasoning and memory. Sometimes a short test given in the clinic is enough.

Other patients may require more involved testing performed by a neuropsychologist. Once a true dementia is detected, other features such as fluctuation in cognitive performance, visual hallucinations and parkinsonism must be identified.

Even if Williams’ doctors were doing everything right, studies show that the usual clinical criteria we rely on to tip us off will miss more than 60% of patients who actually have the disease.

And even if he had been correctly diagnosed, no treatments exist to tackle the underlying causes of the disease. There’s no way to stop or reverse it. Not yet. The best management involves keeping people in a familiar living environment with adequate supervision for their safety. Medications used to treat Lewy body dementia can manage the disease’s many varying symptoms, and they can rapidly fill a medicine cabinet.

Someone with the disease may need a Parkinson’s medication called Sinemet for the motor symptoms such as gait instability, tremors and rigidity. They may need an antidepressant, an anti-anxiety drug, and they may even need an antipsychotic medication to help tamp down hallucinations and unsafe behaviors. A strong, heavy sleep medication may be necessary if the person has REM sleep behavior disorder to keep them safely in bed during the night.

Williams’ autopsy report tells us he was taking an antidepressant that’s useful for sleep, called Remeron, as well as Sinemet for his parkinsonism and an antipsychotic to take on an as-needed basis.

What about Susan Williams’ contention that Lewy body dementia drove her husband to suicide? He did experience distressing hallucinations, she said, and such symptoms are presumably why doctors prescribed him the antipsychotic. Erosion of his decision-making capacity could have lowered his threshold to cope with such symptoms.

Lewy body dementia and depression are certainly linked as well. In the biological sense, depression, whether due to a degenerative illness or in an otherwise healthy person, is still a serious disease. In providing additional medical context to Williams’ suicide, we shouldn’t discount the suffering of everyone else trying to manage depression.

Lewy body dementia needs a champion, such as Michael J. Fox and his foundation who have been pushing hard to find a cure for Parkinson’s disease.

Victims of diseases such as Lewy body dementia and Alzheimer’s can’t advocate for themselves unless they’re somehow diagnosed early in the disease process. Most people who will go on to develop these diseases won’t have the capacity to represent them as a cause once they’re diagnosed.

Hopefully, Susan Williams’ new crusade, which began by dramatically pointing out how her husband died without the right diagnosis, will push forward a wider cause: generating the attention and money we need to identify better ways of diagnosing and treating this mysterious condition.

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