Scattered throughout my childhood memories are many forms of Robin Williams; the mischievous genie in Aladdin, the loving father in Mrs. Doubtfire, the lost boy hidden within the serious man in Hook. His films served as a familiar blanket; one that I wrapped myself up in when I was sick and needed such warmth, curled up beside my father who shared my love for the soulful characters Robin Williams created. It wasn’t until I was older and beginning university that I came to appreciate his more serious acting repertoire. I watched Dead Poet’s Society because it is renowned for being sophisticated and intelligent – which suited the image I was trying to create of myself at the time. It moved me and my respect for the man only grew. The day after Robin Williams’ death was announced I watched Good Will Hunting for the first time and unashamedly cried my eyes out. A great actor, a man who spent his life making other people laugh, whose playful spark reminded me in many ways of my own dad, was gone. I never dreamed that only a year later, I would be one of many researchers working to understand a disease that changed his life: Dementia with Lewy Bodies (DLB).
What is Dementia with Lewy Bodies?
This is the question on many people’s’ lips since the revelation of Robin Williams’ diagnosis. DLB is a subtype of dementia, with approximately 15% of dementia patients’ symptoms falling under this characterization. This makes it the second most common dementia subtype, ranking just after Alzheimer’s Disease (AD) and above vascular dementia (VaD). Age of onset can be as early as 50 and rate of decline is approximately 10% per year. DLB gets its namesake from the presence of abnormal aggregates of protein called Lewy bodies in the cerebral cortex, brainstem and parts of the basal forebrain cholinergic system. These are thought to disturb neural processing and cause brain cells to die. Additionally, patients often present with AD pathology – such as amyloid plaques, which appear with similar density and distribution to that seen in AD. This affects symptomatology and contributes to the high rate of misdiagnosis in DLB.
What does Dementia with Lewy Bodies look like?
There is no easy answer to this question. DLB is notably heterogeneous and clinical profiling indicates it bears many similarities with both AD and Parkinson’s Disease (PD). Some core features have been identified however, including cognitive impairment in more than one domain, cognitive fluctuations, mild or spontaneous Parkinsonism and visual hallucinations. Unlike AD, memory impairment in DLB is not usually prominent early in the disease, with executive dysfunction and visuospatial difficulties more frequently reported at diagnosis. Patients’ fluctuations in cognition, mostly attentional, can occur on a day-to-day, hour-to-hour or minute-to-minute basis. Approximately 70% of patients experience parkinsonism symptoms such as bradykinesia, gait disturbances and limb rigidity. Visual hallucinations, while a hallmark of DLB, are only seen in two-thirds of patients, lending to the frequent misdiagnosis of AD. These hallucinations are described as colourful, vivid and three-dimensional mute animations. Depression is also common, with 40% of patients experiencing a major depressive episode. REM Sleep Behaviour Disorder predicts disease onset in a number of patients (as described in my previous blog) and may reflect underlying pathology as it rarely occurs with amyloidpathy or taupathy, marked features of AD.
Why is more research into Dementia with Lewy Bodies essential?
A focal issue with dementia is accurate clinical diagnosis; the dementia subtypes often appear similar in presentation which causes uncertainty for clinicians. DLB has a high rate of misdiagnosis, ranging from 34-65% of patients after post-mortem examination. Definitive conclusions cannot be drawn until autopsy, from which underlying pathological features can be discerned. Neuroimaging methods may assist diagnosis with studies indicating preservation of the hippocampal and medial temporal lobe regions distinguish DLB from AD. There are still gaping holes in the knowledge accumulated around this disorder and more research needs to be conducted in order to fill them, allowing better understanding of causes, pathophysiology, treatments and management of DLB. Of key importance here is establishing more stringent and robust methods of diagnosis as misdiagnosis can lead to sub-optimal or dangerous treatments. Central to this worry is incorrect pharmacological treatment; while patients generally have more positive responses to cholinesterase inhibitors than AD patients, neuroleptic drugs provided to ease psychiatric symptoms can cause extremely sensitive responses in 50-60% of DLB patients. Sudden onset or worsening of parkinsonism and impaired consciousness is reportedly due to this sensitivity and increases the risk of mortality 2-3 fold. In order to combat these issues, a focus on more extensive DLB research is needed.
While the news of Robin Williams’ death saddened me, the uncovering of his struggle with DLB struck another chord of sorrow. I empathized for him and his family’s experience of the progressive decline of his mind and body. But I recognised the solitary positive of this event; this hugely famous well-publicized figure that held a fond place in many people’s hearts had drawn attention to a relatively unknown disease. This brings with it the potential for increased public awareness and advocacy, improved services for carers and patients alike and promotion and encouragement for research into the dementia. Every cloud has a silver lining, even when it is the passing of a personal childhood hero.
McKEITH, I. G. (2002). Dementia with Lewy bodies. The British Journal of Psychiatry, 180(2), 144-147.
McKeith, I. G., Burn, D. J., Ballard, C. G., Collerton, D., Jaros, E., Morris, C. M., … & O’Brien, J. T. (2003, January). Dementia with Lewy bodies. InSeminars in clinical neuropsychiatry (Vol. 8, No. 1, pp. 46-57).
McKeith, I., Mintzer, J., Aarsland, D., Burn, D., Chiu, H., Cohen-Mansfield, J., … & Playfer, J. (2004). Dementia with Lewy bodies. The Lancet Neurology,3(1), 19-28.
Metzler-Baddeley, C. (2007). A review of cognitive impairments in dementia with Lewy bodies relative to Alzheimer’s disease and Parkinson’s disease with dementia. Cortex, 43(5), 583-600.