Neurology – Helen Jaques

Heavy alcohol consumption can lead to essential tremor

April 27, 2009 26 Comments

tremor Drinking three or four alcoholic drinks a day can double the risk of developing essential tremor – or ‘the shakes’ – in old age, suggest new findings from a Spanish research group. In a report published earlier this year, the same researchers found that individuals with essential tremor were four times more likely to develop Parkinson’s disease than people without the shakes.

Essential tremor is a progressive neurological disorder characterised by uncontrollable shaking of the hands or, in some cases, the head, jaw, face, feet or tongue. An estimated 650,000 people in the UK and five million in the US over the age of 60 are affected by this disorder.

Scientists don’t really know what causes essential tremor. They do know, however, that people with this disorder have damage in the cerebellum part of their brain, including loss of neurons called Purkinje cells. Given that alcohol is known to be toxic to the cerebellum, Louis and colleagues investigated whether alcohol consumption had an effect on the development of essential tremor.

This study assessed lifetime alcohol consumption and neurological symptoms in more than 3,000 people aged 65 years or older. At initial assessment, more than half (1,838 people; 56%) of the participants were found to have had at least one alcoholic drink per day over their lifetime. During the subsequent 3 years, 76 people developed essential tremor.

Individuals who drank 3-4 alcoholic drinks each day were twice as likely to develop essential tremor than those who drank less. In fact, just one or two drinks a day increased the risk by 30%.

The authors suggest that ethanol, a known cerebellar toxin, lowers the threshold for developing ET – a disorder involving the cerebellum. It is also possible that individuals who develop essential tremor use alcohol to self medicate, thus making their shaking worse.

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Louis E et al. (2009) Population-based study of baseline ethanol consumption and risk of incident essential tremor. Journal of Neurology, Neurosurgery & Psychiatry 80 (5): 494-497 DOI: 10.1136/jnnp.2008.162701

Neurology

Jeremy Paxman and Jane Asher to donate brains for research

April 20, 2009 No Comments

Brainiacs Jeremy Paxman and Jane Asher have both pledged to donate their brains for research into Parkinson’s disease – after they’re dead of course.

The Parkinson’s Disease Society has launched a campaign to increase awareness about brain donation as part of national Parkinson’s Awareness Week.

According to research commissioned by the Parkinson’s Disease Society, only 27% of people have considered donating their brain. Conversely, 29% of people know someone affected by Parkinson’s disease.

The Society is hoping to double the number of people on the Parkinson’s Brain Donor Register by the end of 2009. Over 1,000 people have already signed up.

Parkinson’s is an incurable neurodenerative disease that is caused by loss of dopamine-producing nerve cells in the brain. Dopamine is responsible for co-ordinating movement, so sufferers of Parkinson’s disease have trouble with movements such as walking and talking. Parkinson’s disease is characterised in particular by hand tremor, which is the first symptom for 70% of affected individuals.

Only humans get Parkinson’s disease, so it is crucial that scientists have access to human brain tissue in order to develop new treatments. Researchers hope to understand the causes and pathology of the disease by comparing brains from Parkinson’s patients with brains from healthy individuals – that’s where the Brain Bank donors come in.

The Parkinson’s Brain Bank is the UK’s largest human brain bank dedicated to Parkinson’s disease and is based at Imperial College London.

After the death of a donor, the team on call at the Brain Bank dashes to collect the brain, spinal cord and a sample of cerebrospinal fluid within 24 hours. The brain is then weighed, measured and examined, and subsequently brain is divided into two halves, which are preserved differently. The right half of the brain is preserved by quickly freezing it, while the left half is placed in a fixative for about four weeks. Before freezing, tissue samples are taken from 21 different points and the nerve cells are carefully studied under a microscope.

The brain tissue is then provided to researchers around the world who are working towards a cure for Parkinson’s. Since 2002, the Parkinson’s Brain Bank has supplied tissue to more than 80 research projects around the world – including projects in the UK, Europe, USA and Canada.

Neurology

A stressful job doubles the likelihood of stroke – but only for men

January 13, 2009 No Comments

job-stress A study published in Annals of Internal Medicine has found that men with a stressful job are twice as likely to have a stroke than are men with less demanding jobs. Interestingly, there was no correlation between job stress and incidence of stroke among women.

A stroke occurs when the blood supply to the brain is cut off, for example when a clot blocks one of the blood vessels supplying the brain. Stroke can cause permanent neurological damage and even death, and has been linked to stress for quite some time.

Tsutsumi et al. interviewed 3,190 Japanese men and 3,363 Japanese women from a variety of job backgrounds, including managers, professionals, technicians, clerks, salespeople, farmers, craftsmen and labourers. The level of occupational stress experienced by these workers was evaluated and participants were placed into four stress categories: high strain (high job demand + low job control); active job (high job demand + high job control); low strain (low job demand + high job control); and passive job (low job demand + low job control).

Over the next 11 years, 91 men and 56 women experienced a stroke. Men under high job strain – i.e. those with lots of demands on their shoulders and with little control of their workload – were twice as likely to experience a stroke than were men under low strain. In women, however, the incidence of stroke was the similar among those with a stressful job and those under less strain.

Among men, the association between job stress and stroke lessened somewhat when other risk factors for stroke, such as obesity and high blood pressure, were taken into account, suggesting that pre-existing chronic diseases and an unhealthy lifestyle up the chance of stroke in stressed out employees.

The authors of the study suggest that that the difference between the sexes could be because women approach stressful jobs differently to men or because more women than men work part-time.
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Akizumi Tsutsumi, Kazunori Kayaba, Kazuomi Kario, and Shizukiyo Ishikawa (2009) Prospective Study on Occupational Stress and Risk of Stroke Arch Intern Med 169 (1): 56-61

Neurology

Skin test to detect Parkinson’s disease

October 10, 2008 No Comments

A recent study published in the Journal of Neuropathology & Experimental Neurology has shown that neural signs of Parkinson’s disease can be identified by taking a simple skin sample.

Parkinson’s disease is a progressive neurodegenerative disease that affects about 1 in every 500 people in the UK. There is no biochemical test to definitively diagnose Parkinson’s disease; diagnoses are instead made on the basis of various clinical assessments. Parkinson’s disease is, however, characterized by the presence of Lewy bodies (LBs) – tiny protein deposits in nervous tissue.

LBs can only be identified from a tissue sample, which is then stained and examined under a microscope (see right). These proteins tend to accumulate in the central nervous system and in the sympathetic ganglia, nervous tissue that runs like train tracks down either side of the spine – places that are nearly impossible to get biopsy samples.

In this study, the authors looked for LBs in various tissues in 279 patients undergoing autopsy. A total of 85 patients had evidence of LBs in their central nervous system, so were diagnosed as having had a LB disease (LBD) – Parkinson’s with or without dementia, dementia with LBs or LB-related progressive autonomic failure.

The authors then examined skin biopsy samples taken the patients with proven LBD and found that 20 (23.5%) patients showed LB pathology in the cutaneous nerves of skin samples. None of the 194 individuals who did not have LBD showed evidence of LBs in skin samples; therefore, the skin test didn’t mistakenly identify any patients as having LBD.

More specifically, LBs were found in the skin of 70% of patients who had Parkinson’s disease with dementia and in 40.4% of those who had dementia with LBs. On the other hand, LB pathology was found in the skin of only 20% of patients who had subclinical LBD, i.e. patients who would have had few symptoms of LBD but not enough signs to meet all the criteria for a diagnosis. This skin biopsy test might not, therefore, be a useful test for early diagnosis in individuals suspected of having LBD.

When the authors looked at the clinical records of the patients that they had autopsied, they found that LBD patients who had evidence of LB pathology in their skin were more likely to have been bedridden and unable to walk independently before they died than were those patients with LBD who did not have cutaneous LB pathology (P<0.001 style="font-style: italic;">P=0.065, respectively). This finding suggests that skin biopsy testing could be used to predict which patients’ physical functioning might be affected most seriously by their disease, and physiotherapy could be prescribed accordingly.

Ikemura et al.’s study is the first to find evidence of LB pathology in the skin of patients with LBD; however, their results do not support the use of skin biopsy as an early diagnostic test. Testing for LBs in the skin could be used to confirm the diagnosis in a patient with clinical Parkinson’s disease or dementia with LBs and to predict the effect the disease might have on their physical functioning, both of which could help clinicians tailor treatment.

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Ikemura M, Saito Y, Sengoku R, Sakiyama Y, Hatsuta H, Kanemaru K, Sawabe M, Arai T, Ito G, Iwatsubo T, Fukayama M, Murayama S (2008). Lewy Body Pathology Involves Cutaneous Nerves. J Neuropathol Exp Neurol, 67 (10), 945-953 PMID: 18800013

Arts, Events, Neurology

Music, memories and the mind

September 15, 2008 No Comments

Yesterday I went down (no, make that up – up a very steep hill, on my bike) to Jackson’s Lane in Highgate for some neurology theatre – not of the surgical kind but a performance of the play Reminiscence.

Inspired by a case study published by the neurologist Oliver Sacks, the play tells the story of elderly Mrs O’Connor, who, following a stroke, experiences temporal lobe seizures accompanied vivid auditory hallucinations. Although she recognises the songs she hears, Mrs O’Connor can’t put her finger on where she knows the melodies from. Through these seemingly familiar “experiential hallucinations”, she re-lives events that she believes are buried memories from her distant past.

As far as I was concerned, a key aspect of the play was how Theatre DaCapo approached a dry medical case study and transformed it into an engaging piece of theatre. Instead of depicting the story of Mrs O’Connor through the objective view of the neurologist, the whole case study is portrayed from the perspective of the patient, bringing an altogether more human angle to the case study.

Thus, the onus was on the theatre group to represent effectively the subjective, difficult-to-quantify experiences of a neurology patient. In order to do this, the five-man group of actors used clever staging and a myriad of props and visuals.

In scenes such as the one shown here, actors popped out from between the folds of a giant white backdrop, portraying in this instance the characters Mrs O’Connor begins to see as her hallucinations gather more sensory components. In another scene, the actors, posing as doctors, appeared in the windows within the backdrop and bounced neurological terms off each other, depicting Mrs O’Connor’s disorientation at the mass of medical information she was being bombarded with.

Folk songs – reworked in a classical style and performed by the actors – and the pitching and swaying of the scenery indicated when Mrs O’Connor was experiencing a seizure.

I was also interested in how the play was going to depict the neurology that underlines the case study. In the scene shown here, a dish of jelly was used to represent the brain and the affected region scooped out with gusto to demonstrate how the seizures and hallucinations could be cured by surgical removal of the damaged part of the brain.

One of the issues raised by the play is whether the hallucinations Mrs O’Connor experiences actually reflect real memories, or are false and are in fact the result of Mrs O’Connor’s psychological motivation to come to terms with her past. This issue was one of many debated in a a panel discussion after the play in which the audience quizzed the director Michael Callahan, clinical psychologist and Mind Hacks blogger Dr Vaughan Bell, and actors Ian Harris and Katie Pattison. During the discussion, we touched on whether the verity or not of our memories is important – although they may be revised through telling at different points in our life, they still represent an important part of our identity.

It was a refreshing change to learn about a clinical case study through such an imaginative and well-realised play rather than from a journal paper.

Reminiscence will be performed at 8pm at Jackson’s Lane theatre until Saturday 20th September (matinee 2pm Wednesday 17th September). For tickets, contact the box office on 0208 341 4421 or buy online at jacksonslane.org.uk

(Thanks to Theatre-DaCapo.co.uk for the photos)