Increased risk of Parkinson’s disease in methamphetamine users, CAMH study finds

For Immediate Release - July 26, 2011- (Toronto) - People who abused methamphetamine or other amphetamine-like stimulants were more likely to develop Parkinson’s disease than those who did not, in a new study from the Centre for Addiction and Mental Health (CAMH).

The researchers examined almost 300,000 hospital records from California covering 16 years. Patients admitted to hospital for methamphetamine or amphetamine-use disorders had a 76 per cent higher risk of developing Parkinson’s disease compared to those with no diagnosis.

Globally, methamphetamine and similar stimulants are the second most commonly used class of illicit drugs.

“This study provides evidence of this association for the first time, even though it has been suspected for 30 years,” said lead researcher Dr. Russell Callaghan, a scientist with CAMH. Parkinson’s disease is caused by a deficiency in the brain’s ability to produce a chemical called dopamine. Because animal studies have shown that methamphetamine damages dopamine-producing areas in the brain, scientists have worried that the same might happen in humans.

It has been a challenge to establish this link, because Parkinson’s disease develops in middle and old age, and it is necessary to track a large number of people with methamphetamine addiction over a long time span.

The CAMH team took an innovative approach by examining hospital records from California – a state in which methamphetamine use is prevalent – from 1990 up to 2005. In total, 40,472 people, at least 30 years of age, had been hospitalized due to a methamphetamine- or amphetamine-use disorder during this period.

These patients were compared to two groups: 207,831 people admitted for appendicitis with no diagnosis of any type of addiction, and 35,335 diagnosed with cocaine use disorders. A diagnosis of Parkinson’s disease was identified from hospital records or death certificates. Only the methamphetamine group had an increased risk of developing Parkinson’s disease.

While the appendicitis group served as a comparison to the general population, the cocaine group was selected for two reasons. Because cocaine is another type of stimulant that affects dopamine, this group could be used to determine whether the risk was specific to methamphetamine stimulants. Cocaine users also served as a control group to account for the health effects or lifestyle factors associated with dependence on an illicit drug.

“It is important for the public to know that our findings do not apply to patients who take amphetamines for medical purposes, such as attention deficit hyperactivity disorder (ADHD), since these patients use much lower doses of amphetamines than those taken by patients in our study,” said Dr. Stephen Kish, a CAMH scientist and co-author.

To put the study findings into numbers, if 10,000 people with methamphetamine dependence were followed over 10 years, 21 would develop Parkinson’s, compared with 12 people out of 10,000 from the general population. “It is also possible that our findings may underestimate the risk because in California, methamphetamine users may have had less access to health-care insurance and consequently to medical care,” said Dr. Callaghan.

The current project is significant because it is one of the few studies examining the long-term association between methamphetamine use and the development of a major brain disorder. “Given that methamphetamine and other amphetamine stimulants are the second most widely used illicit drugs in the world, the current study will help us anticipate the full long-term medical consequences of such problematic drug use,” said Dr. Callaghan.

Media Contact: Michael Torres, Media Relations, CAMH; 416-595-6015

The Centre for Addiction and Mental Health (CAMH) is Canada's largest mental health and addiction teaching hospital, as well as one of the world's leading research centres in the area of addiction and mental health. CAMH combines clinical care, research, education, policy development and health promotion to help transform the lives of people affected by mental health and addiction issues. CAMH is fully affiliated with the University of Toronto, and is a Pan American Health Organization/World Health Organization Collaborating Centre.

RHINORRHEA IN PARKINSON'S DISEASE

26th July 2011 - New research

Movement Disorders [2011] 26 (2) : 320-323 (Chou KL, Koeppe RA, Bohnen NI.)

Rhinorrhea is nasal discharge, commonly referred to as a runny nose. For more information go to Rhinorrhea. Although, nasal discharge is usually assumed to occur for a variety of reasons such as colds, flu or allergies, it is a common symptom in Parkinson's Disease. Researchers have found that people with Parkinson's Disease multiplied the likelihood of nasal discharge 5 times the average. This is after other possible causes had been accounted for.
Over two thirds (68%) of people who had Parkinson's Disease reported nasal discharge. There was no relationship with age or severity of symptoms. The nasal discharge of over half (52%) of people with Parkinson's Disease was accompanied with light headedness. The symptom of lightheadedness is uncommon in people who do not have Parkinson's Disease, occurring in less than 1 in 10. Another recent study found similar results.  The frequency of nasal discharge can lead to a reduction in the sense of smell, which is common in Parkinson's Disease.

It is not clearly known what causes this relationship. Nasal discharge occurring so frequently in Parkinson's Disease is not directly due to low dopamine, and a previous study found no relationship between rhinorrhea and dopamine agonists.

Single and dual task gait training in people with Parkinson's Disease: A protocol for a randomised controlled trial

From Northwest  Parkinsons Foundation:      

 

Difficulty performing more than one task at a time (dual tasking) is a common and disabling problem experienced by people with Parkinson disease (PD). If asked to perform another task when walking, people with PD often take shorter steps or walk more slowly.

Currently there is uncertainty about whether clinicians should teach people with PD to avoid dual tasking or whether they should encourage them to practice dual tasking with the hope that practice will lead to enhanced performance. This study will address this issue by comparing single to dual task gait training.Methods and design: A prospective randomised clinical trial is being conducted.

Sixty participants with idiopathic PD will be recruited, provided they score I-IV on the modified Hoehn and Yahr (1967) scale, and fulfil other inclusion criteria. Participants will be randomly allocated to either a single or dual task gait training group.Both groups will receive 12 hours of walking training over 4 weeks. The single task group will undertake gait training with cueing strategies to increase step length.The dual task group will train to improve step length when walking and performing a variety of added tasks.

Both groups will receive a tailored home program for 6 months.Blinded assessors will conduct four assessments: two baseline assessments, one post intervention and one at 6 months follow-up.

The primary outcome measure will be step length when dual tasking over 8m.Secondary outcome measures include: spatiotemporal gait parameters when walking under single and dual task conditions, measures of executive function, the timed up and go test, measures of community mobility, and quality of life.

All analyses will be based on intention to treat principle. Discussion. This trial will examine the immediate and longer term effect of dual task walking training as compared to single task training in people with idiopathic PD, at the impairment, activity, and participation levels.

It has the potential to identify a new intervention that may improve and maintain walking beyond the laboratory. The results of this trial will provide guidance forclinicians in the development of walking training programs for people with PD.Trial Registration: ACTRN12609000791235