Download 18 November 2015 Leanne Linard MP Chair Health and

18 November 2015
Leanne Linard MP
Chair
Health and Ambulance Services Committee
Parliament House
George St.
Brisbane QLD 4000
By email to: [email protected]
Dear Ms Linard
Re: Deep brain stimulation for paediatric mental health patients in Queensland
The Royal Australian and New Zealand College of Psychiatrists (RANZCP) welcomes the
opportunity to provide the Health and Ambulance Services Committee their views on deep
brain stimulation (DBS) treatment for paediatric mental health patients in Queensland.
In Australia DBS is a well-established procedure for the treatment of advanced movement
disorders, particularly Parkinson’s disease. It has also been used to a much lesser extent to
treat severe and medically intractable Tourette’s syndrome (TS) and obsessive compulsive
disorder (OCD), yet it is not an established procedure to treat these disorders.
Current research and clinical trials into the use of DBS to treat other psychiatric disorders
such as depression, addiction, and anorexia are emerging worldwide.
In Queensland, the Movement Disorders Clinic at St. Andrew’s War Memorial Hospital in
Brisbane provides DBS for patients with TS and OCD, however the majority of patients at the
hospital receive the treatment for Parkinson’s disease and other movement disorders. The
hospital has considerable experience administering the procedure by international standards
with approximately 800 DBS procedures carried out to date. A small number of DBS
procedures to treat Parkinson’s disease are conducted each year at the Princess Alexandra
Hospital in Brisbane. They are the only hospitals or clinics that conduct the DBS procedure in
Queensland.
There is little clinical evidence worldwide of the use of DBS to treat children or adolescents
for movement disorders or psychiatric disorders. It is rare for the DBS procedure to be used
to treat children or adolescents with psychiatric disorders, and in Australia it is not currently
used to treat children or adolescents with psychiatric disorders.
The RANZCP has prepared an information sheet overleaf on DBS. It provides information on
the procedure, clinical indications, side effects, patient selection and consent, and the use of
DBS in Australia.
PO Box 261, RBH Post Office QLD 4029 Australia
T +61 7 3852 2977 F +61 7 3852 2199
[email protected] www.ranzcp.org
ABN 68 000 439 047
The RANZCP are committed to helping the Queensland Government develop an effective
and robust Mental Health Act. If the Committee require further information with regards to
this submission they are welcome to contact the RANZCP policy officer, Judith Johnston on
(07) 3852 2977 or by [email protected].
Yours sincerely
Associate Professor Mohan Gilhotra
MBBS, MM, FRACMA, FRANZCP, FRCPsych
Chair, RANZCP Queensland Branch
Deep Brain Stimulation
Information Sheet
November 2015
working
with the
community
PO Box 261, RBH Post Office QLD 4029 Australia
T +61 7 3852 2977 F +61 7 3852 2199
[email protected] www.ranzcp.org
ABN 68 000 439 047
Deep Brain Stimulation
Introduction
Deep Brian Stimulation (DBS) is a typically reversible therapeutic medical procedure that has been used
to successfully treat patients suffering from movement disorders such as Parkinson’s disease, dystonia,
and essential tremor. It is less commonly used or is under investigation for other disorders, such as
epilepsy, Tourette’s syndrome (TS), depression, and obsessive compulsive disorder, amongst other
disorders.
What is DBS?
The procedure involves delivering targeted electrical stimulation to specific brain regions, using
permanently placed small electrodes to alleviate the symptoms of the disorder being treated.
DBS is a neurosurgical procedure where stimulation electrodes are implanted into specific regions of the
brain and receive continuous electrical stimulation by an impulse generator, which is implanted in the
upper chest under the collarbone and connected to the electrodes under the skin by cables (leads). The
pulse generator is also referred to as an ‘internal neural stimulator’ or ‘brain pacemaker’ (Coenen et al,
2015), and has a battery life of 1-5 years for those with externally chargeable batteries.
After the patient has recovered from surgery, the impulse generator is turned on and various stimulation
parameters (including voltage, pulse width and frequency) are adjusted to receive the optimal response
to treat the symptoms of the disorder. The level of stimulation is individualised to the clinical
requirements of each patient and the disorder being treated.
Clinical Indications
DBS is a well-established treatment for movement disorders such as Parkinson’s disease, tremor and
dystonia in Australia and other countries. The use of DBS to treat movement disorders has been
approved in the UK by the National Institute of Clinical Excellence and in the US by the Food and Drug
Administration, although in the US it is also approved for the treatment of OCD. In Australia, the DBS
procedure for the treatment of Parkinson’s disease is eligible for reimbursement under the Medicare
Benefits Schedule however there may be considerable out-of-pocket costs. The DBS procedure for other
psychiatric or neurological disorders is not eligible for reimbursement.
RANZCP Fellows are currently conducting a randomised, controlled trial of DBS for severe treatment
resistant OCD at St Andrew's War Memorial Hospital in Brisbane. An independent mental health review
tribunal determines patient candidacy for the trial and those under the age of 18 are excluded.
Anecdotal evidence from RANZCP Fellows concur that it is extremely rare for children or adolescents to
be treated for any type of disorder using DBS and there are no scientific reports of DBS being
undertaken for psychiatric disorders in children under 16. DBS is not currently used in Australia as a
means to treat children or adolescents.
A review of current literature on DBS for psychiatric disorders displays a mix of criticism and cautious
optimism for the treatment, but agree that a stronger clinical evidence base of randomised control trials
is necessary to identify the procedure’s efficacy and safety. Coenen et al (2015) describes the use of
DBS in the treatment of psychiatric disorders, such as depression, substance abuse and schizophrenia
as ‘experimental’. Kiseley et al (2014) also states that DBS is an intervention that should be considered
an experimental treatment in adults with severe, medically refractory psychiatric disorders. Fitzgerald &
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Segrave, (2015) comment that whilst there is promising initial data to support the efficacy of DBS as a
form of treatment for psychiatric disorders, there is insufficient evidence at present to support the use of
DBS as a clinical treatment for psychiatric disorders outside of research and clinical trials.
Whilst Mosley et al (2015) describe how DBS may be an option for patients suffering from the most
severe forms of intractable depression, as many patients suffer from residual depressive symptoms that
fail to remit with existing biological and psychological therapies. Also, RANZCP Fellows are aware it has
been argued that there is sufficient preliminary evidence to make DBS available for adult patients with
highly treatment resistant OCD, this is evident in its use and approval in the US by the Food and Drug
Administration.
Adverse Effects
In terms of adverse effects, there are mainly two types of concerns associated with DBS, those directly
related to the surgical procedure and the implanted device hardware, and those that are a result of the
electrical stimulation.
As with any surgical procedure, there are potential side effects. The adverse effects related to the
surgical procedure include haemorrhage (1-2% of procedures), seizure induction (less than 1% usually
in the first 24 hours), infection (2-3% usually superficial) and other general surgical or anaesthetic
complications (Fitzgerald & Segrave, 2015). With regards to the implanted hardware device, adverse
effects include hardware malfunctioning or cables breaking, however with advances in device technology
the authors suggest these affects are likely to become uncommon.
Research indicates that the side effects of electrical stimulation differ and depend upon which disorder is
being treated and then which targets of the brain are being stimulated. For instance, Fraint and Pal
(2015) describe a range of side effects to electrical stimulation including: changes in sexual behaviour,
weight loss, psychiatric symptoms (e.g. psychosis, depression and hypomania), nausea, vertigo, anxiety,
agitation, euphoria, panic, fear and worsening depression.
Due to the ‘trial and error’ style of searching for optimal stimulation settings, the side effects may be
fleeting and reversible via adjustment of the stimulators, or may be stopped by ceasing the stimulation
altogether (Fitzgerald and Segrave, 2015).
An example of the success and side effects of DBS in a psychiatric disorder is Kiseley et al’s (2014)
meta-analysis of 5 studies of DBS for severe treatment resistant OCD patients (only 5 studies met the
meta-analysis criteria). The main outcome of the analysis was a significant reduction in obsessive
symptoms indicated by the pooled reduction in Yale–Brown Obsessive Compulsive Scale score of 9
points (scale out of 40). However one third of patients experienced serious adverse effects (including
haemorrhage, hypomanic symptoms, forgetfulness, increased libido, paraesthesias).
Patient Selection and Consent
Due to the invasiveness of the DBS procedure the screening and selection of candidates is essential
and most importantly be reserved for patients who have a severe treatment resistant disorder, and by
most definitions this requires many years of illness (e.g. 5 years). This should be conducted ideally by a
multidisciplinary team that includes a specialist neurosurgeon and a psychiatrist or neurologist
depending on the indicated use, all with appropriate training and expertise in DBS.
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Generally, agreed guidelines exist for patient selection for DBS for movement disorders, yet there are
not necessarily guidelines for DBS for other neurological or psychiatric disorders. For instance, Fraint
and Pal (2015) point out that there are no universally accepted guidelines defining ideal DBS candidates
for Tourette’s syndrome. Although important factors to consider are age, tic severity and treatment
refractoriness.
A review of the literature shows that important factors for the screening and selection of candidates for
DBS include the candidate’s age (how it relates to the disorder), severity of the disorder, treatment
refractoriness, and presence of psychiatric symptoms. If the patient has a history of psychosis or
depression then post-operative monitoring of these symptoms is essential (Ashkan et al, 2013).
Due to the complexities of undertaking a DBS procedure, informed patient consent is necessary for
patients considering DBS and should be required in legislation controlling access to this procedure. The
procedure is not suitable for use as an involuntary intervention.
Due to the lack of clinical evidence of the effectiveness or safety of DBS for treating children or
adolescents with psychiatric disorders, use in this population should be considered highly experimental.
It is recommended that this age group should not be considered for this treatment at this time except in
an ethically approved and appropriately regulated clinical trial. Consideration of the procedure in
exceptional circumstances should be via a legally mandated review process. It is suggested that in
Queensland this could occur through either the Mental Health Review Tribunal or the Family Court
(which has provision for decision making that is in the best interests of the child or adolescent).
DBS Administration
The DBS procedure should ideally be conducted by a multidisciplinary team that includes a
neurosurgeon and a psychiatrist or neurologist depending on the indicated use with appropriate training
and expertise in DBS, and be located at a hospital or clinic that is experienced in carrying out the
procedure.
In Queensland, the Movement Disorders Clinic at St Andrews War Memorial Hospital in Brisbane carries
out DBS for patients with movement disorders and severe treatment resistant TS. It is the only hospital
or clinic that conducts the DBS procedure to treat psychiatric disorders in Queensland.
New South Wales and the Northern Territory are the only state and territory to ban the DBS procedure to
treat psychiatric disorders, yet not neurological disorders. Although this has been criticised for limiting
patients’ equality of access to health care which is a fundamental element of the right to health (Loo et
al, 2010).
Future Directions
There appears to be great scope and enthusiasm worldwide for the use of DBS to treat psychiatric
disorders, yet further research and clinical trials are required to develop a substantial body evidence to
support its efficacy and safety, particularly for child and adolescent patients.
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References
Ashkan K., Shotbolt P., Anthony D. & Samuel M. (2013) Deep brain stimulation: a return journey from
psychiatry to neurology. Postgraduate Medical Journal 89: 323-328.
Coenen V. A., Amtage F., Volkmann J. & Schläpfer T. E. (2015) Deep brain stimulation in neurological
and psychiatric disorders. Deutsches Ärtzeblatt International 112: 519-26.
Fitzgerald P. B. & Segrave R. A. (2015) Deep brain stimulation in mental health: Review of evidence for
clinical efficacy. Australian & New Zealand Journal of Psychiatry 49(11): 979-993.
Fraint A. & Pal G. (2015) Deep brain stimulation in Tourette’s syndrome. Frontiers in Neurology 6(170):
1-7.
Kiseley S., Hall K., Siskind D., Frater J., Olson S. & Crompton D. (2014) Deep brain stimulation in
obsessive compulsive disorder a systematic review and meta-analysis. Psychological Medicine 44:
3533-3542.
Loo C., Trollor J., Alonzo A., Rendina N. & Kavess R. (2010) Mental health legislation and psychiatric
treatments in NSW: electroconvulsive therapy and deep brain stimulation. Australasian Psychiatry 18(5):
417-425.
Mosley P., Marsh R. & Carter A. (2015) Deep brain stimulation for depression: Scientific issues and
future directions. Australian & New Zealand Journal of Psychiatry 49(11): 967-978.
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