Prader-Willi Syndrome and genetic obesity

This specialist clinic for adolescents and adults with Prader-Willi syndrome (PWS) is held in the outpatient Department at Hammersmith Hospital monthly by Dr Tony Goldstone, Consultant Adult Endocrinologist, Imperial College Healthcare NHS Trust. The clinic is run in conjunction with the Paediatric PWS clinic at Chelsea and Westminster Hospital led by Dr Nicola Bridges, Consultant Paediatric Endocrinologist. Other adult patients with confirmed or suspected non-PWS genetic or syndromal causes of obesity may also be referred to this clinic.

The aims of the clinic are to:

• Support transition from Paediatric PWS services

• Reduce the number of hospital visits for the patient and family by combining care in a multidisciplinary clinic

• Allow all families to access medical support specific to PWS with the aim of reducing long term medical complications

• Arrange appropriate tests for hypopituitarism including GH and cortisol deficiency in a specialist centre

• Initiate and monitor GH replacement therapy as indicated (using NICE guidelines)

• Monitor body weight

• Give dietetic, exercise and psychological advice tailored to the individual

• Co-ordinate care with other professionals and provide information

• Screen for and manage complications of obesity such as diabetes mellitus, cardiovascular and respiratory disease in conjunction with local diabetic, dietetic and medicine services

• Liaise with sleep physicians to screen for and treat sleep-disordered breathing

• Identify patients with potential psychiatric or psychological problems that warrant specialist referral or review

• Act as advocates for patients with PWS

• Facilitate clinical research into treatments for PWS particularly regarding obesity and endocrine disorders

The patient and family will be seen together in clinic. The aim is to review patients in transition from the Paediatric PWS clinic at Chelsea and Westminster Hospital (and other Paediatric endocrine services) from the age of 16 years, and adults with PWS approximately every 3-4 months for review. In-patient and day case endocrine, metabolic and other clinical investigations are available on the dedicated Clinical Investigation Ward at the Hammersmith Hospital.

The clinic aims to provide the following support:

• Regular medical review by Dr Goldstone, an adult endocrinologist with clinical and research experience in PWS, obesity, diabetes, pituitary disease and GH replacement in adults, and Dr Bridges, a paediatric endocrinologist with experience in growth, GH treatment, transition, sex hormone replacement in children with and without PWS.

• The opportunity for patients and families to meet in clinic.

• Dietetic advice specific to PWS through dieticians experienced in management of obesity.

• Link with clinical obesity services where appropriate at Imperial Weight Centre, Charing Cross Hospital

• Links with the respiratory and sleep service in Imperial College Healthcare NHS Trust at Charing Cross Hospital for respiratory review and sleep studies (Dr Andrew Cummin, Respiratory Consultant).

• Links with Clinical Geneticists at Kennedy-Galton Centre, NW Thames Regional Genetic Service, Northwick Park Hospital (Dr. Natalie Canham).

• Further links are being developed with Clinical Psychologists within the Trust and Prof. Tony Holland, Professor of Learning Disability, University of Cambridge to provide psychological and psychiatric input into the multi-disciplinary clinic.

• Interpreters are available for those families for whom English is not well understood or spoken, important given the ethnic mix of patients in London and SE England.

Prader-Willi syndrome (PWS) is a complex multi-system genetic disorder that arises from lack of expression of paternally inherited imprinted genes on chromosome 15q11-q13.

The syndrome has characteristic phenotypes (6, 7) including severe neonatal hypotonia; early onset of hyperphagia; and development of morbid obesity, short stature, hypogonadism, learning disabilities, behavioral problems, and psychiatric phenotypes with severe consequences and difficult management issues for patients, families, and care givers.

Adolescents and adults with PWS frequently see multiple different healthcare professions in different hospitals, if at all, in addition to their primary care physicians with specific, specialist input needed for example from endocrine, diabetes, cardiovascular and respiratory services. As individuals with PWS get older they are at risk of increasing obesity with complications such as diabetes, respiratory, sleep, cardiac and psychiatric problems. Quality of life can be reduced by complex medical problems and treatment may be made more difficult because of behaviour patterns and psychological issues specific to PWS. There is currently no treatment to reduce the excessive appetite. However, management which includes intensive supervision of the diet and food environment and exercise to prevent obesity, growth hormone (GH) and sex hormone treatment, follow up for medical complications and psychological support can improve quality of life and reduce medical complications for individuals with PWS.

Most of the healthcare professionals seeing children with PWS will have little experience with this diagnosis, and this is even more so for those seeing adult patients. Patients and families often benefit from the expertise and knowledge of other families and patients who have been through the same problems. In addition, input from professionals with expertise in PWS is needed, and this is especially rue for care of adults with PWS. Particular problems also arise during the transition period from adolescence to adulthood with increased patient autonomy, endocrinological issues around puberty and regarding GH replacement, and continuity of care.

Rcommendations for the Diagnosis and Management of Prader-Willi Syndrome

For referrals to the PWS/genetic obesity clinic at Hammersmith Hospital please send a referral to:

Dr. Tony Goldstone, Consultant Endocrinologist, Hammersmith Hospital, Du Cane Road, London W12 0NN. Tel: 020 3313 4823

The links with obesity services at the Imperial Weight Centre based at Charing Cross Hospital, and the research facilities at Imperial College London and MRC Clinical Sciences Centre on the Hammersmith campus also provides an environment to develop clinical care and research into PWS, genetic causes of obesity and therapies particularly for hyperphagia and obesity.

Dr. Goldstone has researched and published widely on neuroendocrine and metabolic abnormalities in PWS, particularly investigating the causes of hyperphagia and obesity, through clinical, post-mortem, pre-clinical, genetic, interventional, fat and brain imaging studies. He was a member of the Scientific Committee for the 2nd PWS Expert meeting, Toulouse, France in 2006 and the 6th PWS International Conference, Cluj, Romania in 2007, and was Scientific Co-Chair for the 1st International Hyperphagia Conference in Baltimore, USA in 2009. He has been a Vice-President of the UK PWS Association since 2007. He has ongoing clinical and scientific research collaborations with other PWS clinicians worldwide including Prof. Dan Driscoll and Dr. Jennifer Miller, University of Florida, USA; Prof. Tony Holland, University of Cambridge; Prof. Maithe Tauber, University of Toulouse, France.