Coeliac disease far more common than thought

19 May 2014

Coeliac disease far more common than thought

New Zealand and Australian volunteers help to reshape coeliac disease worldwide

A recent Australian population study has revealed that coeliac disease is 40% more prevalent in Australian women and 25% more prevalent in Australian men than previously thought.

Conducted in 2013 the research also reveals coeliac disease is one of the most underdiagnosed illnesses in Australia – only 1 in 5 coeliacs know they have the condition.

New Zealand-born and trained gastroenterologist Dr Bob Anderson was involved in the Australian study and says that based on this Australian study, and assuming the prevalence of coeliac disease is similar in New Zealand, then it would be expected that almost 65,000 Kiwis may have the disease.

The study discovered these findings by combining traditional antibody testing (measuring the immune response to gluten) with an assessment of specific genetic risk markers for coeliac disease among 2500 Australians. It found more than half of Australians had genetic risk factors for developing coeliac disease.

Dr Jason Tye-Din from the Immunology division at the Walter and Eliza Hall Institute worked with Dr Bob Anderson, Barwon Health, DeakinUniversity, Healthscope Pathology and the University of Queensland Diamantina Institute to develop and trial the new diagnostic approach to the disease.

Dr Tye-Din said this new approach of combining the genetic test with a panel of antibody tests would increase the accuracy of testing, decrease overall medical costs by reducing invasive diagnostic tests, and avoid medically unnecessary use of a gluten-free diet.

Coeliac disease is caused by an inappropriate immune response to dietary gluten. Gluten can be found in wheat, rye, barley and oats. When gluten is consumed, it can cause a wide range of complaints from chronic tiredness, iron deficiency, osteoporosis, itchy rash, and headaches to various digestive symptoms. Coeliac disease damages the lining of the small intestine and can lead to significant medical complications such as autoimmune disease, infertility, liver failure and cancer. Coeliac disease usually develops in childhood and is life-long, but early diagnosis and treatment can reduce the risk of adverse health complications.

“Currently, bowel biopsies are recommended for anybody with positive antibody tests,” Dr Tye-Din said.

“In this study the inclusion of a simple genetic test helped identify a substantial number of people whose antibody tests were falsely positive and who did not actually require a bowel biopsy to test for the possibility of coeliac disease.

“Accurate and timely diagnosis is important for the health of patients with coeliac disease. Making a diagnosis based on a blood test alone or commencing a gluten- free diet without a confirmatory bowel biopsy is inappropriate and can impose an unnecessary and lifelong treatment.

“Although a small bowel biopsy is needed to confirm coeliac disease it is costly and invasive. Reducing unnecessary procedures is better for patients, eliminating an invasive test, and better for the economy by reducing healthcare costs,” Dr Tye-Din said.

“This study provides a strategy to improve the diagnosis of coeliac disease in the community by combining the benefits of antibody and genetic testing,” he said.

Coeliac New Zealand’s Coeliac Awareness Week kicks off on May 19 this year with the aim of increasing understanding of the disease among New Zealanders and the medical fraternity.

President of Coeliac New Zealand, Terry Hoskins, says that valuable research like this highlights the need for greater awareness of this often misunderstood condition.

“We urge health professionals to be mindful of the symptoms of coeliacdisease and refer patients for testing via a simple blood test when symptoms present,” Terry says.

“So many new cases of coeliac disease go unnoticed each year because the symptoms and diagnose of the disease are not clear cut.

“Thousands of people go to their GP each year because they feel sick and tired,” says Terry.

“Being sick and tired are symptoms of so many possible conditions as well as of our ever-increasing, busy lifestyles.

“However, if someone has been this way for a long time and is plain sick and tired of feeling sick and tired then we would encourage them to ask their GP for further investigations to be done,” Terry says.

Professor Andrew Day, Paediatric Gastroenterologist, in Christchurch NZ echoes these concerns. “Although diagnosis can be straight forward for some young people, in others it can be delayed, with symptoms for a prolonged period of time, says Dr Day.

“Prompt recognition of the possibility of coeliac disease, with early diagnosis can make a huge difference in the lives of patients”.

Two groups of medically-confirmed coeliac sufferers based in Auckland and Canterbury are currently volunteering in an international study which is conducting clinical trials of a new vaccine, Nexvax2, which aims to restores tolerance to gluten.

The New Zealand study is being run by Dr Chris Wynne at the Christchurch Clinical Studies Trust and will ensure that an increased focus on understanding and treating coeliac disease will continue.

Coeliac New Zealand
Coeliac New Zealand, a national non-profit organisation based in Auckland. It supports those with coeliac disease, dermatitis herpetiformis and those on a gluten-free diet through education and collaboration with gluten free manufacturers, medical professionals and supports research. Coeliac New Zealand was established in 1973. www.coeliac.org.nz | www.facebook.com/CoeliacNewZealand

ENDS

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