The rate of type 2 diabetes among children in Greater Auckland has shot up five-fold in 13 years, prompting debate on lowering the age for obesity surgery.

Obesity increases a person's risk of developing type 2 diabetes. Eighteen is the lower limit for obesity surgery, which can cure type 2 diabetes.

Type 2 diabetes was traditionally thought of as an adult-onset disease, but it began to emerge in children in the 1990s as the "obesity epidemic" worsened.

Wellington physician Dr Jeremy Krebs said the increased annual incidence detected by the study of referrals to Starship children's hospital was an alarming rise for a relatively short period.


"This study further increases my fear for the future of diabetes in this country. The appearance of type 2 diabetes in children and adolescents highlights the importance of childhood obesity and the need to address this."

The study, published in the international journal Pediatric Diabetes, says Auckland's population incidence of the disease among children was higher than Britain's rate of 0.6 in 100,000, "but in part reflects an exceptionally high risk in Maori and Pacific Islanders".

Dr Craig Jefferies, one of the authors of the study, said yesterday the Auckland rate had peaked in 2003, then reduced to its 2007 level. It had stayed at about the 2007 level since.

The journal article speculates that the 2003 to 2007 reduction may indicate that the "underlying epidemic of obesity may also not be worsening rapidly" and this "may be an early sign of success of intensive public health campaigns for healthy eating".

However, it omits to say that some of the expansion of the Labour Government's Healthy Eating Healthy Action campaign occurred in the latter part of that period, and significant parts of it have since been wound back by National.

The study also found high rates of linked health problems in the diabetic children, including just over half who had high blood pressure and 35 per cent with kidney abnormalities. Dr Jefferies said children with that sort of diabetes profile were likely to suffer significant complications starting in their 20s.

Ninety per cent of the 52 children in the study were of Pacific Island or Maori ethnicity and the age range at referral to the hospital's diabetes clinic was 7 to 15. More than two-thirds had at least one parent with type 2 diabetes.

Dr Jefferies said bariatric surgery needed to be made available at a younger age. Auckland District Health Board surgeon Grant Beban said reducing the lower age limit for surgery was being investigated by the technology assessment committee.