Avoidable epidemic takes toll

By REBECCA WALSH and KATHERINE HOBY

Paul Hofman has a blunt message for overweight New Zealanders who watch television ads about getting more exercise - and wonder vaguely whether they should get off the couch and walk around the block once in a while.

It's a personal gripe, he adds, and probably not all doctors would agree with him.

"But my belief is if exercise doesn't hurt, it's not that good for you. When we're doing it we should be pushing ourselves. A gentle walk, I'm afraid, is not pushing yourself.

"To burn off what we eat, which is energy-dense food, we need to exercise a lot more and a lot harder."

Hofman sees the results of people not taking his advice every day.

As a paediatric endocrinologist (a specialist in hormonal disorders in children) at the Starship children's hospital in Auckland, he is now treating teenagers for diabetes problems previously seen only in the middle-aged and elderly.

He finds the trend deeply worrying, but also frustrating, because diabetes is so avoidable.

As he bluntly puts it: "If you don't get fat and you exercise and have an active lifestyle, you shouldn't get these diseases. They're preventable."

Other experts agree that in the past few years there has been a disturbing increase in heavily-overweight people in their teens and 20s who have been diagnosed with preventable Type 2 diabetes, which used to be known as "mature onset diabetes".

For the patients that means prolonged exposure to the disease and the risk of complications at an earlier age. For the country, it is an economic drag on the health system.

And if Type 2 diabetes goes unchecked, the results can be even more dramatic. Worst-case scenarios include renal failure, blindness, impotence, limb amputation and death. The Ministry of Health estimates at least 1500 New Zealanders die of diabetes-related illnesses each year.

The main cause of the epidemic (as it is officially described by health agencies) is that, as a nation, we are getting too fat through poor diet and lack of exercise.

Three out of 10 New Zealanders are expected to be officially obese within a decade - almost double the present level.

Much of this increase is driven by our rapidly changing ethnic make-up.

Pacific Islanders, Maori and Asians (all growing as a percentage of New Zealand's population) are far more likely to develop diabetes than Europeans for a combination of genetic and lifestyle reasons.

The epidemic's long-term effect on the health system is expected to be dramatic.

The estimated cost of diabetes to the taxpayer - mostly spent on diabetes-related complications - is $170 million each year.

But an extensive report by PricewaterhouseCoopers, commissioned by Diabetes New Zealand in 2000, suggests the cost could skyrocket to more than $1 billion a year by 2021.

Put another way, diabetes spending will soar from 2 per cent to 12 per cent of health expenditure in under 20 years,

Diabetes New Zealand president Ross Finnerty argues the true cost could be even higher, as the report ignored blindness, heart disease and renal failure, which are often caused by diabetes.

About 115,000 people are known to have diabetes in New Zealand. As many are thought to have it but do not know.

Even if there is no improvement in our obesity levels, diet and exercise, a further 60,000 people are expected to be diagnosed with Type 2 diabetes in the next 20 years.

The Health Ministry predicts diabetes will jump 50 per cent for Europeans (from 3.1 to 4.5 per cent of the population) and will at least double for Maori and Pacific Islanders (from 8 to about 16 per cent).

In other words, by 2020 about one in six Maori and Pacific Island adults will have diabetes.

The epidemic is part of a global problem.

The World Health Organisation estimates that if trends continue, the number of people with diabetes will more than double, from 140 million to 300 million, in 25 years.

Diabetes is a metabolic disorder where the body is unable to control the amount of glucose in the blood. In most people, insulin, a natural hormone produced by the pancreas, helps move glucose from food out of the bloodstream and into the body cells.

Once glucose has been moved into the cells it can be burned as energy, or stored as future energy.

But in Type 2 diabetes, which makes up 90 per cent of cases, the body does not produce enough insulin or use the insulin it does produce in a healthy way.

In many cases, Type 2 diabetes can be prevented or better managed through a healthy lifestyle.

In contrast, Type 1 diabetes - an "auto-immune condition" where the body attacks the cells within it that make insulin - is not preventable and people with it become insulin dependent.

For some people, managing their diabetes is a matter of changing the foods they eat, losing weight and exercising.

Others must constantly monitor their blood sugar levels and inject themselves with insulin every day.

Dr Robyn Toomath, president of the Society for the Study of Diabetes and spokeswoman for Foe (Fight the Obesity Epidemic), says about 80 to 90 per cent of people with Type 2 diabetes are obese and being very overweight increases the chances of developing diabetes 40 to 80 times.

"If you don't carry the gene for diabetes you can be hugely overweight and never become diabetic," she explains.

"If you do carry the genetic material for diabetes you probably won't become diabetic unless you become overweight, particularly around the middle."

Dr Toomath, an endocrinologist at Wellington Hospital, says the problem stems from fat in the abdominal cavity. This contains a hormone that contributes to the insulin resistance which causes diabetes.

Men with a waist measurement of 100cm and women with a measurement of 90cm or more are at risk.

Dr Toomath says although no figures are kept on childhood obesity levels, anecdotal evidence here and overseas suggests children are getting fatter more quickly than other age groups.

Children are less likely to bike or walk to school and many spend hours in front of television or computers. Junk food is a major feature of their diet.

Toomath and her anti-fat group are working with Labour MP Tim Barnett on a private member's bill to get advertising for junk food banned from children's TV and to remove junk food from school tuck shops.

"It's an absolute affront to have young children bombarded with hours of advertising telling them to consume fast foods while they are sitting on their bums watching television," she says.

As diabetes rates are so much higher among non-Europeans, researchers have been asking whether this is the result of ethnic differences or changed lifestyle in Western countries.

While the answer remains unclear, the consensus seems to be a bit of both.

Auckland University of Technology physiologist Dr Elaine Rush has conducted research showing Indian people living in New Zealand have more internal abdominal fat than Pacific Islanders or Maori, and much more than Europeans.

"Those from some Asian cultures who have more of a 'natural risk' already, if you put them in an environment where their lifestyle is likely to change dramatically, then they are certainly at high risk of developing it."

Government statistics predict the number of Asians in New Zealand will almost double to 370,000, or 9 per cent of the population, by 2016.

However, Rush cautions that the "Asian" label is too vague - some ethnic groups have higher risks than others.

Maori and Pacific Islanders are three times more likely to develop diabetes than Pakeha. However, this may not be solely genetic either. Obesity tends to be more of an issue among lower socio-economic communities, where Maori and Pacific people are over-represented.

Deidre Cameron, the nurse in charge of the diabetes project at Health Pacifica, a primary care practice based in Mangere, says the traditional outdoor life many Pacific Islanders enjoyed is often replaced by a less active one in New Zealand.

At the same time fastfood outlets are more prevalent and well utilised - "those on higher incomes can be more selective about the restaurants and cafes they go to".

Foods seen as a delicacy in the islands, such as tinned corned beef, which is high in salt and fat, are more readily available, as are favourites such as mutton flaps. It doesn't help when basics such as milk cost more than soft drinks.

Figures for the Counties-Manukau area show Pacific Islanders comprised 22 per cent of the district health board's population but the prevalence of diabetes was five times that of other ethnic groups.

Ms Cameron says diabetes complications account for 17 per cent of Pacific Island deaths compared to 4 per cent of deaths for people with a European background. High rates of obesity, inconsistent disease management and the fact Pacific people tended to develop diabetes about 10 years younger than the rest of the population are contributing factors, she says.

Tony Haas, president of Retina New Zealand, which is strongly behind the diabetes awareness campaign, says some Pacific Islanders, through poverty or habit, eat a lot of foods that are not good for them.

"Some of the less healthy traditional habits are fostered too strongly by Pacific leaders," he says. "They need to think about the future health of their families and friends."

Further reading
nzherald.co.nz/health