Causes of death in New Zealand
02 April 2004
Looking Upstream - causes of death by risk and condition in New Zealand
A report identifying the top 20 causes of death in New Zealand, classified by risk factor as well as by health condition (disease or injury), has been released today by the Ministry of Health.
It is the first time such a comprehensive mortality analysis has been done, attributing mortality to a wide range of risk factors. Previous studies have looked only at a small number of risk factors, such as tobacco use, nutrition or injury.
The report's author, Dr Martin Tobias, from the Ministry's Public Health Intelligence Unit, says "The objective is to provide a planning tool for disease prevention and health promotion at national and district levels."
Dr Tobias says "Much of the information is already available, but the report brings it together and also provides a more consistent way to classify causes of death at risk factor level. "
Risk factors are classified into behavioural, biological, environmental and social categories.
Behavioural factors include diet, physical activity, drug use, and injury. Diet and insufficient physical activity are estimated to have been responsible for approximately 11,000 deaths in 1997, almost 40 per cent of all deaths in that year.
Among the biological risk factors, which largely overlap with the behavioural risk and protective factors, it is estimated that elevated blood cholesterol accounted for 4,700 deaths. High blood pressure is estimated to have been responsible for approximately 3,700 deaths, and elevated body mass index (weight adjusted for height) for approximately 3200 deaths. If more New Zealanders enjoyed a healthy diet (according to New Zealand guidelines) and active lifestyle (at least 30 minutes of moderate intensity activity on 5 or more days of the week), hundreds of deaths could be prevented each year.
In the environmental risks category, air pollution has been identified as a major cause of death with approximately 970 deaths in 1997, and it has been estimated that 40% of those reflect vehicle emissions. Occupational diseases and injuries are estimated to have accounted for at least 190 deaths in that year.
Dr Douglas Lush, the Ministry's Acting Director of Public Health, comments "The report should help policy-makers and planners identify which risk and protective factors are worthy of more attention. Coupled with information on the effectiveness and cost of different interventions, this approach of classifying causes of death at risk factor as well as condition level can contribute to evidence based decisions regarding health promotion and disease prevention interventions."
"It is important, however, not to focus solely on risk factors in isolation. Risk factors overlap and interact in complex ways, and are shaped to some extent by social forces, such as whether individuals can afford a healthy diet."