On this page:
- DALYs and health expectancy
- How we can use the NZBD
- The NZBD and the Global Burden of Disease Study
- NZBD reports
- Key findings
The New Zealand Burden of Diseases, Injuries and Risk Factors Study, 2006–2016 (NZBD) analyses health losses sustained by New Zealanders of all ages, both sexes and both major ethnic groups.
Health loss (or burden of disease) measures how much healthy life is lost due to premature death, illness or impairment.
The NZBD includes estimates for 2006 and projections to 2016 of both fatal and non-fatal health losses. It assesses health loss from a comprehensive set of 217 diseases and injuries and 31 behavioural and biological risk factors.
The NZBD uses two summary measures of population health: disability-adjusted life years (DALYs) and health expectancy. DALYs integrate fatal and non-fatal impacts to measure health loss. Health expectancy is a generalisation of life expectancy to include both survival and the relative healthiness of the years lived by the population.
The information provided by the NZBD should be of value to policy makers, funders, health planners, researchers and interested citizens.
It allows us to see the magnitude and distribution of causes of health loss for each demographic group and helps us compare the relative impacts of different diseases, injuries and risk factors on health. Understanding how much different risk factors contribute to health loss is particularly important from the perspective of prevention.
In short, health loss information provides evidence on the health impacts of different diseases, injuries and risk factors. The health loss data can be used along with other evidence, including the costs and effectiveness of interventions (health services), to inform decisions on resource allocation, priority setting and investment in health services and prevention programmes.
We can also use the NZBD to compare health expectancy with full life expectancy to see whether our health system is succeeding in adding ‘life to years’ as well as ‘years to life’ – whether people are not only living longer but also living longer in good health. This question is becoming increasingly critical as we enter a period of rapid population ageing with its accompanying rise in long-term conditions and disability.
The Global Burden of Disease Study 2010 is a major global study led by the University of Washington and published in The Lancet in December 2012.
The NZBD is independent of the Global Burden of Disease Study 2010. The two studies use different data sources and methods, yet are still reasonably comparable. So the Global Burden of Disease Study 2010 can be used to provide estimates of historical trends in health loss for New Zealand from 1990 to 2010, and can also help benchmark New Zealand’s performance against peer group countries.
The NZBD includes the following three reports and a statistical annexe (other reports will follow later):
- Health Loss in New Zealand: A report from the New Zealand Burden of Diseases, Injuries and Risk Factors Study 2006–2016 summarises the key findings, objectives and methods of the NZBD and discusses implications for policy and monitoring
- Injury-related Health Loss: A report from the New Zealand Burden of Diseases, Injuries and Risk Factors Study, 2006-2016 is published jointly by the Ministry and the Accident Compensation Corporation. This report provides more detailed methods and results for intentional and unintentional injuries
- Ways and Means: A report on methodology from the New Zealand Burden of Disease, Injury and Risk Study, 2006 - 2016 provides more detail about the data sources and statistical and epidemiological methods used in the NZBD
- New Zealand Burden of Diseases Statistical Annexe is a series of excel pivot tables, providing the full results from the study. This includes estimates and projections of fatal, non-fatal and integrated health losses by age, sex and ethnicity for all disease, injury and risk factor causes, and estimates and projections of health expectancy. Both point estimates and standard errors are provided.
The NZBD includes a wealth of detail, but the key findings are listed below.
- In 2006, New Zealanders sustained health loss totalling almost one million years of healthy life (955,000 DALYs). Just over half (51%) of this total health loss resulted from fatal outcomes.
- Older people (65+ years) sustained over one-third (37%) of the total health loss despite making up only 12% of the population.
- Adjusting for age, males experienced 55% more fatal health loss than females but a lighter burden of non-fatal health loss (16% less).
- Adjusting for age and population size, health loss in Māori was almost 1.8 times higher than in non-Māori, with more than half of Māori health loss occurring before middle age.
- All-cause DALYs lost are projected to increase from 955,000 in 2006 to 1.085 million in 2016, a rise of 13.4%. Demographic changes explain 80% of this trend, while epidemiological changes explain the remaining 20%.
- In 2006, cancers (17.5%) and vascular and blood disorders (17.5%) were the leading causes of health loss at the condition group level, followed by mental disorders (11%), musculoskeletal disorders (9%) and injury (8%).
- Different conditions contribute to health loss at different life stages, with the leading condition groups as follows:
- childhood (0–14 years): infant conditions and birth defects (49% of health loss in this age group)
- youth (15–24 years): mental disorders (31%) and injury (27%), with reproductive disorders also important for females
- young adults (25–44 years): mental disorders (25%) and injury (15%), with reproductive disorders also important for females
- middle age (45–64 years): the well-known chronic diseases of cancers (24%) and vascular disorders (16%) start to come to prominence
- older adults aged 65–74 years: cancers (29%) and vascular disorders (24%) remain leading causes of health loss, followed by musculoskeletal conditions (11%)
- older adults aged 75 years and over: vascular disorders (35%) overtake cancers (18%) as the leading cause of health loss, with neurological conditions ranked third (10%).
- Māori sustain greater health loss in most condition groups. On an absolute scale, 26% of the excess burden experienced by Māori was caused by vascular disorders, 15% by cancers, 12% by mental illness, 11% by injury, and 9% by diabetes and other endocrine disorders.
- The leading causes of health loss at the condition group level are projected to remain the same from 2006 to 2016.
- Coronary heart disease was the leading cause of health loss in 2006 (9.3%), followed by anxiety and depressive disorders (5.3%), stroke (3.9%), chronic obstructive pulmonary disease (COPD, 3.7%), diabetes (3.0%), lung cancer (3.0%), back disorders (2.8%), bowel cancer (2.5%), traumatic brain injury (2.3%) and osteoarthritis (2.2%).
- Leading specific causes differed by sex. Among males, coronary heart disease was ranked first and anxiety and depressive disorders second. This order was reversed among females. Other major sex differences included a higher ranking of back disorders and osteoarthritis among females, and of alcohol use disorders among males.
- Leading specific conditions varied over the life cycle, as follows:
- childhood (0–14 years): complications of premature birth (10.3%), intrapartum stillbirth (9.3%), and sudden unexplained death in infants (SUDI, 7.4%)
- youth (15–24 years): alcohol use disorders (14.3%), anxiety and depressive disorders (13.6%) and traumatic brain injury (10.8%)
- young adults (25–44 years): anxiety and depressive disorders (12.4%), alcohol use disorders (4.7%) and back disorders (4.6%)
- middle age (45–64 years): coronary heart disease (6.8%), anxiety and depressive disorders (3.8%), lung cancer (3.3%) and diabetes (2.8%)
- older adults aged 65–74 years: coronary heart disease (13.6%), COPD (6.3%), lung cancer (6.1%) and bowel cancer (5.0%)
- older adults aged 75 years and over: coronary heart disease (18.3%), stroke (9.8%), COPD (6.7%) and dementia (6.7%).
- Leading specific conditions were similar for Māori and non-Māori, with some exceptions. For both groups, coronary heart disease was the leading specific condition, followed by anxiety and depressive disorders. Then the rank order differed, with diabetes, lung cancer, traumatic brain injury and alcohol use disorders more highly ranked among Māori.
- Relative inequalities in burden between Māori and non-Māori were highest for rheumatic fever/rheumatic heart disease, viral hepatitis, cardiomyopathies, hypertensive heart disease and bronchiectasis. However, the leading contributors to absolute differences in health loss were coronary heart disease, diabetes, lung cancer and COPD.
- Major health risks jointly accounted for about one-third of health loss in 2006. This proportion is not expected to change by 2016.
- Leading risk factor clusters were physiological risk factors (high blood pressure, high blood cholesterol, high blood glucose and low bone mineral density; 13.7% of DALYs) and substance use (tobacco, alcohol and illicit drugs; 13.7% of DALYs).
- Collectively, dietary risk factors (high salt intake, high saturated fat intake, low vegetable and fruit intake) and excess energy intake (high body mass index, BMI) accounted for 11.4% of health loss.
- Injury risk factors (transportation, falls, mechanical force, drowning, poisoning, fire, animal related, self-inflicted, violence) collectively accounted for 8.0% of health loss.
- Among individual risk factors, tobacco use (9.1%) was the leading risk to health in 2006, followed by high BMI (7.9%).
- Other important risk factor causes of health loss were high blood pressure (6.4%), low physical activity (4.2%), alcohol use (net of protective effects, 3.9%), high blood cholesterol (3.2%) and adverse health care events (3.2%).
- In 2006, males on average could expect to live 78.1 years, with 8.9 years (11%) in poor health, according to the health loss estimates in NZBD.
- In 2006, females could expect to live 82.1 years, with 11.5 years (14%) in poor health.
- Although females could expect to live 4.0 years longer than males in 2006, 2.6 years were years of poor health and only 1.4 years were years in full health.
- Two-thirds of the life years gained over the decade from 2006 to 2016 are projected to be lived in good health.