Report of the New South Wales Chief Health Officer	Table of contents Chapter introduction On this page: Data table Commentary References Print version Downloadable files
	Burden of disease Introduction

In this chapter

• Life expectancy at birth
• Life expectancy at birth by health area
• Life expectancy at 65 years
• Life expectancy at 65 years by health area
• Deaths from all causes
• Deaths from all causes by health area
• Causes of death
• Potentially avoidable deaths with projections
• Avoidable deaths by local government area
• Infant mortality
• Hospitalisations for all causes with projections
• Hospitalisations by health area
• Causes of hospitalisation
• Self-rated health
• Disability adjusted life years in NSW
• Disability adjusted life years and health risk factors
• Ambulatory care sensitive conditions: hospitals separations by category
• Ambulatory care sensitive conditions: hospital separations by condition
• Ambulatory care sensitive conditions: hospital separations by local government area
• General practice workload and ambulatory care sensitive conditions by division of general practice
• Dementia
• Arthritis and other musculoskeletal conditions
• International rankings of life expectancy
• International rankings of infant mortality
• International rankings of overweight and obesity

Introduction

This chapter focuses on trends in life expectancy and death rates in NSW, and examines the major causes of death, hospitalisation and disability. A number of measures are used to shed light on the relative contribution of various diseases, conditions and causes of injury to this loss of life and disability. Traditional indicators, such as life expectancy, infant mortality and self-rated health status are examined first, but some traditional indicators, such as the age-adjusted death and hospitalisation rates had projections added to the trend lines. Then, newer indicators are presented, beginning with indicators which use the global burden of disease approach, from which this chapter takes its name, followed by indicators analysing ambulatory care sensitive conditions. International comparisons of three indicators are presented, including overweight and obesity. Finally, a new indicator on arthritis and other musculoskeletal conditions and another one on dementia complete the chapter.

The concepts of the burden of disease approach and ambulatory care sensitive conditions require further introduction.

The major limitation of using only death and hospitalisation data to assess the burden that particular diseases or causes of injury place on the community is that some conditions which cause substantial suffering or disability but which don't result in death or hospitalisation are overlooked. The global burden of disease approach aims to address these limitations, by using a summary health gap measure called the 'disability adjusted life year' (DALY), and by comprehensively assessing the complete spectrum of disease that occurs in a population.

The DALY aims to quantify the amount of full health lost due to disease or injury occurring in a particular period, by adding the burden arising from deaths in that period to the burden of incident (new) cases of disease or injury occurring in that same period. The burden is not simply the number of cases, but is quantified by multiplying the number of incident cases by an estimate of relative severity of disability caused by the condition, known as the disability weight, and by the duration of the loss of health. The disability weight is measured on a scale of zero to one, and is constructed so that zero means full health and one means death. The duration of loss of health or loss of life is limited by an 'ideal' life expectancy from a life table chosen for each study.

An optional discounting factor to reflect the greater importance people, on average, place on the loss of health in the near future compared with the distant future, can also be incorporated into the calculation. Age-weighting to assign different weights based on the economic and social welfare value of people at different ages can also be incorporated. The methodology used in Australia uses discounting, but not age-weighting, in the measures given in this report.

The DALY for a cause of disease or injury is calculated separately for each age group defined and for each sex. The total burden of that disease is the sum of the DALYs for all age groups and both sexes. This additive feature of DALYs is central to its application to different aggregations and disaggregations of populations and causes of disease or injury.

The study by Begg and colleagues 'The burden of disease and injury in Australia, 2003' (Begg et al., in press) is the second complete assessment of health status of Australian population. The DALY calculated for NSW by the study are presented in this chapter.

Ambulatory care sensitive conditions are those for which hospitalisation is considered potentially avoidable through preventive care and early disease management, usually delivered in an ambulatory setting, such as primary health care (for example by general practitioners or community health centres).

Hospitalisation rates for ambulatory care sensitive conditions are used as an indicator of access to, and quality of, primary care. Other factors that influence rates include disease prevalence in the community, hospital admission and coding practices, and personal choices about seeking health care. The conditions reported here as ambulatory care sensitive are presented in three categories: vaccine-preventable conditions, acute conditions and chronic conditions.

Diabetes with complications, angina, chronic obstructive pulmonary disease, asthma and congestive heart failure usually account for around half of all ambulatory care sensitive hospitalisations in NSW. More information about these conditions can be found in other chapters of this report.

More information on the methods used for calculating life expectancy and age-adjusted death and hospitalisation rates can be found in the Methods section. The values for life expectancy that appear in this report may differ slightly from those published by the Australian Bureau of Statistics due to minor discrepancies in these methods. The ICD-10 and ICD-9 codes used for each indicator are included in the disease and procedure codes appendix.

Top of page

Table of contents