In common with virtually all industrialized countries and many less developed nations, Australia is facing rapid population ageing. Historical patterns of fertility and migration, along with changes in life expectancy, mean that the over 65 age group is likely to increase by around 50% in the next 15–20 years.1 The further increase in the proportion of people in the very old age groups will result in the ‘ageing of the aged’. The challenges presented by the ageing of the population are far reaching. Discussions have tended to focus on its likely health and economic consequences; however, few aspects of society will remain unaffected by the issue.
There is an urgent need for reliable evidence to inform policy to support healthy ageing. The concept of healthy ageing encompasses traditional ideas relating to freedom from disease, as well as broader considerations including independence, quality of life, management of disability, participation in society and the workforce and productivity. A wide range of factors are likely to affect health in later life, including socioeconomic, environmental and cultural variables, cigarette smoking, alcohol consumption, diet, physical activity, reproductive and hormonal factors, infections, availability of healthcare and use of pharmaceutical agents, as well as individuals’ susceptibility to disease. A comprehensive investigation of the determinants of healthy ageing must incorporate assessment of disease risk, quality of life and other indices, in relation to a very wide range of possible exposures, and with consideration of how these exposures might interact with one another. Research needs to be of a sufficient scale to provide specific information on the major diseases and health problems experienced in later life. This is because reliable assessments of risk factor–disease relationships require a substantial degree of pathological homogeneity of outcome and appropriate consideration of confounding. At the same time, research needs to be able to assess the broad risks and benefits of particular exposures, to allow meaningful conclusions to be reached about suitable public health interventions. Finally, it needs to be large and long term enough to track the impact of health interventions and policies at the population level.
Australia has some unique characteristics that will impact on healthy ageing and provide particular challenges in delivering health care. For example, it has: a relatively heterogenous population with a large migrant community; an indigenous population with an average life expectancy 17 years less than for non-indigenous Australians; some remote and sparsely populated regions and a mixed health care system with responsibility shared between the national and state governments and delivery in both the public and private sectors. Excellent population-level databases relating to use of health services and medications, and registers of cancers and deaths, are available for statistical linkage with research data sets. There is therefore a need for research that addresses issues specific to the Australian population and makes use of the unique features of the Australian setting, giving the opportunity to provide insights of international relevance.
The 45 and Up Study was conceived as a long-term collaborative resource to investigate healthy ageing, in response to the gaps in existing knowledge and the needs of researchers.
Initial discussions among interested researchers resulted in the formation of a Scientific Steering Group in 2003 to oversee the development of the Study. The Study is auspiced by the Sax Institute, which also provided funding for its development. The Sax Institute is an independent organization with core funding from the state government of New South Wales, Australia's most populous state. Its mission is to improve health through facilitating high-quality research and increasing the impact of this research on health policy and services; it has membership from public health and health service research centres and universities across New South Wales. Workshops, meetings and consultations with individual researchers were held to identify research priorities for the Study and researchers were invited to become 45 and Up Study Collaborators. There were 120 collaborators at the time of writing (see www.45andUp.org.au for details). The protocol for the Study was completed in late 2003, the Scientific Director was appointed in 2003, the Study materials, methods and governance framework were developed in 2004 and 2005 and recruitment of participants started early in 2006.
Following international peer review of the Study protocol, funding for the Study infrastructure was provided by Foundation Study Partners, The Cancer Council New South Wales, the New South Wales Division of the National Heart Foundation of Australia and the New South Wales Department of Health. These were later joined by beyondblue: the national depression initiative, the New South Wales Department of Ageing, Disability and Home Care, with additional support from the Macquarie Bank Foundation, the Baxter Charitable Foundation, the Alma Hazel Eddy Trust and Freehills solicitors. Competitive funding for a range of research projects has been secured and researchers using Study data for their projects support the Study through contributions to cost recovery and Study sustainability.