EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (EXTEND45)

Chronic kidney disease (CKD) and diabetes are major causes of death and morbidity worldwide and are associated with high health service utilisation persisting over many years. Their slow progression and wide clinical variation make them highly suitable for study in population-based cohorts. However, current understanding of their prevalence, incidence and progression is largely based on studies conducted in clinical populations.

Aim:

To establish a novel link between an existing population-based cohort (the 45 and Up Study) and routinely-collected laboratory and administrative data to facilitate research across the full disease spectrum of CKD and diabetes.

Research Methodology:

In the EXTEND45 Study, more than 260,000 participants of the New South Wales (NSW)-based 45 and Up Study have been linked to data from laboratory service providers as well as national- and state-based administrative datasets. These datasets include Service Australia’s Medicare Benefits Schedule and Pharmaceutical Benefits Scheme, the NSW Admitted Patient Data Collection, and several more. Data linkage has been performed via best practice methodologies at the Centre for Health Record Linkage (CHeReL) and under strict confidentiality and privacy guidelines.

The wealth of data in the EXTEND45 dataset provides a unique opportunity to examine a broad range of clinical and public health questions relating to CKD and diabetes. Initial research objectives include:

  1. Determine the prevalence and incidence of CKD in the 45 and Up Study cohort and define a seminal CKD cohort that can be used in future studies;
  2. Determine the prevalence and incidence of diabetes in the 45 and Up Study cohort and define a seminal diabetes cohort that can be used in future studies;
  3. Determine the prevalence and incidence of CKD in individuals identified as having diabetes in the 45 and Up Study cohort (see link in Further Reading section below);
  4. Identify risk factors for CKD and diabetes in the community;
  5. Examine the real-world management of these diseases, including prescribing patterns, and identify evidence-practice gaps in the care of individuals with CKD, diabetes, or both, particularly in relation to CVD prevention; and
  6. Evaluate the attainment of clinical targets in the community, identify risk factors for nonattainment, and assess associated health outcomes.

Current Status:

The cohort is active. Follow-up via linked routinely-collected data is ongoing.

List of publications include:

  1. Celine Foote et al. EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (the EXTEND45 Study): Protocol for an Australian Linked Cohort Study. JMIR Res Protoc 2020;9(4):e15646. DOI: 10.2196/15646
  2. Louisa Sukkar et al. Incidence and Associations of Chronic Kidney Disease in Community Participants With Diabetes: A 5-Year Prospective Analysis of the EXTEND45 Study. Diabetes Care Mar 2020, dc191803; DOI: 10.2337/dc19-180