Costs of major complications in people with and without diabetes in Tasmania, Australia.

Objective We set out to estimate healthcare costs of diabetes complications in the year of first occurrence and the second year, and to quantify the incremental costs of diabetes versus non-diabetes related to each complication. Methods In this cohort study, people with diabetes (n = 45 378) and their age/sex propensity score matched controls (n = 90 756) were identified from a linked dataset in Tasmania, Australia between 2004 and 2017. Direct costs (including hospital, emergency room visits and pathology costs) were calculated from the healthcare system perspective and expressed in 2020 Australian dollars. The average-per-patient costs and the incremental costs in people with diabetes were calculated for each complication. Results First-year costs when the complications occurred were: dialysis $78 152 (95% CI 71 095, 85 858), lower extremity amputations $63 575 (58 290, 68 688), kidney transplant $48 487 (33 862, 68 283), non-fatal myocardial infarction $30 827 (29 558, 32 197), foot ulcer/gangrene $29 803 (27 183, 32 675), ischaemic heart disease $29 160 (26 962, 31 457), non-fatal stroke $27 782 (26 285, 29 354), heart failure $27 379 (25 968, 28 966), kidney failure $24 904 (19 799, 32 557), angina pectoris $18 430 (17 147, 19 791), neuropathy $15 637 (14 265, 17 108), nephropathy $15 133 (12 285, 18 595), retinopathy $14 775 (11 798, 19 199), transient ischaemic attack $13 905 (12 529, 15 536), vitreous hemorrhage $13 405 (10 241, 17 321), and blindness/low vision $12 941 (8164, 19 080). The second-year costs ranged from 16% (ischaemic heart disease) to 74% (dialysis) of first-year costs. Complication costs were 109-275% higher than in people without diabetes. Conclusions Diabetes complications are costly, and the costs are higher in people with diabetes than without diabetes. Our results can be used to populate diabetes simulation models and will support policy analyses to reduce the burden of diabetes.

Development and implementation of a national online application system for cross-jurisdictional linked data.

The Population Health Research Network (PHRN) is an Australian national data linkage infrastructure that links a wide range of health and human services data in privacy-preserving ways. The data linkage infrastructure enables researchers to apply for access to routinely collected, linked, administrative data from the six states and two territories which make up the Commonwealth of Australia, as well as data collected by the Australian Government. The PHRN is a distributed network where data is collected and managed at the respective jurisdictional and/or cross-jurisdictional levels. As a result, access to linked data from multiple jurisdictions requires complex approval processes. This paper describes Australia's approach to enabling access to linked data from multiple jurisdictions. It covers the identification of, and agreement to, a minimum set of data items to be included in a unified national application form, the development and implementation of a national online application system and the harmonisation of business processes for cross-jurisdictional research projects. Utilisation of the online application system and the ongoing challenges of data linkage across jurisdictions are discussed. Changes to the data custodian and ethics committee approval criteria were out of scope for this project.

Incremental healthcare expenditure attributable to diabetes mellitus: A cost of illness study in Tasmania, Australia.

AIMS: To quantify the incremental direct medical costs in people with diabetes from the healthcare system perspective; and to identify trends in the incremental costs. METHODS: This was a matched retrospective cohort study based on a linked data set developed for investigating chronic kidney disease in Tasmania, Australia. Using propensity score matching, 51,324 people with diabetes were matched on age, sex and residential area with 102,648 people without diabetes. Direct medical costs (Australian dollars 2020-2021) due to hospitalisation, Emergency Department visits and pathology tests were included. The incremental costs and cost ratios between mean annual costs of people with diabetes and their controls were calculated. RESULTS: On average, people with diabetes had healthcare costs that were almost double their controls ($2427 [95% CI 2322-2543]; ratio 1.87 [95% CI 1.85-1.91]; pooled from 2007-2017). While in the first year of follow-up, the costs of a person with diabetes were $1643 (95% CI 1489-1806); ratio 1.83 (95% CI 1.76-1.92) more than their control, this increased to $2480 (95% CI 2265-2680); ratio 1.69 (95% CI 1.62-1.77) in the final year. Although the incremental costs were higher in older age groups (e.g., ≥70: $2498 [95% CI 2265-2754]; 40-49: $2117 [95% CI 1887-2384]), the cost ratios were higher in younger age groups (≥70: 1.52 [95% CI 1.48-1.56]; 40-49: 2.37 [95% CI 2.25-2.61]). CONCLUSIONS: Given the increasing burden that diabetes imposes, our findings will support policymakers in future planning for diabetes and enable targeting sub-groups with higher long-term costs for possible cost savings for the Tasmanian healthcare system.

Chronic Kidney Disease in Tasmania: Protocol for a Data Linkage Study.

BACKGROUND: Chronic kidney disease (CKD) is a significant and growing health burden globally. Tasmania has the highest state prevalence for non-Indigenous Australians and it has consistently had the lowest incidence and prevalence of dialysis in Australia. OBJECTIVE: To examine the gap between the high community prevalence of CKD in Tasmania and the low use of dialysis. METHODS: This is a retrospective cohort study using linked data from 5 health and 2 pathology data sets from the island state of Tasmania, Australia. The study population consists of any person (all ages including children) who had a blood measurement of creatinine with the included pathology providers between January 1, 2004, and December 31, 2017. This study population (N=460,737) includes within it a CKD cohort, which was detected via pathology or documentation of kidney replacement therapy (KRT; dialysis or kidney transplant). Kidney function (estimated glomerular filtration rate [eGFR]) was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula. Individuals with 2 measures of eGFR<60 mL/min/1.73 m2, at least 90 days apart, were identified as having CKD and were included in the CKD cohort. Individuals treated with dialysis or transplant were identified from the Australia and New Zealand Dialysis and Transplant Registry. RESULTS: The study population consisted of 460,737 people (n=245,573 [53.30%] female, mean age 47.4 years) who were Tasmanian residents aged 18 years and older and were followed for a median of 7.8 years. During the later 5 years of the study period, 86.79% (355,622/409,729) of Tasmanian adults were represented. The CKD cohort consisted of 56,438 people (ie, 12.25% of the study population; 53.87% (30,405/56,438) female, mean age 69.9 years) followed for a median of 10.4 years with 56,039 detected via eGFR and 399 people detected via documentation of KRT. Approximately half (227,433/460,737, 49.36%) of the study population and the majority of the CKD cohort (41,448/56,438, 73.44%) had an admission episode. Of the 55,366 deaths recorded in the study population, 45.10% (24,970/55,366) had CKD. CONCLUSIONS: Whole-of-population approaches to examine CKD in the community can be achieved by data linkage. Over this 14-year period, CKD affected 12.25% (56,438/460,737) of Tasmanian adult residents and was present in 45.10% (24,970/55,366) of deaths. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/20160.