Prevalence, incidence and risk factors of diabetes in Australian adults aged ≥45 years: A cohort study using linked routinely-collected data

Hongmei Zhang; Kris Rogers; Louisa Sukkar; Min Jun; Amy Kang; Tamara Young; Anna Campain; Alan Cass; Clara K Chow; Elizabeth Comino; Celine Foote; Martin Gallagher; John Knight; Bette Liu; Thomas Lung; Martin McNamara; David Peiris; Carol Pollock; David Sullivan; Germaine Wong; Sophia Zoungas; Meg Jardine; Carinna Hockham; EXTEND45 Steering Committee

doi:10.1016/j.jcte.2020.100240

Prevalence, incidence and risk factors of diabetes in Australian adults aged ≥45 years: A cohort study using linked routinely-collected data

J Clin Transl Endocrinol. 2020 Nov 10:22:100240. doi: 10.1016/j.jcte.2020.100240. eCollection 2020 Dec.

Authors

Hongmei Zhang^{1

2}, Kris Rogers^{1

3}, Louisa Sukkar^{1

4}, Min Jun^{1

5}, Amy Kang^{1

5}, Tamara Young^{1

5}, Anna Campain^{1

5}, Alan Cass⁶, Clara K Chow^{1

7

8}, Elizabeth Comino⁹, Celine Foote^{1

10}, Martin Gallagher^{1

5

10

11}, John Knight^{1

5}, Bette Liu¹², Thomas Lung^{1

5}, Martin McNamara¹³, David Peiris^{1

5}, Carol Pollock^{14

15}, David Sullivan^{11

16}, Germaine Wong^{4

17}, Sophia Zoungas^{1

18}, Meg Jardine^{1

5

10}, Carinna Hockham^{1

5}; EXTEND45 Steering Committee

Affiliations

¹ The George Institute for Global Health, UNSW, Sydney, NSW, Australia.
² Department of Endocrinology, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
³ Graduate School of Health, University of Technology Sydney, Sydney, NSW, Australia.
⁴ School of Public Health, University of Sydney, Sydney, Australia.
⁵ Faculty of Medicine, University of New South Wales, Sydney, Australia.
⁶ Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia.
⁷ Westmead Applied Research Centre, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
⁸ Department of Cardiology, Westmead Hospital, Sydney, Australia.
⁹ Centre for Primary Health Care and Equity, University of New South Wales, Sydney, NSW, Australia.
¹⁰ Concord Repatriation General Hospital, Sydney, NSW, Australia.
¹¹ Sydney Medical School, University of Sydney, Sydney, Australia.
¹² School of Public Health and Community Medicine, University of New South Wales, Sydney, NSW, Australia.
¹³ The Sax Institute, Sydney, NSW, Australia.
¹⁴ Renal Division, Kolling Institute for Medical Research, Sydney, Australia.
¹⁵ University of Sydney, Sydney, Australia.
¹⁶ Department of Chemical Pathology, Royal Prince Alfred Hospital, Sydney, Australia.
¹⁷ Centre for Transplant and Renal Research, Westmead Hospital, Sydney, Australia.
¹⁸ School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia.

Abstract

Aims: To use linked routinely-collected health data to estimate diabetes prevalence and incidence in an Australian cohort of adults aged ≥45 years, and examine risk factors associated with incident disease.

Research design and methods: The EXamining ouTcomEs in chroNic Disease in the 45 and Up Study (EXTEND45) Study is a linked data study that combines baseline questionnaire responses from the population-based 45 and Up Study (2006-2009, n = 267,153) with multiple routinely-collected health databases up to December 2014. Among participants with ≥1 linked result for any laboratory test, diabetes status was determined from multiple data sources according to standard biochemical criteria, use of glucose-lowering medication or self-report, and the prevalence and incidence rate calculated. Independent risk factors of incident diabetes were examined using multivariable Cox regression.

Results: Among 152,169 45 and Up Study participants with ≥1 linked laboratory result in the EXTEND45 database (mean age 63.0 years; 54.9% female), diabetes prevalence was 10.8% (95% confidence interval [CI] 10.6%-10.9%). Incident disease in those without diabetes at baseline (n = 135,810; mean age 62.5 years; 56.1% female) was 10.0 per 1,000 person-years (95% CI 9.8-10.2). In all age groups, diabetes incidence was lower in women compared to men, an association that persisted in the fully adjusted analyses. Other independent risk factors of diabetes were older age, being born outside of Australia (with the highest rate of 19.2 per 1,000 person-years observed in people born in South and Central Asia), lower education status, lower annual household income, residence in a major city, family history of diabetes, personal history of cardiovascular disease or hypertension, higher body mass index, smoking and long sleeping hours.

Conclusions: Our study represents an efficient approach to assessing diabetes frequency and its risk factors in the community. The infrastructure provided by the EXTEND45 Study will be useful for diabetes surveillance and examining other important clinical and epidemiological questions.

Keywords: Administrative data; Big data; Diabetes MELLITUS; Incidence; Prevalence; Risk factors.