The Burden and Contributors to Cardiovascular Disease and

Diabetes in Indigenous Australians

Alex Brown

Baker IDI

Years of Life Lost (YLL) for the leading disease and injury categories – Indigenous persons 2003

CVD & Diabetes

The Health and Welfare of Australia’s Aboriginal and Torres Strait and Islander Peoples 2008 ABS Catalogue No. 4704.0 AIHW Catalogue No. IHW 21

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Contributors to the Gap

16.7 years 1996-2000 19.0 years 1996-2000

B/w 1996-2000

NCD - 77% Gap in LE

Grp I - 15-16%

CVD – 33%

GUT – 9%

DM – 9%

Chronic Resp - 9%

Injury – 8%

Zhao and Dempsey, MJA 2006

Driving Life Expectancy Differentials

Source: AIHW Chronic Disease and Associated Risk Factors in Australia, 2006.

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Risk factor prevalence in Australian populations - glucose intolerance

Daniel M, Rowley KG, McDermott R, O’Dea K. Diabetes and impaired glucose tolerance in Aboriginal Australians: prevalence and risk. Diab Res Clin Pract 2002; 57: 23-33.

Dunstan D et al. Diabesity and associated disorders in Australia 2000. International Diabetes Institute, Melbourne, 2000

DIABETES MORTALITY -AUSTRALIA

Male Death Rates - Diabetes Female Death Rates - Diabetes

The Health and Welfare of Australia’s Aboriginal and Torres Strait and Islander Peoples 2008 ABS Catalogue No. 4704.0 . AIHW Catalogue No. IHW 21

Cardiovascular Consequences of DM• Clustered risk factors –MetS, dyslipidaemia, behavioural• CHD - Diffuse /Multi-vessel Disease • Silent Ischaemia• Late diagnosis/recognition• Complications of MI more frequent in DM

– CHF• Diabetic Cardiomyopathy• PVD• CVA• Absolute risk equivalent to PMHx of CHD

Impact of DM on CHD Incidence – INTERHEART I

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DM, CKD and CHD in Indigenous Australians

Wang and Hoy, Kidney Int 2005Wang and Hoy. MJA 2005

CAD and Diabetes in Aboriginal People

Risk of Incident CVD in Aboriginal People – Central Australia (n=739)

Rowley, Brown et al

DM AND CVD IN CENTRAL AUSTRALIA

Baseline Demographics and Clinical Characteristics, CASPA Cohort 2001-2002.

IndigenousN=214

Non-IndigenousN=278

p-Value

Mean age (± SD) years 50.1 (12.5) 59.3 (12.5) <0.001

Male (%) 57.0% 69.8% 0.003

History of CHD 39.3% 45.5% 0.166

Prior CABG 3.3% 9.4% 0.008

Hypertension 62.1% 45.0% <0.001

Smoker (current) 42.5% 35.3% 0.001

Dyslipidaemia 34.1% 38.5% 0.318

Diabetes Mellitus 55.6% 30.2% <0.001

CKD (GFR <60) 39.3% 24.7% 0.001

End stage renal failure 16.4% 1.8% <0.001

ACS Risk Stratification NSTEACS - High Risk STEMI

65.9%22.9%

49.3%20.5%

<0.0010.402

ACS onset in rural location 112 (47.7%) 23 (8.0%) < 0.001

Late Presentation >12hrs 63 (28.5%) 46 (17.1) 0.002

ACS Co-Morbidity by Ethnicity

64

29

74

68

Indigenous (n=235)

DMDM and CKD

CKD

24

51

63

149

DM DM and CKD

CKD

Non-Indigenous (n=287)

ACS and DM 59%

ACS + DM + CKD 27%

ACS + CKD 12%

ACS alone 29%

ACS + DM 30%

ACS + DM + CKD 8%

ACS + CKD 18%

ACS alone 52%

p=0.0001

Age Adjusted Survival and MACE-Free Survival – ACS [Males]

Indigenous

Non-Indigenous

HR = 3.762 [2.15 - 6.58]; p < 0.001 HR = 2.061 [1.40 - 3.02]; p < 0.001

CVD RISK PREDICTION AND DM

WANG, ROWLEY, BROWN ET AL 2009

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Potential Pathophysiological Pathways linking Chronic Stress, Depression and Atherogenesis. Adapted from Rozanski et al

Chronic Stress

Negative Emotional

States

CN

S M

ediated Effects

HPA Activation

SNS Activation

Adverse Behaviours

ANS Dysfunction

Insulin Resistance

Obesity

Inflammation

Platelet Activation

HPA Dysfunction

Endothelial Dysfunction

Depression in Aboriginal men -MHM

INDEPENDANT CORRELATES OF OBESITY IN ABORIGINAL MEN

Diabetes and Heart Disease -The Rumsfeld Criteria

“There are known knowns; there are things we know we know.

We also know there are known unknowns; that is to say there are some things we know we do not know.

But there are also unknown unknowns- the ones we don’t know we don’t know”

Fmr US Sec Defence, Donald Rumsfeld

The Known Known's – CVD AND DM

• Extremely common• DM is bad for your heart• Independent contributor to CVD in men and women • Independent predictor of adverse CVD outcomes• Commonly co-morbid in Indigenous populations• Accelerated atherogenesis the primary driver of excess death

and morbidity in DM• Same treatments are effective in DM• We know what we have to do• We know the system isn’t doing its job

Known Unknowns

• How to best deliver what needs to be done– Community based interventions– System level reforms– Reducing the evidence-practice gaps– Access

• Incorporating culture as a protective, preventative, management and palliative process

• SDIH • Racism/Stress/Marginalisation – biopsychosocial pathways to DM/CVD• Burden of CHF/interplay of DM among Indigenous peoples• How best to engage the family as the unit of intervention• Disadvantage across the life-course