Mortality

Please select category from the dropdown list below.

Overview of the health of Indigenous people in Western Australia 2011    Introduction    Population structure    Births and pregnancy outcome    Mortality    Hospitalisation    Selected health conditions       Cardiovascular health       Cancer       Diabetes       Social and emotional wellbeing (including mental health)       Kidney health (renal disease)       Injury       Respiratory disease       Communicable diseases          Sexually transmitted infections          Hepatitis          HIV/AIDS          Other communicable diseases       Eye health       Ear health       Oral health    Health risk factors    Concluding comments

In 2009, 444 of the 12,566 deaths registered in WA were identified as being of an Indigenous person [1]. Based on the under-identification of Indigenous people in death registrations, the actual number of Indigenous deaths is likely to be between 480 and 620 (see above) [2][3].

The following summary measures of mortality are based on the numbers of registered deaths, so some caution should be exercised in their interpretation.

Expectation of life

In 2005-2007, after adjustment for the incompleteness of identification of Indigenous people in death registrations, the ABS estimates that Indigenous males born in WA could be expected to live to 65.0 years, 14 years less than the 79.0 years expected for non-Indigenous males [1] (Life expectancy at birth is the number of years a person born in the reference year can expect to live if they experience the current age-specific death rates. (Estimates were not available for WA and South Australia (SA) separately). In 2005-2007, the expectation of life at birth of 70.4 years for Indigenous females born in WA was almost 13 years less than the expectation of 82.9 years for non-Indigenous females born in WA. For the same time period, the estimates for Indigenous people nation-wide were 67.2 years for males and 72.9 years for females [1].

Age at death

In 2009, the median age at death for Indigenous males in WA was 50.6 years, which was 26.7 years less than for non-Indigenous males (77.3 years) 3 [1]. The median age at death for WA Indigenous females was 58.7 years, 24.9 years less than for WA non-Indigenous females (83.6 years).

In 2005-2009, death rates in WA were higher for Indigenous people than for non-Indigenous people across all age groups, with rate ratios highest in the middle adult years (Table 3) 4 [1]. (These ratios, being based on the numbers of deaths registered, are likely to underestimate the true differences between death rates for Indigenous people and the total population by 10-30%.) The greatest difference occurred among females and males aged 35-44 with rates nearly eight times those recorded for non-Indigenous males and females.

Table 3: Age-specific death rates and rate ratios for all causes, by sex, WA, 2005-2009

Age group	Males			Females
	Indigenous	Non-Indigenous	Rate ratio	Indigenous	Non-Indigenous	Rate ratio
Source: AIHW, 2010 [1]. Notes: Rates are per 100,000 population, except age 0. Rate ratio is the rate for Indigenous people divided by the rate for non-Indigenous people. Deaths for which Indigenous status was not stated were excluded from the calculation of rates.
0	11	3	3.5	8	3	2.4
1-4	113	23	4.9	60	12	4.9
5-14	33	9	3.8	19	8	2.5
15-24	247	66	3.7	126	26	4.8
25-34	446	90	5.0	248	40	6.3
35-44	898	122	7.4	530	68	7.8
45-54	1511	260	5.8	944	156	6.0
55-64	2786	602	4.6	2027	349	5.8
65 and over	7765	3913	2.0	6924	3455	2.0

Infant mortality

In 2007-2009, the infant mortality rate of 7.7 infant deaths per 1,000 live births for Indigenous people in WA was nearly three times the rate of 2.7 per 1,000 for non-Indigenous Western Australians [1]. (The infant mortality rate is the number of deaths of children under one year of age in a calendar year per 1,000 live births in the same calendar year.) The rate of 10.3 per 1,000 for Indigenous males was higher than the rate of 5.1 per 1,000 for Indigenous females.

Causes of death

In 2009, the most common causes of death for Indigenous people in WA were ischaemic heart disease and diabetes, which were responsible for 14.4% and 8.4% respectively of all Indigenous deaths5 (Table 4).

Table 4: Underlying cause of death, selected causes, Indigenous status, by sex, WA, 2009

Cause of death	Males (no.)	Females (no.)	Proportion of all Indigenous deaths (%)
Source: Derived from ABS 2011 [4].
Ischaemic heart disease	40	24	64
Diabetes	14	23	37
Land transport accidents	19	7	26
Intentional self-harm (suicide)	19	5	24
Malignant neoplasm (cancer) of trachea, bronchus and lung	14	5	19
Diseases of the urinary system	8	11	19
Cerebrovascular disease	10	7	17
Chronic lower respiratory disease	8	9	17
Other causes	107	114	221
All causes	239	205	444

The most recent valid data for comparing causes of death for Indigenous and non-Indigenous people reveal that the standardised mortality ratios (SMR) for cardiovascular disease (also known as ‘diseases of the circulatory system’ for males and females living in Queensland (Qld), WA, SA and the Northern Territory (NT) in 2001-2005 were 3.2 and 2.7 respectively (Table 5). For Indigenous males in 2001-2005, the next most frequent causes of death were injuries (including transport accidents, intentional self-harm and assault) (2.9 times the number expected from rates for the total male population of Qld, WA, SA and the NT), malignant neoplasms (cancers) (1.5); diseases of the respiratory system (4.3); and endocrine, nutritional and metabolic disorders (mainly diabetes) (7.5). For Indigenous females, the most frequent causes of death after cardiovascular disease was malignant neoplasms (1.6); injuries (3.5); endocrine, nutritional and metabolic disorders (10.1); and diseases of the respiratory system (3.6) [2].

Table 5: Numbers of Indigenous deaths, by cause and sex, and Indigenous standardised mortality ratios, Qld, WA, SA and the NT, 2001-2005

Cause of death	Males		Females
	Number	SMR	Number	SMR
Source: AIHW, 2008 [5]. Notes: The standardised mortality ratio (SMR) is the ratio of the number of Indigenous deaths occurring to the number expected if the age, sex and cause-specific rates of the total population applied to the Indigenous population. Due to under-identification of Indigenous deaths, these numbers and SMRs are likely to underestimate the true differences between the Indigenous and total populations by around 30%.
Circulatory	1150	3.2	856	2.7
External causes (inc. Injuries)	851	2.9	369	3.5
Neoplasms (inc. Cancer)	592	1.5	547	1.6
Respiratory	378	4.3	281	3.6
Endocrine, nutritional and metabolic	315	7.5	367	10.1
Digestive	251	5.8	182	5.1
Mental and behavioural disorders	101	5.8	72	3.1
Nervous system	122	2.9	69	1.6
Infectious/ parasitic	102	5.1	72	5.0
Genitourinary	79	4.8	119	6.0
Perinatal	126	2.9	82	2.3
Other	169	6	85	4.6

Endnotes

1. The median age at death is the age below which 50% of people die. The measure partly reflects the age structures of the respective populations, so it is a less precise measure than age-specific death rates.
2. Rate ratios are the Indigenous rate divided by the non-Indigenous rate for each age group.
3. Data available for 2009 do not enable a valid comparison of causes of death for Indigenous and non-Indigenous people, which would involve examination of standardised rates.

References

1. Australian Bureau of Statistics (2010) Deaths, Australia, 2009. Canberra: Australian Bureau of Statistics
2. Australian Bureau of Statistics, Australian Institute of Health and Welfare (2005) The health and welfare of Australia's Aboriginal and Torres Strait Islander peoples 2005. Canberra: Australian Institute of Health and Welfare and the Australian Bureau of Statistics
3. Australian Bureau of Statistics (2008) Indigenous mortality quality study, 2006-07 - information paper: census data enhancement. Canberra: Australian Bureau of Statistics
4. Australian Bureau of Statistics (2011) Causes of death, Australia, 2009. Canberra: Australian Bureau of Statistics
5. Australian Bureau of Statistics (2010) The health and welfare of Australia's Aboriginal and Torres Strait Islander peoples, 2010. Canberra: Australian Bureau of Statistics