Why is it important?:Sudden Infant Death Syndrome (SIDS) is the sudden and unexplained death of an apparently healthy infant, for which no cause can be found. A SIDS death usually occurs in healthy infants under 1 year of age, with the highest incidence between 1 and 4 months. A SIDS death occurs quickly, usually during sleep. There are several risk factors associated with SIDS: prone sleeping position, sleeping on a soft surface, maternal smoking during pregnancy, environmental tobacco smoke, overheating, late or no prenatal care, young maternal age, prematurity and/or low birthweight, and male sex. In Australia, the rate of SIDS declined by 84% between 1983 and 2003, with a sustained fall following the introduction in 1991 of the public health campaign encouraging parents to mitigate the known risk factors for SIDS deaths.
Findings:Between 1991 and 2008 there has been a significant decline in Indigenous death rates from SIDS in the three jurisdictions with adequate data quality for long-term trends (WA, SA and the NT). Over this period Indigenous SIDS deaths dropped from 62 deaths in 1991–93 to less than 5 deaths in 2006–08. While there have also been declines for other Australian infants there has been a significant reduction in the gap between Indigenous and other infants. Although the Indigenous rate remains 3 times higher, the absolute difference between Indigenous and other Australian infant rates has been almost eliminated. Recent trends (2001–08) in the five jurisdictions with adequate data quality for short-term trends (NSW, Qld, WA, SA and the NT) show a continuation of the decline in Indigenous SIDS rates (81%) and a significant closing of the gap.
However, analysis of infant mortality data in Western Australia has found a shift away in recent years from a classification of ‘SIDS’ towards a classification of ‘unascertainable’, particularly for Aboriginal infants. This has implications for the analysis of trends in SIDS over time (Freemantle et al. 2005). Note: the overall Indigenous infant mortality rate has also declined over this period (see measure 1.19).
During the five-year period 2004–08, there were 39 Indigenous deaths from SIDS in the five jurisdictions with adequate data quality (NSW, Qld, WA, SA and the NT). This represented 16% of all SIDS deaths—around 3 times the rate for non-Indigenous infants. SIDS deaths accounted for 7% of all Indigenous infant deaths. The number of deaths ranged from no deaths in South Australia to 22 in New South Wales.
Data on risk factors for SIDS show that Indigenous infants are more likely to be exposed. In 2008, nationally, 21% of Indigenous infants were slept prone. Aboriginal and Torres Strait Islander children were 3 times more likely to live in households with a regular smoker who smoked at home indoors (22% of children) compared with non-Indigenous children (7% of children) (see measure 2.03). In 2007, approximately half of Aboriginal and Torres Strait Islander mothers smoked during pregnancy—3 times that of non-Indigenous mothers (see measure 2.19). Access to antental care is high, but occurs later and less frequently (see measure 3.01). Low birthweight is more than twice as common among babies born to Aboriginal and Torres Strait Islander mothers than other Australian babies (see measure 1.01). In terms of protective factors, in 2004–05, 79% of Aboriginal and Torres Strait Islander infants aged 0–3 years in non-remote areas had been breastfed compared with 88% of non-Indigenous infants (see measure 2.24).
A small Queensland study of 30 Indigenous Australian women and 30 non-Indigenous Australian women (Panaretto et al. 2002) found that 37% of Indigenous infants were slept lying face down compared with 17% of non-Indigenous infants. The Indigenous households had significantly more members. Sixteen Indigenous women (53%) smoked during pregnancy compared with seven non-Indigenous women (23%) and 18 of the Indigenous women (60%) were smokers at the time of the interview. Smoking occurred inside 40% of Indigenous houses compared with 20% of non-Indigenous houses. This survey suggests SIDS risk factors may be higher in the Indigenous Australian population and new approaches to promoting SIDS awareness may be needed. A study in Western Australia found that 73% of Aboriginal and 60% of non-Aboriginal mothers whose infants died of SIDS, had smoked during their pregnancy (Freemantle, de Klerk et al. 2004). In a Perth study of Aboriginal mothers (Eades & Read 1999), 11% of their infants slept prone, 96% shared a room and 68% shared a bed. Sixty-five per cent of these mothers smoked during pregnancy and 80% of infants were regularly exposed to tobacco smoke. Eighty-nine per cent of the mothers initiated breastfeeding and 70% were breastfeeding at the time of the interview. The authors conclude that the prevalence of non-prone sleeping and breastfeeding are similar for Indigenous infants and other infants, but tobacco smoke exposure is significantly higher (see measure 2.03).
Disparities also exist between non-Indigenous populations and babies born to Indigenous mothers in Canada, New Zealand and the United States. For Inuit, excess mortality is observed for all major causes of infant death compared to the rest of Canada; the Maori SIDS rate was 1.4 per 1,000 live births, significantly higher than the non-Maori rate; and a 40% reduction in the infant mortality rate would be achieved if the gap in American Indian infant mortality for SIDS and low birthweight was closed (Smylie et al. 2010).
Implications:National statistics show promising trends in both the SIDS death rates for Indigenous infants and also in the gap. The higher rate ratio in SIDS mortality rates is similar to the rate ratio for a number of risk factors comparing Indigenous infants and other infants.
Sids and Kids Western Australia runs the Reducing the Risk of SIDS in Aboriginal Communities program to specifically target the high rates of SIDS among Indigenous infants. Aboriginal Coordinators educate and raise community awareness about preventative measures, such as safe sleeping practices. An evaluation of this program is underway. An outstanding question is whether anything more needs to be done specifically targeted to Aboriginal and Torres Strait Islander peoples or are the measures that have worked well for the general population sufficient? Additional Australian research on the prevalence of risk factors and their link to the higher rate of SIDS in Aboriginal and Torres Strait Islander babies would be very useful.
Figure 57 – SIDS mortality rates per 1,000 live births, Aboriginal and Torres Strait Islander and other Australian infants, WA, SA and NT, 1991–1993 to 2006–2008
Source: AIHW and ABS analysis of National Mortality Database
Text description of figure 57 (TXT 1KB)
Figure 58 – SIDS mortality rates per 1,000 live births, by age (months) and Indigenous status, NSW, Qld, WA, SA and NT, 2004–2008
Source AIHW and ABS analysis of National Mortality Database
Text description of figure 58 (TXT 1KB)
Table 31 – SIDS mortality rates per 1,000 live births and rate ratios, by Indigenous status, NSW, Qld, WA, SA and NT, 2004–2008
|New South Wales|
|Qld, WA, SA & NT|
Note: Data cells with small values have been randomly assigned to protect the confidentiality of individuals. As a result, some totals will not equal the sum of their components. Cells with a zero value have not been affected by confidentialisation.
Source: AIHW and ABS analysis of National Mortality Database