Indigenous health risks

Nutrition

The nutritional status of Indigenous people is influenced by socio-economic disadvantage, and geographical, environmental and social factors [3]. Poor nutrition is a common risk factor for overweight and obesity, malnutrition, cardiovascular disease, type 2 diabetes, certain cancers, osteoporosis, and tooth decay [4][5]. The NHMRC has endorsed a number of dietary guidelines for infants, adolescents, adults, older Australians, women of childbearing age, and pregnant women [3]. The NHMRC guidelines recommend that adults consume a minimum of two serves of fruit and five serves of vegetables per day, selected from a wide variety of types and colours [6]. The guidelines also recommend including reduced-fat varieties of milk, yoghurts and cheeses, and choosing foods low in salt.

According to the 2004-2005 NATSIHS, 58% of Indigenous respondents aged 12 years or older living in non-remote areas consumed one serve or less of fruit per day, compared with 46% of non-Indigenous respondents [7]. That is, only 42% of Indigenous people aged 12 years or older living in non-remote areas and 54% of non-Indigenous respondents consumed fruit at the recommended level of two or more serves per day.

Almost two-thirds of Indigenous and non-Indigenous people aged 12 years or older living in non-remote areas reported consuming two to four serves of vegetables per day, but only 10% of Indigenous respondents and 14% of non-Indigenous respondents reported consuming five serves or more per day.

For respondents living in remote areas, the questions in the 2004-2005 NATSIHS were amended to whether they usually ate fruit and/or vegetables each day. The proportions of Indigenous people aged 12 years and older living in remote areas who did not consume these dietary items daily was substantially higher than for their counterparts living in non-remote areas - 15% and 2% respectively for vegetable consumption, and 20% and 12% respectively for fruit consumption [7][8].

More than three-quarters of Indigenous people aged 12 years or older living in non-remote areas reported that they usually drank whole milk (including full-cream powdered milk), with only 20% drinking reduced fat and/or skim milk [8]. In contrast, 45% of their non-Indigenous counterparts consumed reduced fat and/or skim milk and 45% whole milk. The consumption of reduced fat and/or skim milk was very low (6%) among Indigenous people aged 12 years or older living in remote areas, with 87% reporting that they drank whole milk.

More than four-fifths of Indigenous people aged 12 years or older living in remote areas reported 'sometimes' or 'usually' adding salt after cooking, compared with two-thirds of those living in non-remote areas [8].

The 2004-2005 NATSIHS also addressed the question of food security by asking respondents whether respondents ran out of food in the previous 12 months. Approximately 24% of Indigenous people aged 15 years and older reported they ran out of food in the 12 months before the survey, compared with 5% of non-Indigenous people [9]. Those in remote areas were more likely to report having run out of food than those in non-remote areas (36% compared with 20%). Approximately 8% of Indigenous people reported they went without food when they couldn't afford to buy more, compared with 2% of non-Indigenous people.

Physical activity

The National Physical Activity Guidelines for Adults recommend at least 30 minutes of moderate activity on most, preferably all, days of the week to enhance health and reduce the risk of cardiovascular disease and other chronic conditions [10]. Insufficient levels of physical activity have been shown to be a risk factor for cardiovascular disease, type 2 diabetes, certain cancers, depression, and overweight and obesity [11].

Data on the levels of physical activity of Indigenous people are limited [12]. After adjusting for differences in the age structures of the Indigenous and non-Indigenous populations, approximately 51% of Indigenous respondents in non-remote areas reported in the 2004-2005 NATSIHS their exercise level as sedentary (very low or no exercise), 27% as low and 21% as moderate or high, compared with 33%, 36% and 31% respectively of non-Indigenous people [9]. Sedentary or low levels of physical activity were highest among Indigenous people aged 45-54 years and 55 years or older (83% and 85% respectively); moderate or high levels of physical activity were highest among those aged 15-24 and 25-34 years (32% and 27% respectively). A higher proportion of Indigenous females than Indigenous males reported that their level of exercise was sedentary (51% compared with 42%).

Bodyweight

Body mass index (BMI - weight in kilograms divided by height in metres squared) is the standard measure for classifying a person's weight for height [13]. Being overweight (BMI between 25.0 to 29.9) or obese (BMI >= 30.0) increases a person's risk for cardiovascular disease, type 2 diabetes, respiratory diseases, renal disease, certain cancers, osteoarthritis, pregnancy complications, and psychosocial problems [12]. A high BMI can be a result of many factors, either alone or in combination, such as poor nutrition, physical inactivity, socioeconomic disadvantage, genetic predisposition, increased age, and alcohol and tobacco use [12][14]. Being underweight (BMI less than 18.5) can also have adverse health consequences, including decreased immunity (leading to increased susceptibility to some infectious diseases), osteoporosis (bone loss), decreased muscle strength, and hypothermia (lowered body temperature). The 2003 NHMRC dietary guidelines for adults recommend that adults prevent weight gain by being physically active and eating according to their energy needs.

Based on information collected as a part of the 2004-2005 NATSIHS, 57% of Indigenous people aged 15 years or older were overweight or obese, with no real difference according to remoteness of residence [8]. A slightly higher proportion of Indigenous men (58%) than Indigenous women (55%) was overweight or obese. Almost 6% of Indigenous people aged 15 years or older were underweight, with 4% of Indigenous men and 7% of Indigenous women having a BMI of less than 18.5. After adjusting for differences in the age structures of the two populations, the level of being overweight or obese was 1.2 times higher for Indigenous people aged 15 years or older than for their non-Indigenous counterparts.

In 2004-2005, Indigenous people over the age of 18 were more likely to be overweight or obese if: their self-reported health status was fair/poor (68%) compared with those whose health was excellent or very good (55%); they had three or more long-term health conditions (65% compared with 56% of those who had two or less long-term health conditions); they had circulatory problems (72% compared with 57% without circulatory problems); or had diabetes (83% compared with 57% of those without diabetes) [9]. The prevalence of overweight and obesity among Indigenous people aged 18 years and over has been steadily increasing in non-remote areas from 51% in 1995 to 56% in 2001 and 60% in 2004-2005.

Overweight and obesity were slightly more common among Torres Strait Islanders aged 15 years or older (61%) than among Aboriginal people in that age range (56%) (the difference is not statistically significant) [8]. The level of overweight and obesity was particularly high among Torres Strait Islanders living in the Torres Strait area, with 86% having a BMI of 25.0 or greater.

Immunisation

In response to the greater burden of communicable diseases among Indigenous people, the NHMRC has endorsed a series of special guidelines and schedules for immunisation of vaccine-preventable diseases, which include some extra vaccinations [15][16].

Respondents to the 2004-2005 NATSIHS reported that 88% of Indigenous children aged 0-6 years living in non-remote areas were fully immunised against the vaccine-preventable diseases included in the relevant NHMRC vaccination schedule [8]. The available immunisation records suggest the level fully immunised may be somewhat lower, as the proportions for the separate vaccines were: diphtheria and tetanus (79%), pertussis (whooping cough) (74%), hepatitis B (83%), Hib (73%), and MMR (measles, mumps, and rubella) (85%).

Three-fifths of Indigenous people aged 50 years or older reported to the 2004-2005 NATSIHS that they had been vaccinated against influenza in the previous 12 months, with vaccination levels higher for people living in remote areas (80%) than for those living in non-remote areas (52%) [8]. All of these levels were higher than that for non-Indigenous people (46%). Similarly, vaccination levels for pneumonia in the previous 5 years were higher for Indigenous adults aged 50 years or older (remote: 56%; non-remote: 26%; all: 34%) than that for their non-Indigenous counterparts (20%).

Breastfeeding

Breast milk, which is the natural and optimum food for babies, contains proteins, fats and carbohydrates at levels that are appropriate for an infant's metabolic capacities and growth requirements [3]. It also has anti-infective properties and contains immunoglobulins which provide some immunity against early childhood diseases [17]. The NHMRC recommends that as many infants as possible be exclusively breastfed until six months of age and that mothers then continue breastfeeding until 12 months of age [16].

According to the 2004-2005 NATSIHS, 79% of Indigenous children aged less than four years living in non-remote areas were reported to have been breastfed for at least some period [8]. This level is slightly lower than the 88% of non-Indigenous children aged less than four years who had been breastfed. A similar proportion of Indigenous and non-Indigenous infants had been breastfed for six to 12 months (19% and 22% respectively) and for 12 months or more (13% and 14% respectively). On the other hand, the findings of the WAACHS suggest that mothers of Indigenous children were more likely to initiate breastfeeding and breastfeed for longer than mothers in the general population, particularly those living in more isolated areas [18].

The Footprints in time - the longitudinal study of Aboriginal children collected data from 11 sites (rural, remote and urban) around Australia in 2008-2009 [19]. Data on breastfeeding from this study showed that 22% of Indigenous infants had been breastfed for at least 12 months and that there was a positive correlation between the length of breastfeeding and the relative isolation of the family.

Tobacco smoking

Smoking tobacco increases the risk of cardiovascular disease, some cancers, lung diseases, and a variety of other health conditions [20]. Smoking is also a risk factor for complications during pregnancy and is associated with preterm birth, small for gestational age babies, low birthweight, and perinatal death [21]. Passive smoking is also of concern to health, with children particularly susceptible to problems including middle ear infections, asthma, respiratory infections, reduced lung function, low birthweight, and sudden infant death syndrome [20].

In 2003, tobacco smoking was the leading cause of the burden of disease and injury among Indigenous people, responsible for 12.1% of the total burden and one-fifth of all deaths [22].

One-half of Indigenous people (50%) aged 18 years or older reported to the 2004-2005 NATSISS that they smoked daily. Overall, the proportion of Indigenous men who smoked (51%) was slightly higher than the proportion of Indigenous women who smoked (49%) [8]. The level of smoking is slightly higher for Indigenous people living in remote areas (52%) than for those living in non-remote areas (49%). The level of smoking among Indigenous people has not really changed since at least 1994 (52%) [23].

The proportions of people smoking daily were similar for Torres Strait Islanders (49%) and Aboriginal people (50%) overall, but the proportion of daily smokers among Torres Strait Islanders living in the Torres Strait area was lower (38%)[8].

After adjusting for differences in the age structures of the two populations, daily smoking was 2.2 times more common among Indigenous people aged 15 years or older in 2004-2005 than among their non-Indigenous counterparts [8]. Even higher rates of smoking have been reported among Indigenous mothers. In 2007, in the jurisdictions that provided data (NSW, Qld, WA, SA, Tas, the ACT and the NT), smoking during pregnancy was more than three times more common among Aboriginal and Torres Strait Islander mothers than among non-Indigenous mothers (52% compared with 15%)[24].

Alcohol use

Regular drinking at harmful levels leads to a significant increase in risk of chronic ill-health and premature death, and binge drinking places both the drinker and others at increased risk of injury and morbidity [25]. Alcohol consumption in pregnancy can result in a spectrum of harms for the unborn child; the risk of birth defects is greatest when there is high and frequent alcohol intake in the first trimester, but any alcohol exposure throughout pregnancy can impact on the development of the foetal brain [26].

In 2003, alcohol was the fifth leading cause of the burden of disease and injury among Indigenous people, responsible for 6.2% of the total burden of disease and 7% of all deaths [22]. Just over one-fifth of burden due to injury and more than one-sixth of burden due to mental disorders were attributable to alcohol.

Surveys have shown consistently that Indigenous people are less likely to drink alcohol than non-Indigenous people, but those that do drink are more likely to consume it at hazardous levels [25][27].

The 2007 NDSHS found that 23% of Indigenous people aged 14 years or older were abstainers or ex-drinkers compared with 17% of non-Indigenous people aged 14 years or older [27].

Analyses involving the 2004-2005 NATSIHS found that the proportions of people aged 18 years or older who had never consumed alcohol or had not done so for more than 12 months was 24% for Indigenous people and 15% for non-Indigenous people [8]. Seventeen per cent of Indigenous men and 11% of non-Indigenous men aged 18 years or older had never consumed alcohol or had not done so in the previous 12 months; the proportions for Indigenous and non-Indigenous females were 30% and 20% respectively.

On the other hand, analysis derived from the 2004-2005 NATSIHS, found that the proportions of people aged 18 years or older who consumed alcohol at a 'high risk' level were 8% for Indigenous people and 6% for non-Indigenous people ('high risk' is defined as daily consumption of six standard drinks or more for males and four standard drinks or more for females) [8]. High risk alcohol consumption was reported for 11% of Indigenous males and 8% of non-Indigenous males, and for 6% of Indigenous females and 3% of non-Indigenous females.

Information about levels of total abstinence or abstinence for greater than 12 months and high risk consumption are not available by remoteness of residence, but consumption at 'risky' and 'high risk' levels (four and six standard drinks or more for males, and two and four standard drinks or more for females respectively) were slightly higher for Indigenous people aged 18 years or older living in remote areas (17%) than for their counterparts living in non-remote areas (15%) (the difference is not statistically significant) [8]. Compared with results from the 2001 NHS, consumption at 'risky' and 'high risk' levels increased by five percentage points for Indigenous people living in remote areas and decreased by two percentage points for those living in non-remote areas.

Alcohol consumption at 'risky' or 'high risk' levels was more common among Aboriginal people aged 18 years or older (17%) than among Torres Strait Islanders in that age range (13%) (the difference is not statistically significant) [8]. The level of 'risky' or 'high risk' alcohol consumption was even lower among Torres Strait Islanders living in the Torres Strait area (9%).

In 2009, the NHMRC introduced revised guidelines that depart from specifying 'risky' and 'high risk' levels of drinking. The guidelines seek to estimate the overall risk of alcohol-related harm over a lifetime and to reduce the level of risk to one death for every 100 people [26]. For men and women, guideline one states that to reduce the risk of alcohol-related harm over a lifetime, no more than two standard drinks should be consumed on any day, and guideline two states that to reduce the risk of injury on a single occasion of drinking, no more than four standard drinks should be consumed. Guideline three recommends avoiding alcohol for those under 15 years, and delaying alcohol for those aged 15 to 17 years. Guideline four recommends pregnant and breast feeding women avoid alcohol.

References

1. Marmot M, Wilkinson R, eds. (1999) Social determinants of health. Oxford: Oxford University Press
2. Carson B, Dunbar T, Chenhall RD, Bailie R, eds. (2007) Social determinants of Indigenous health. Crows Nest, NSW: Allen and Unwin
3. National Health and Medical Research Council (2000) Nutrition in Aboriginal and Torres Strait Islander peoples: an information paper. Canberra: National Health and Medical Research Council
4. National Public Health Partnership (2001) National Aboriginal and Torres Strait Islander Nutrition Strategy and Action Plan 2000-2010 and first phase activities 2000-2003. Canberra: National Public Health Partnership
5. Australian Institute of Health and Welfare (2002) Australia's health 2002: the eighth biennial report of the Australian Institute of Health and Welfare. Canberra: Australian Institute of Health and Welfare
6. National Health and Medical Research Council (2003) Dietary guidelines for Australian adults. Canberra: NHMRC
7. Australian Health Ministers’ Advisory Council (2008) Aboriginal and Torres Strait Islander health performance framework report 2008. Canberra: Department of Health and Ageing
8. Australian Bureau of Statistics (2006) National Aboriginal and Torres Strait Islander Health Survey: Australia, 2004-05. Canberra: Australian Bureau of Statistics
9. Australian Institute of Health and Welfare (2008) Aboriginal and Torres Strait Islander health performance framework, 2008 report: detailed analyses. Canberra: Australian Institute of Health and Welfare
10. National physical activity guidelines for