Causes2018-10-15T09:17:52+00:00

Bronchiectasis in Aboriginal and Torres Strait Islander people (see below for Mãori)

Bronchiectasis can develop in persons of any age and cultural background, however Aboriginal children in Central Australia have the highest rates of bronchiectasis in the world (Steinfort et al. 2008). The main causes include recurrent chest infections and reduced immune function.

In Aboriginal and Torres Strait Islander people, bronchiectasis is more likely to be caused by, or associated with, childhood infections. Studies have found that hospitalised pneumonia was an independent risk factor for bronchiectasis i.e. they were 15 times more likely than controls (Indigenous children hospitalised for other reasons) to develop bronchiectasis (OR 15, 95%CI 4-53) and the risk increased further in those experiencing recurrent episodes of hospitalised pneumonia.

These same risk factors for acute respiratory infections pertain to bronchiectasis. A combined (Australia, NZ and Alaska) study of Indigenous children with bronchiectasis found that the Indigenous children in all regions experienced substantial disparities in poverty indices and risk factors (ETS exposure, low education levels, etc.) common (similar rates) with their respective regional Indigenous populations. However, household crowding, prematurity and a high frequency and early onset of acute lower respiratory infections were associated with development of bronchiectasis.

Determinants of Health

It is important for healthcare providers to understand why the rates and disease patterns of bronchiectasis are more severe in Aboriginal and Torres Strait Islander communities, to ensure that improvements are targeted in research and treatment. In the context of Central Australia, there are a number of reasons why Aboriginal Australians are affected more severely.

Environment

It is common for extended families to live together as a way to preserve cultural traditions and maintain community strength.  Overcrowding in remote communities can be exacerbated by difficult access to housing and home maintenance services. With many people living in one house, it is easier for infections to spread amongst family, particularly in areas where extreme hot and cold weather patterns occur. In remote areas of Australia severe infections are more common. Recurrent exposure to severe infections can cause destruction of lung tissue, leading to bronchiectasis.

It is inappropriate to suggest that change in social living situations is the solution to preventing bronchiectasis. Healthcare professionals should liaise with community elders and service providers to optimise healthy living environments through strategies such as hand hygiene, good nutrition, clean water, sanitation and access to necessary services. By engaging with families, traditional healers and health centres, professionals can also encourage early presentation when sickness occurs to ensure effective treatment is provided.

Socioeconomic Disadvantage

It is important for professionals to recognise that many of the barriers between traditional culture and standard healthcare service provision involve high financial costs. When living in a remote community, a trip to hospital for one person may involve costs for petrol, food and accommodation for a whole family.  Medications and treatment modalities may require ongoing patient contribution, which may not be feasible when individuals carry financial responsibility for not only their immediate family, but also extended relations and community members.

Aboriginal and Torres Strait Islander people are represented across all employment sectors in Australia. However, an expectation to work is disrespectful to traditional life, and poorly informed assumptions made by non-Indigenous people can be incredibly detrimental. In establishing a healthcare environment where all Australians feel welcome, professionals must recognise and respect the lifestyle choices made by each and every person.

Community Responsibilities and Good Health

Good health is a focus of many traditions. However, there are different perspectives on how good health may be achieved. Some individuals may consider a healthy life to be one free of illness and injury, whilst others may recognise health through a strong connection to family, culture and country. In some cases health may not be the highest priority.

Even when health is a priority, many people will have complex obligations during periods of cultural business, or ongoing social responsibilities to family, children or elders in the community. Professionals should take the time to understand what constitutes good health for their patients, and how individuals can be supported to achieve their personal health goals. This may include standard investigations, medications and surgical procedures, however may also include returning home  – potentially during times of acute illness – to be closer to family and traditional healers.

It is important to provide patients with education regarding their current and long-term healthcare needs, recognising that these must be balanced with individual and community concerns.

Respiratory Infections

Data from the Australian Institute of Health and Welfare (AIHW 2011) demonstrates:

Respiratory disorders are the most common reason for General Practice encounters by Aboriginal and Torres Strait Islander Australians

Respiratory disease is the second most common self-reported chronic health condition, and the second most common cause of hospitalisation

The hospitalisation rates for respiratory disease in Aboriginal and Torres Strait Islander children aged 0-4 years are almost twice the rate for non-Indigenous children

A study of patients with bronchiectasis at Alice Springs Hospital enabled sputum culture review from 57 individuals (Steinfort et al. 2008), identifying a variety of infective agents including: Haemophilus influenza (81%), pseudomonas aeruginosa (26%), streptococcus pneumonia (19%), klebsiella pneumonia (9%), staphylococcus aureus (9%), klebsiella ozanae (6%), moraxella catarrhalis (6%), escherichia coli (4%), stenotrophomonas (2%), maltophilia (2%), morganella morganii (2%) and MAC (2%).

A report by the Northern Territory Government Centre for Disease Control (2016) notes that Australia has one of the lowest incident rates of TB in the world at 5-6 cases per 100,000. Whilst there is no clear increase in cases amongst Aboriginal and Torres Strait Islander people nationwide, the age-standardised incidence rate of Aboriginal Australians in the Northern Territory is 28.4 per 100,000.

Human T-Lymphotropic Virus Type-1

In Central Australian adults, Human T-Lymphotropic Virus Type-1 (HTLV-1) infection has been associated with bronchiectasis.

HTLV-1 is an organism that infects T-lymphocytes – a type of white blood cell in the body. It is an ancient virus common to Indigenous populations worldwide. HTLV-1 is transmitted through bodily fluids, and can occur during:

Unprotected sexual intercourse

Blood contact or transfusion

Pregnancy

Breastfeeding

HTLV-1 causes lifelong infection, and may result in leukaemia, lymphoma or myelopathy. It may also cause inflammation of the eyes, joints, muscles, skin, and lung tissue. There is evidence to suggest that HTLV-1 is strongly correlated with the development of chronic lung disease, including bronchiectasis.

HTLV-1 occurs at endemic rates in Central Australia. Reports of community epidemiology had previously indicated rates of 13.9% for the region. Recent studies of Central Australian inpatient cohorts have identified 59.8% of patients tested for HTLV-1 were seropositive (5), and 72% of bronchiectasis patients discharged from hospital were seropositive.

Disease progression in HTLV-1 carriers can be worsened by concurrent exposure to strongyloides stercoralis – a worm that lives in soil contaminated by human faeces. This parasite affects communities across Central Australia. If a person comes into contact with contaminated soil, the larvae can borrow through the skin and cause strongyloidiasis, an infection of the skin, gut, or lungs. In its severest form, strongyloidiasis can be life threatening.

Further research is required to investigate the pathophysiology and interactions between HTLV-1, strongyloides stercoralis and bronchiectasis.

The development of bronchiectasis is closely related to the environment and social welfare of the population. Health discrepancies based on ethnicity are less the result of genes but more due to historical, cultural and socioeconomic factors which affect lifestyle, behaviours and access to health care. Organisations should work closely with Aboriginal and Torres Strait Islander patients, families and community elders to optimise equal access to highest quality healthcare.

Bronchiectasis in Mãori people

Epidemiology

In 2003, the incidence of bronchiectasis in auckland children was 24/100,000 for Mãori compared to 4/100,000 for European groups (Edwards et al 2003).

The rate of hospitalisation for bronchiectasis in 2003-2005 were 3.6 times the rate for non-Mãori, with the rate rising to 6-fold at ages 45-64 (Crengle et al 2006).

In 2000, 27% of adults in South Auckland hospitalised with bronchiectasis were Mãori (Roberts et al 2012)

A recent study has shown hospital admission rates to be 5-fold higher for Mãori than non-Mãori (Bibby et al 2015).

Causes

Substandard housing, malnutrition, barriers to health care and inadequate education the the most likely contributors to the occurrence and outcomes of bronchiectasis (Crengle et al 2007).

In New Zealand, half of the cases of bronchiectasis in children and adults with a known cause were due to childhood infection (Edwards et al 2003, Roberts et al 2012).

Low immunisation rates in communities with social deprivation may also be a factor (Crengle et al 2007).

References