What role do hospitals play in treating asthma?

People with asthma require admission to hospital when flare-ups or 'attacks' are potentially life-threatening or when they cannot be managed at home or by a GP.

Data from the AIHW National Hospital Morbidity Database (NHMD) show that in 2014–15, there were 39,500 hospitalisations where asthma was the principal diagnosis. The rate of hospitalisations for asthma was 171 per 100,000 population. The rate among children aged 0–14 (451 per 100,000 population) was markedly higher than the rate among people aged 15 and over (98 per 100,000 population).

Over the 10 years to 2014–15, the age-standardised rate of hospitalisations for asthma for children aged 0–14 decreased overall, falling from 539 to 450 per 100,000 population. Over the same period, the age-standardised rate of hospitalisations for asthma for those aged 15 and over flucuated between 88 and 102 per 100,000 population.

Hospitalisation rates differ by sex and age (Figure 1). In 2014–15, boys aged 0–14 were 1.7 times as likely as girls of the same age to be admitted to hospital for asthma; conversely, of those aged 15 and over, females were 2.3 times as likely as males to be admitted to hospital for asthma. These differences in hospitalisation by sex and age reflect in part the difference in the prevalence of asthma—which is more common in males than females for those under 15, and more common in females than in males for those over 15. See Prevalence by age and sex.

Figure 1: Hospitalisation rates for asthma, by sex and broad age group, 2005–06 to 2014–15

The horizontal line chart shows that hospitalisation rates for asthma remained relatively steady for both males and females aged 15 and over between 2005–06 and 2014–15. Among children aged 14 and under, rates declined slightly for both males and females.

Notes

  1. Age-standardised to the 2001 Australian Standard Population.
  2. Asthma classified according to International Classification of Diseases, 10th Revision, Australian Modification (ICD-10-AM) (8th edition for 2013–14 to 2014–15, earlier editions for 2004–05 to 2012–13) codes J45 and J46.
  3. Hospitalisations for which the care type was reported as Newborn with no qualified days, and records for Hospital boarders and Posthumous organ procurement have been excluded.
  4. Trend data should be interpreted with caution; see the NHMD data quality statement for more information.

Source: AIHW National Hospital Morbidity Database (Data table).

Seasonal variation in hospitalisations for asthma

Among children, the peaks for asthma hospitalisations occur in late summer (February) and autumn (May) (Figure 2 and Figure 3). The peak in February is likely related to respiratory infections associated with returns to school and childcare after the summer break. This has been found during similar peaks in September in Northern Hemisphere countries; lower use of preventer medication during holidays may also contribute.

Among adults, hospitalisations for asthma are highest in winter and early spring (June through to September), particularly in people aged 65 years and older. This coincides with the annual winter 'flu' season and may reflect the rise in respiratory infections observed then.

Figure 2: Weekly variation in hospitalisation rates for asthma, by age-group (all ages comparison), 2014

The horizontal line chart shows that the weekly hospitalisation rate for asthma in children aged 14 and under varies considerably throughout the year and is consistently higher than the rates for adults aged 15 and over.

Notes

  1. Data obtained from records of separations, reported by period of hospital admission.
  2. Hospitalisations for which the care type was reported as Newborn with no qualified days, and records for Hospital boarders and Posthumous organ procurement have been excluded.
  3. Asthma classified according to International Statistical Classification of Diseases and related Health problems, 10th Revision, Australian Modification (ICD-10-AM) (7th and 8th edition) codes J45 and J46.
  4. Admissions per week for 2014. Only full weeks are shown.

Source: AIHW National Hospital Morbidity Database (Data table).

Figure 3: Weekly variation in hospitalisations for asthma, children (2–14) and adults (15 and over) 2014

The two horizontal line charts shows that the peak seasons for asthma hospitalisations in children aged 14 and under are late summer and autumn. For those aged 15 and over hospitalisations peak in late winter and early spring and this peak is highest for those aged over 65.

Notes

  1. Data obtained from records of separations, reported by period of admission.
  2. Hospitalisations for which the care type was reported as Newborn with no qualified days, and records for Hospital boarders and Posthumous organ procurement have been excluded.
  3. Asthma classified according to International Statistical Classification of Diseases, 10th Revision, Australian Modification (ICD-10-AM) (7th and 8th edition) codes J45 and J46.
  4. Average admissions per week for 2014. Only full weeks are shown.

Source: AIHW National Hospital Morbidity Database (Data table).

Hospitalisations for asthma and all causes by age group

While most hospitalisations (all causes) in 2014–15 were for older people, the majority of hospitalisations for asthma were for children. In 2014–15, more than half (52%) of the 39,502 hospitalisations for asthma in Australia were for children aged 0–14, while this group comprised 6% of all hospitalisations (for all causes).

Figure 4: Hospitalisations for asthma and all causes, by age group, 2014–15

The vertical bar chart shows that in 2014–15, the most asthma hospitalisations were for children aged 0-4 (30%25). By comparison, the majority of hospitalisations for all causes were in adults aged 35–64 and 65 and over (38%25 and 41%25, respectively).

Notes

  1. Hospitalisations for which the care type was reported as Newborn with no qualified days, and records for Hospital boarders and Posthumous organ procurement have been excluded.
  2. Asthma classified according to the International Statistical Classification of Diseases, 10th Revision, Australian Modification (ICD-10-AM) (8th edition) codes J45 and J46.

Source: AIHW National Hospital Morbidity Database (Data table).

References

  1. AIHW National Hospital Morbidity Database (NHMD) 2014–15 data quality statement.
  2. National Casemix and Classification Centre (NCCC) 2012. The international statistical classification of diseases and related health problems, 10th revision, Australian modification (ICD-10-AM), Australian Classification of Health Interventions (ACHI) and Australian Coding Standards (ACS), 8th edn. Wollongong: University of Wollongong.