4373.0 - National Health Survey: Asthma and Other Respiratory Conditions, Australia, 1995  
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 11/11/1998   
   Page tools: Print Print Page Print all pages in this productPrint All

INTRODUCTION

This publication provides information on persons with respiratory conditions. The statistics are compiled from information collected in the 1995 National Health Survey (NHS). Topics covered in the publication include those indicated below and also respiratory conditions considered by place of birth, States and Territories, general health and wellbeing (SF-36) and health-related actions.

PREVALENCE OF RESPIRATORY CONDITIONS

The prevalence of asthma and other respiratory conditions is a concern for both health authorities and the general population in terms of personal, social and economic costs.

In 1995, 37% of Australians (6.7 million people) had a respiratory condition. The most commonly occurring respiratory condition was hayfever, which affected 14% of the population, followed by asthma (11%) and sinusitis (10%).

Hayfever, asthma, sinusitis, and bronchitis and/or emphysema were most likely to be a long-term condition, although they may have been experienced recently. In part, this reflects the chronic nature of these conditions. That is, once contracted, they would be continually present (e.g. emphysema), or experienced as recurring episodes (e.g. hayfever).

Conversely, common cold, influenza, and cough and/or sore throat were mainly experienced as a recent illness only. This reflects the acute nature of these conditions which may be expected to occur as discrete, non-recurring episodes.

There was an increase in the prevalence of respiratory conditions from 35% in 1989-90 to 37% in 1995. The largest increase was for sinusitis, which rose from 4% to 10%. The common cold was the only condition which decreased.


PERSONS WITH RESPIRATORY CONDITIONS
1989-90(a)
1995
    Type of condition
'000
%
'000
%
    Hayfever
1 752.9
10.3
2 515.4
13.9
    Asthma
1 444.1
8.5
2 041.4
11.3
    Sinusitis
727.2
4.3
1859.0
10.3
    Common cold
1 633.1
9.6
1 028.3
5.7
    Bronchitis and/or emphysema
586.8
3.5
777.8
4.3
    Influenza
514.6
3.0
573.0
3.2
    Cough and/or sore throat
421.3
2.5
540.8
3.0
    Other respiratory conditions(b)
415.8
2.4
475.8
2.6
    All respiratory conditions(c)
5 895.6
34.7
6 748.7
37.4
    All respiratory conditions standardised(d)
5 867.1
34.5
6 748.7
37.4
    Total persons
16 988.8
100.0
18 061.1
100.0

(a) 1989-90 National Health Survey.
(b) See Explanatory Notes, paragraph 14 in the publication.
(c) Each person may have reported more than one type of condition and therefore components may not add to totals.
(d) Data have been age and sex standardised (see Explanatory Notes, paragraphs 19 and 20 in the publication).

The increase in the rate of respiratory conditions between 1989-90 and 1995 may be the result of a number of factors including: actual increased prevalence of respiratory conditions, heightened awareness of these conditions and/or improved identification and treatment of these conditions. The increase cannot be attributed to the ageing of the population. With the exception of bronchitis and/or emphysema, the rate of the most common respiratory conditions generally decreased with age. This is confirmed by the overall age and sex standardised rate which showed a slightly greater increase in the prevalence of respiratory conditions than the observed rate.


Age and sex

In 1995, the prevalence of respiratory conditions in the population peaked in early adulthood and then generally declined with age, except for an increase in males in later years. Rates were considerably higher for females than for males, for each age group from 15 to 64 years. Consequently the overall rate for respiratory conditions was higher for females (39%) than for males (36%).



Seasonal patterns

To investigate seasonal patterns, information on people who experienced a respiratory condition as a recent illness, including recent episodes of long-term conditions, was considered according to the season in which the interview was conducted.

In 1995, 22% of the total Australian population had a recent respiratory illness. Recent respiratory illnesses were most prevalent in winter (25%) and spring (24%). They were less prevalent in summer (17%) and autumn (19%).

There was little seasonal variability in asthma experienced as a recent illness. The common cold showed much greater seasonal variation and was experienced by a higher proportion of people in spring and winter than in summer and autumn, as was influenza. Summer, then spring, were the seasons when hayfever was at its peak.



SMOKING

Smoking has been identified as a health risk factor for many conditions, including respiratory conditions. In 1995, 24% of Australian adults (aged 18 years or more) were current smokers, a further 27% were ex-smokers and 49% had never smoked.

When age and sex standardised rates for adults are compared, the prevalence of respiratory conditions overall was higher in smokers (37%) and in ex-smokers (41%) than in those who had never smoked (36%). These differences were particularly apparent in the case of bronchitis and/or emphysema, where the standardised rate for smokers (9%) was nearly twice that of ex-smokers (5%) and three times that of those who had never smoked (3%). Rates for asthma were also higher among smokers (11%) and ex-smokers (11%) than among those who had never smoked (9%).

In contrast, for hayfever the standardised rate was lower for smokers (12%) than for ex-smokers (18%) and for those who had never smoked (17%).

ADULTS, Smoker Status and Respiratory Conditions-Standardised rates(a)
SMOKER STATUS
Smoker
Ex-smoker
Never smoked
Total persons
    Type of condition
%
%
%
%
    Hayfever
12.3
17.9
17.0
16.0
    Asthma
11.0
10.7
8.5
9.6
    Sinusitis
11.9
13.4
12.0
12.3
    Common cold
3.9
4.6
4.6
4.4
    Bronchitis and/or emphysema
9.2
5.0
3.0
4.8
    Influenza
3.6
3.7
2.8
3.3
    Cough and/or sore throat
2.0
2.7
2.5
2.4
    Other respiratory conditions(b)
1.9
2.9
1.9
2.2
    All respiratory conditions(c)
37.3
40.6
36.4
37.4
    Total persons
100.0
100.0
100.0
100.0

(a) Data have been age and sex standardised (see Explanatory Notes, paragraphs 19 and 20 in the publication).
(b) See Explanatory Notes, paragraph 14 in the publication.
(c) Each person may have reported more than one type of condition and therefore components may not add to totals.

The prevalence of asthma in young children living in households with one or more smokers was higher than in non-smoking households. Of those aged 0-4 years, 13% in households with one or more smokers had asthma compared with 9% in households where there were no smokers. Of those aged 5-9 years, the rate of asthma was 22% in smoking households and 18% in non-smoking households. In contrast, for children aged 10-14, asthma was less prevalent in those living in smoking households (17%) than those in non-smoking households (20%). Differences in asthma between smoking and non-smoking households were proportionally greater for boys than for girls in each age group under 15 years. The differences between non-smoking households and those with one or more adults who were ex-smokers were not investigated as no information was collected on how recently people had given up smoking.

DEATHS DUE TO RESPIRATORY CONDITIONS

This section uses statistics collected from State and Territory Registrars of Births, Deaths and Marriages. Detailed mortality statistics are published annually in Causes of Death, Australia (Cat. no. 3303.0).

In 1996 there were 10,298 deaths for which a respiratory condition was identified as the underlying cause, accounting for 8% of all deaths in that year.

To allow comparison over time, annual death rates have been age standardised to the total Australian population as at 30 June 1991. Between 1981 and 1996, standardised death rates for respiratory conditions showed considerable fluctuation. The male rate was consistently higher than the female rate. However, since 1981, the difference between the male and female rates has narrowed. This is due mostly to a decline in the male rate, which decreased from approximately three times the female rate in 1981 (96.4 per 100,000 population compared with 32.5) to about twice the female rate in 1996 (71.1 compared with 38.1).

The trend in deaths due to respiratory conditions as a whole reflects the pattern for bronchitis and/or emphysema which accounted for 67% of male and 53% of female deaths from respiratory conditions in 1996. Between 1981 and 1996 the male standardised death rate for bronchitis and/or emphysema declined from 64.9 per 100,000 population to 47.6, while the rate increased from 13.6 to 20.9 for females.



      (a) Age standardised death rate per 100,000 of the total population as at 30 June 1991.
      (b) Based on the NHS classification (see Explanatory Notes, paragraph 14 in the publication).

DEATHS DUE TO MALIGNANT NEOPLASMS (CANCERS) OF THE TRACHEA, BRONCHUS AND LUNG

In addition to deaths due to respiratory conditions, there were 6,826 deaths due to malignant neoplasms (cancers) of the trachea, bronchus and lung, accounting for 5% of all deaths in 1996. Between 1981 and 1996, the male standardised death rate from this cause was consistently higher than the corresponding female rate. However, whilst the male standardised death rate declined by 20% (from 69.2 per 100,000 population in 1981 to 55.2 in 1996) the female rate increased by 55% (from 12.5 to 19.4).




      (a) Age standardised death rate per 100,000 of the total population as at 30 June 1991.
      (b) ICD code 162.

OTHER TABLES INCLUDED IN THIS PUBLICATION

Persons with respiratory conditions, by birthplace
Persons taking health-related actions
Persons, respiratory conditions, by sex and age group
Persons, respiratory conditions, by State and Territory
Persons, recent respiratory illnesses, by season
Adults, respiratory conditions, by sex and smoker status
Children, respiratory conditions, by sex and age group and smokers in household
Deaths due to respiratory conditions, 1996