Air quality and respiratory disease in Newcastle, New South Wales

An observational study of PM10 and hospital admissions for acute exacerbations of chronic respiratory disease in Tasmania, Australia 1992-2002

Objective

Particulate matter with a diameter below 10 µ (PM₁₀) has been a major concern in the Tamar Valley, Launceston, where wood heaters are extensively used. We examined the relationship between PM₁₀ levels, meteorological variables, respiratory medications and hospital admissions for respiratory disease over the decade 1992–2002.

Methods

PM₁₀ levels were provided by the Department of Primary Industry Water, Parks and Environment, and meteorological variables from the Bureau of Meteorology. We obtained hospital discharge codes for the Launceston General Hospital. Poisson regression was used for statistical analyses.

Results

Mean daily PM₁₀ levels declined from 50.7 to 16.5 μg/m³. Hospitalisations for asthma decreased from 29 to 21 per month, whereas chronic obstructive pulmonary disease (COPD) increased and bronchitis/bronchiolitis remained unchanged. We found a 10 μg/m³ increase in PM₁₀ to be associated with a 4% increase in admissions for acute bronchitis/bronchiolitis (p0.05), but no association with asthma or COPD was found. All respiratory diseases showed seasonal patterns of hospitalisation.

Conclusions

This is the first long-term study in Australia to demonstrate an association between PM₁₀ levels and respiratory diseases. Reducing exposure to PM₁₀ may decrease hospital admissions for respiratory diseases.

Implication

Better preventive measures, including sustained public health initiatives to combat air pollution, are required to reduce respiratory morbidity.

Respiratory morbidity in hospitalized Bedouins residing near an industrial park

The residents' concern about exposure to a chemical industrial park (IP), which includes the national toxic industrial waste site, prompted the authors to initiate this ecological study on the association between residing near the IP and being hospitalized for respiratory ailments in the local Bedouin population. The population was stratified by sex, age, and locality type (permanent settlements and traditional tribal settlements). The distance and wind direction from the IP were used as exposure indicators. Hospitalization data were obtained from the regional medical center. Increased hospitalization rates for chronic obstructive pulmonary disease and all respiratory diseases were found to be associated with residential proximity to the IP. Attributable risk for chronic obstructive pulmonary disease was 34.2% in male members of the traditional tribal settlements and 49.3% in female members of the permanent settlements.

Effects of pollution on health of residents in an industrial area in Sri Lanka

The authors conducted a cross-sectional comparative prevalence study to evaluate the effect of pollution on individuals who lived in an industrial zone in Sri Lanka. In this study, 81 male and female children who were 1-12 yr of age and 158 adults (51 males, 107 females) in the industrial zone were matched with 73 children (32 males, 41 females) and 146 adults (58 males, 88 females), respectively, who lived in a nonindustrialized area and whose ages were similar to those of the exposed individuals. The authors used a pretested questionnaire and a detailed clinical examination, including peak expiratory flow rate measurements, to assess the prevalence of illness. Children in the industrial area were 2.3 times more likely to have unexplained episodic cough (95% confidence interval [CI] = 0.98, 10.3) and 2.8 times more likely to have rhinitis (95% CI = 1.1, 7.1). The adult population was 2.1 times more likely to have unexplained episodic cough (95% CI = 1.13, 7.09), 3.7 times more likely to have unexplained headaches (95% CI = 2.2, 6.3), and adults had a significantly greater reduction in expiratory flow (peak expiratory flow rate = 446 - 92x [industrial area] + 91x [male] - 0.8x [years lived in the area]).

Air pollution in the Latrobe Valley and its impact upon respiratory morbidity

OBJECTIVE

To assess the relationship between air pollution and respiratory morbidity.

DESIGN

An ecological study of the daily hospital admissions abstracted for the 1988 calendar year. Air quality data, including nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O3) and particulates, were obtained from the relevant authorities.

SETTING

Latrobe Valley, Victoria.

SUBJECTS

Hospital admissions for asthma and Chronic Obstructive Airways Disease. (COAD).

RESULTS

There were significant associations (r = 0.11 to 0.17) between airborne particles, nitrogen dioxide and respiratory morbidity. There was no significant relationship between any of the pollutants and asthma admissions. However, multi-variate analysis confirmed that NO2 and particulates were associated with admissions for COAD.

CONCLUSION

Respiratory morbidity appears to be affected even by the low air pollution levels in the Latrobe Valley.

Childhood antecedents of adult respiratory disease

This review examines the relations between early childhood lower respiratory symptoms and adult respiratory disease. The problems associated with investigating potential associations between respiratory disease in children and adults are discussed. Some studies have limitations because they are retrospective and early childhood respiratory symptoms have not been accurately diagnosed. Therefore, in this review, particular attention is paid to longitudinal studies (some from birth) that have used strict diagnostic criteria for respiratory episodes. These studies provide unique insights into the risk factors for the development of childhood respiratory problems and for persistence of symptoms into adulthood. Although cross-sectional studies have indicated that early childhood respiratory disease is more frequent in adults with respiratory disease, evidence from longitudinal studies suggests that respiratory symptoms such as wheezing, are transient in the majority of infants and result from developmentally small airways. These longitudinal investigations have also indicated that persistence of symptoms into later childhood is associated with atopy. The important role of cigarette-smoke exposure as a risk factor for abnormal pulmonary development, persistence of respiratory disease and reduction in lung function is discussed. The discovery of genetic markers associated with respiratory syndromes such as asthma, should facilitate studies that investigate the childhood antecedents of adult respiratory disease. Future longitudinal studies using genetic markers, will allow relations between specific genotypes and phenotypic outcomes to be examined.