Analysis using life tables of the major causes of death and the differences between country of birth groups in New South Wales, Australia

OBJECTIVES

This study used life table methods to evaluate the potential effects of reduction in major disease mortality on life expectancy in New South Wales (NSW), and the differences in cause-specific mortality between country of birth groups. The total and partial elimination of major causes of death were examined to identify the high-risk groups for community-level health planning.

STUDY DESIGN

Life tables were used to combine the mortality rates of the NSW population at different ages into a single statistical model.

METHODS

Using abridged, multiple decrement and cause-elimination life tables with the mortality data for NSW in 2000-2002, broader disease groups were examined. Multiple decrement tables were generated by country of birth. The effect of the partial elimination of ischaemic heart disease (IHD) was also studied.

RESULTS

This study found that Pacific-born men and women who reach their 30th birthday and eventually die from IHD are expected to live, on average, 10.8 and 5.8 years less, respectively, than average men and women in NSW. If IHD is eliminated as a cause of death, 7.5 years for males and 6.7 years for females would be added to life expectancy at birth.

CONCLUSIONS

Life expectancy at birth is likely to be further increased by reducing deaths caused by diseases of the cardiovascular system, particularly among people aged over 65 years, by reducing malignant neoplasm deaths among those aged below 65 years, and by reducing deaths due to accidents, injury and poisoning, mainly among men aged 15-29 years. Further gains in life expectancy could be achieved with community-level educational programmes on lifestyle management and disease prevention.

Coronary artery bypass graft surgery trends in New South Wales, Australia

OBJECTIVE

The main objective of this study was to assess the trends in coronary artery bypass graft (CABG) rates in New South Wales (NSW), Australia over a 12-year period beginning in mid-1990. These rates were examined in relation to the patients' age, gender, complications and length of stay in the hospital.

METHODS

Data pertaining to the CABG surgeries performed among 72668 patients were extracted from the hospital inpatient statistics of the NSW Department of Health. The study covered all public and private hospitals in NSW. The indirect standardization technique and logistic regression modelling were used to analyse the data.

RESULTS

CABG rates increased with age, peaked in the age range 65-79 years and then declined with age. The median age of the patients showed an increasing trend. While women were less likely to have a CABG, they were substantially older than men at the time of surgery. The predictors of extended post-surgery length of stay were age, insulin-dependent diabetes, acute and chronic renal failure, congestive heart failure, pulmonary disease and having more than three vein grafts.

CONCLUSION

An increasing trend in older patients indicates the improvements in skills of cardiothoracic surgeons and the advancement in technology, which have enabled the doctors to treat those patients who were unable to have the surgery previously.

Seasonality of coronary artery deaths in New South Wales, Australia

BACKGROUND

Complex temporal variations in coronary deaths, including diurnal, weekly, and seasonal trends, have been reported worldwide.

OBJECTIVE

To describe the magnitude of seasonal changes in coronary artery deaths in New South Wales, Australia.

DESIGN

Hospital morbidity data, mortality statistics, and meteorological data were modelled using time series techniques to determine seasonality of coronary deaths. Data were also analysed to determine whether there was an increase in deaths before or after the Christmas and New Year holidays.

RESULTS

A clear seasonality of coronary deaths was shown, with a peak in July. A mean of 2.8 excess coronary deaths per 100 deaths was estimated to occur from June to August each year, with a mean annual excess of 224 winter deaths a year. Mortality data did not show an increase in coronary death ratios before (p = 0.626) or after (p = 0.813) the Christmas and New Year holidays in December.

CONCLUSIONS

There is a higher incidence of coronary deaths in winter, which may reflect winter respiratory infections, the direct effect of cold, seasonal changes in lipid concentration, and other factors associated with winter. Hospitals should have contingency plans during the winter months to manage larger numbers of cardiac admissions.