Hospital admissions and attendances for asthma--a true increase?

To compare the ratio of hospital admissions for asthma to total hospital admissions and to admissions for non-asthma respiratory conditions, over an 11-year period, to see if there has been a true increase in admissions for asthma or merely a change in diagnostic labelling. A similar comparison was made for presentations with asthma and non-asthma respiratory conditions to the accident and emergency department.

A case review of all patients with a confirmed diagnosis of respiratory disease admitted to hospital or attending the accident and emergency department at the Camperdown Children's Hospital between 1979 and 1989.

There was a 98% increase in the number of patients admitted with a confirmed diagnosis of asthma. While the ratio of admissions for asthma to total admissions increased from 0.053 in 1979 to 0.09 in 1989, the ratio of admissions for non-asthma respiratory conditions to total admissions remained relatively constant. The ratio of attendances for asthma to total accident and emergency attendances rose from 0.017 in 1979 to 0.072 in 1989, whereas the ratio of attendances for non-asthma respiratory conditions to total accident and emergency attendances had a maximum variation of 0.065 to 0.09.

These results suggest that there has been a major increase in the number of cases of asthma being treated at this hospital and that this is a true increase, perhaps representing increased severity, rather than a change in diagnostic labelling.