Recent trends in asthma mortality, morbidity, and management in New Zealand.

Trends in mortality and hospital admission rates, prevalence, and drug sales, relating to asthma in New Zealand since 1960 were examined. Two epidemics of asthma death among people in the age range of 15-64 years occurred during this period with peak mortality rates more than four times pre-epidemic rates. Death from asthma was nevertheless rare compared with hospital admissions which have increased 20-fold in children and three- to fivefold in adults between 1960 and 1985. Asthma drug sales have also risen dramatically, particularly in the late 1970s when it is likely that a major change in the drug management of asthma occurred. Changes in asthma prevalence and severity may account in part for the increasing hospital admissions rates. However, the lack of any clear relationship between hospital admissions and death rates and the abrupt time course of the mortality epidemics suggest that changes in the management rather than in the disease itself may be responsible for the increased number of asthma deaths.