Demographic characteristics of asthma admissions to hospitals.

The age, sex, race, domicile and geographic distribution of patients admitted to hospital for asthma in New Zealand in 1981 were studied. The 0-14 year age group had a higher admission rate than the older age group. Males were admitted more frequently than females in the youngest and eldest age groups, but the converse was found in the 15-64 year age group. The Polynesian admission rates were more than double those of Europeans in all age groups. The effect of urban or rural domicile on asthma admission rates is age dependent. Urban dwellers under 25 years of age have higher admission rates than those with rural domiciles, however, in those over 45 there is a higher admission rate from rural areas than from urban areas. There was a highly significant difference in the admission rates between hospital boards (p = 0.003). For hospital boards serving populations of 50,000 or more there was a 9 fold difference between the highest (Hawkes Bay) and lowest (Nelson) admission rates. The geographical distribution of asthma admission rates show distinct areas with high (south of the North Island) and low (Auckland and Waikato) rates. The national admission rates almost doubled between 1976 and 1981 and the spatial pattern of admission rates was similar in these two years (r = 0.627 p less than 0.001). This indicates that the increase in admissions occurred uniformly throughout the country.