Changing patterns of hospital admission for asthma, 1981-97

Background-Hospital admission rates for asthma have stopped rising in sever al countries. The aim of this study was to use linked hospital admission da ta to explore recent trends in asthma admissions in Scotland. Methods-Linked Scottish Morbidity Records (SMR1) for asthma (ICD-9 493 and ICD-10 J45-6) from 1981 to 1997 were used to describe rates of first admiss ions and readmissions by age and sex. As a measure of resource use, annual trends in bed days used were also explored by age and sex. Results-There were 160 039 hospital admissions for asthma by 82 421 individ uals in Scotland during the study period. The overall hospital admission ra te increased by 122% (from 106.7 to 236.7 per 100 000 population) but this varied by sex, age, and admission type. First admissions rose by 70% from 7 3.2 per 100 000 in 1986 to 124.8 per 100 000 in 1997 while readmissions fel l. Children (< 15 years) experienced a decline in overall admissions after 1992 due to falls in both new admissions and readmissions. By 1997 the rati o of female to male admissions was 0.57 in children, but 1.50 above 14 year s of age. Mean lengths of stay fell from 10.7 days to 3.7 days between 1981 and 1997 and bed days used showed little change except for a decline after 1992 in children. Conclusions-After a period of increasing hospitalisation for asthma in Scot land, rates of admission among children have begun to fall but among adults admissions continue to rise.