Prescribing of beta-2 agonists and inhaled steroids in England: trends between 1992 and 1998, and association with material deprivation, chronic illness and asthma mortality rates.

BACKGROUND

British Thoracic Society guidelines published in 1990, revised in 1993 and 1997, recommended that general practitioners should make greater use of inhaled steroids in the management of asthma. British Thoracic Society guidelines have also been published on the management of chronic obstructive pulmonary disease. The objective of this study was to examine trends in the prescribing of beta-2 agonists and inhaled steroids in England between 1992 and 1998, and to investigate the variation at health authority level in the use of these drugs.

METHODS

This was an observational study using prescribing analysis and cost (PACT) data, mortality data and data from the 1991 Census for all 100 health authorities in England.

RESULTS

The number of defined daily doses of beta-2 agonists prescribed per quarter increased by 20 per cent, from 142 million to 170 million between June 1992 and March 1998. The number of defined daily doses of inhaled steroids prescribed per quarter increased by 78 per cent during the same period, from 69.9 million to 124.7 million. The ratio of inhaled steroids to beta-2 agonists increased from 0.49 to 0.73. The number of items per 1000 specific therapeutic group age-sex related prescribing units (STAR-PUs) in 1997 in health authorities in England varied from 41 to 115 for beta-2 agonists and from 24 to 68 for inhaled steroids. The ratio of the number of items of inhaled steroids to beta-2 agonists varied from 0.50 to 0.70. At health authority level, prescribing rates were most strongly associated with the percentage of patients reporting chronic illness (correlation coefficient 0.82 for beta-2 agonists and 0.72 for inhaled steroids). There were significant negative correlations between the ratio of inhaled steroids to beta-2 agonists and both Jarman deprivation scores (r = -0.51) and chronic illness (r = -0.38). There were no significant associations between health authority prescribing rates and death rates from asthma in people aged 5-44 years.

CONCLUSIONS

Prescribing of inhaled steroids has risen more quickly than that of beta-2 agonists between 1992 and 1998, resulting in a marked increase in the ratio of inhaled steroids to beta-2 agonists. At health authority level, there remains a wide variation in the use of beta-2 agonists and inhaled steroids.