This finding raises an issue of public health importance because of the large number of elderly patients in the United Kingdom who are treated for glaucoma.
Researchers in London identified patients with no previous diagnosis of airways obstruction. They defined exposed patients as those who had used topical ß blockers for the first time in the period 1993-7. Unexposed patients were randomly selected and matched for age and sex to exposed patients.
One year after treatment with topical ß blockers, the authors calculated that 55 patients would need to be treated to cause one case of airways obstruction during that time period.
Opthalmologists, general practitioners, physicians, and pharmacists need to be aware of the possibility of airways obstruction in patients taking topical ß blockers for glaucoma, say the authors. When eyesight cannot be threatened within their expected lifetime, many frail elderly patients may be better off left untreated than risk airways obstruction.
ß blockers should be discontinued immediately when a patient develops airways obstruction and their opthalmologist subsequently informed. A repeat prescription that includes topical ß blockers and drugs for asthma should automatically sound an alarm, they conclude.