Preventive antibiotics reduce infections but not mortality in adults with acute stroke
- Professor Peter Langhorne
Academic Section of Geriatric Medicine, Division of Cardiovascular and Neurological Sciences, University of Glasgow, Glasgow G4 0SF, UK;
Infection is a common complication in acute stroke1 and can affect patients with either cerebral infarction or cerebral haemorrhage. In most observational studies (such as those by Langhorne and colleagues2 and Aslanyan and colleagues3) the commonest post-stroke infections are of the chest (pneumonia) and of the urinary tract. These two infections can affect up to 20% of patients in the first few weeks after stroke.2 3 The main risk factors for such infections include general characteristics such as age, co- morbid illness and stroke severity and specific factors such as swallowing impairment and urinary catheter use.1 The development of infections appears to be associated with poorer outcomes. Pneumonia has been associated with an increased risk of death,4 and urinary tract infection is associated with increased levels of disability.3
Descriptive studies indicate that one distinctive characteristic of stroke unit care is active monitoring for and management of post-stroke infections.5 The prevention of post-stroke complications (especially infections) appears to explain at least part of the beneficial effect of stroke units on patient outcomes.6 Most acute stroke guidelines and acute stroke unit protocols advise on the prevention, early detection and early treatment of infections in patients but generally do not advise prophylactic administration of antibiotics.1 In view of the fact that early poststroke infections are common and are associated with poorer outcomes it was a logical step to consider the early prophylactic use of antibiotics.
This article describes a systematic review and metaanalysis of randomised trials of preventive antibiotics in patients with acute stroke. Although the authors used a rather limited trial search strategy and there is some lack of clarity on issues such as unbiased study selection and data extraction, in general the review methodology was good. The review identified four randomised trials (426 participants) that together indicated a potential beneficial effect of preventive antibiotic therapy. In particular, there was a significant reduction in early post-stroke infections and a trend towards a lower case-fatality rate. There were no reports of major harm or toxicity.
The results of this systematic review suggest that preventive antibiotic therapy may be promising, although it has not yet been demonstrated to improve patient survival or functional outcomes. It is also uncertain whether there is a significant risk of rare serious adverse events, such as significant infections with Clostridium difficile or methicillin-resistant Staphylococcus aureus.
The main clinical implication of this review is support for the current policies of active monitoring and management of infections in acute stroke patients. The main implication for research appears to be the need for larger multicentre randomised trials of preventive antibiotic therapy in acute stroke patients. At least one cluster randomised trial is currently under way in the UK to address this important topic. Until the results of such studies are available it would be premature to use routine preventive antibiotic therapy.
Competing interests None.