- Aspirin use was associated with a reduced risk of ischaemic stroke and myocardial infarction (MI) in primary care patients who developed pneumonia.
Why this matters
- Future research should focus on the potential use of aspirin in patients with newly diagnosed pneumonia, and whether the risk-benefit balance is shifted in the short-term in favour of aspirin prophylaxis.
- This prior event rate ratio analysis with propensity score matching included 48,743 patients with pneumonia (age, >50 years) from the UK Clinical Practice Research Datalink (CPRD).
- 9468 aspirin users were matched with 9468 non-aspirin users.
- Primary outcome: combined outcome of ischaemic stroke and MI; secondary outcomes: ischaemic stroke and MI individually.
- Funding: National Institute for Health Research.
- Aspirin use was associated with a reduced risk of the combined primary outcome of ischaemic stroke and MI (adjusted HR [aHR], 0.64; 95% CI, 0.52-0.79) compared with no use.
- For both secondary outcomes, aspirin use was associated with a reduced risk of:
- ischaemic stroke (aHR, 0.70; 95% CI, 0.55-0.91); and
- MI (aHR, 0.46; 95% CI, 0.30-0.72).
- In Cox regression analysis, aspirin reduced the risk of the primary outcome (HR 0.84; 95% CI, 0.73–0.96) and stroke (HR, 0.80; 95% CI, 0.68-0.96), with weaker evidence of a reduction in MI (HR, 0.82; 95% CI, 0.66–1.02).
- Risk of confounding.