We aimed to assess the risk of cardiovascular hospitalisations (stroke or myocardial infarction (MI)) following a community-acquired pneumonia (CAP) hospitalisation in a large Portuguese administrative dataset.

Self-controlled case series study.

We used hospitalisation data from National Health Service hospitals across Portugal between 2010 and 2018.

Adults hospitalised for both CAP and stroke/MI in Portugal during the 2010-2018 period (n=13 494, of which 10 400 with stroke and 3094 with MI).

We considered CAP hospitalisation as the exposure (14-, 28- and 91-day exposure periods) and acute cardiovascular (stroke or MI) hospitalisations as the outcome. Incidence rate ratios (IRR) were computed using a conditional Poisson regression (overall and by sex and age subgroups).

Patients were mostly male and above 75 years. Stroke/MI hospitalisation incidence was higher following CAP, compared with the baseline period. Largest differences were observed in the 14-day period after discharge (IRR for stroke: 2.55, 95% CI: 2.33–2.80; IRR for MI: 3.23, 2.78–3.75), compared with the 28-day (IRR for stroke: 2.06, 1.92–2.22; IRR for MI: 2.62, 2.32–2.95) and 91-day periods (IRR for stroke: 1.37, 1.30–1.44; IRR for MI: 1.75, 1.60–1.91). A similar trend was observed for sex and age subgroups.

Our study shows an increased risk of stroke/MI for CAP patients, particularly during the first 2 weeks after being discharged. Effective postdischarge monitoring and follow-up, combined with efforts to prevent CAP occurrence, could improve patient outcomes.