Complications

Accumulating evidence indicates a frequent association between CAP and acute cardiac complications, including atrial fibrillation, HF and myocardial infarction.¹ Multiple clinical studies have reported a 2- to eightfold increase in CVD risk within first 30 days after respiratory infections.² CV complications develop in up to 30% of patients hospitalised for CAP, even up to 10 years thereafter.³ Among patients with pneumonia, acute myocardial infarction or unstable angina is reported in 5% of cases, new-onset arrhythmias in 12% cases and chronic heart failure in 14% cases. Studies have identified several risk factors for CV events in patients with CAP, such as older age, pre-existing CV or chronic respiratory conditions, hospital-stay, older age, severity of CAP and smoking.⁴

A matched cohort study investigated whether hospitalisation due to pneumonia was associated with increased risk of CVD. The study reported that pneumonia-related hospitalisation is associated with increased short-term (up to 1 year) and long-term (10 years) CVD risk, thereby indicating that pneumonia is a risk factor for CVD.² Another multicentre study prospectively followed 1182 hospitalised patients with CAP for up to 30 days for CV events. The study reported intrahospital CV events in 32.2% of patients with CAP, while 2.4% patients died because of CV causes. The study revealed that CV events occur in around one-third of patients hospitalised for CAP, and such events are associated with a fivefold increase in CAP-associated mortality within 30 days.¹

A recent retrospective observational study reported that patients with CVD are at higher risk of both CAP and HAP, and have higher frequency of ICU admissions. Additionally, regardless of comorbidities, age, gender and antibiotic use, pneumonia risk was particularly associated with HF, especially in elderly male patients.⁵ 
Another recent systematic review and meta-analysis of 39 studies involving 92,188 patients revealed that overall cardiac complications occurred in 13.9% of CAP cases. Heart failure was observed in 7.2% of pooled patients, while acute coronary syndromes, arrhythmias and stroke occurred in 4.5%, 7.2% and 0.71% of patients with CAP, respectively.⁶

CAP, community-acquired pneumonia; CV, cardiovascular; CVD, cardiovascular disease; HAP, hospital-acquired pneumonia; HF, heart failure; ICU, intensive coronary unit.

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