Cardiac complications in pneumonia patients linked to mortality
MedWire News: Cardiac complications are common in patients with community-acquired pneumonia (CAP) and are associated with increased short-term mortality, research suggests.
Clinicians must realize the importance of incident cardiac complications in CAP patients and exercise appropriate clinical alertness for timely recognition, recommend Vicente Corrales-Medina (University of Ottawa, Ontario, Canada) and co-authors in Circulation.
Their analysis included 1343 inpatients and 944 outpatients with CAP (defined as the presence of one or more pneumonia symptoms and radiographic evidence within 24 hours of presentation), who were followed for 30 days after presentation.
Patients were  assessed for the severity of pneumonia using the Pneumonia Severity Index (PSI), which classified them into one of five risk groups based on estimated 30-day mortality, ranging from 0.1% for Class I (lowest risk) to 27.0% for Class V (highest risk).
The researchers followed up all patients for three incident cardiac complications: new or worsening heart failure, new or worsening arrhythmias, and myocardial infarction (MI).
Incident cardiac complications were diagnosed in 358 (26.7%) inpatients and 20 (2.1%) outpatients. Most (89.1% in inpatients, 75% in outpatients) events were diagnosed within the first week and over half of them were recognized in the first 24 hours.
Factors associated with cardiac complications included older age (mean age was 73 years in those with complications vs 53 years in those without), nursing home residence, and pre-existing cardiovascular conditions (heart failure, arrhythmias, coronary heart disease, arterial hypertension; p<0.01 for all).
A respiratory rate of at least 30 breaths per minute, various laboratory or radiographic abnormalities, and site of care were also associated with cardiac complications (p<0.01 for all).
After excluding patients who died on the day of presentation, the factors that remained significantly associated with cardiac complications were older age, nursing home residence, history of heart failure, arterial hypertension, blood pH less than 7.35, hematocrit less than 30%, and inpatient status.
Baseline PSI score was significantly higher in patients who developed cardiac complications compared with those who did not, at 114 versus 63 (p<0.01). In addition, there was a significant increasing trend across PSI risk classes, ranging from 1.2% for Class I to 47.4% for Class V (p<0.01 for trend).
Of note, 30-day mortality was significantly higher in patients with CAP who developed cardiac complications compared with those who did not, at 15.3% of 58 patients with complications versus 2.8% of 53 patients without complications (p<0.01). This association remained significant even after adjusting for baseline PSI score.
The authors propose that health officials increase efforts to optimize the rates of influenza and pneumococcal vaccination among the elderly and those with chronic cardiac conditions to reduce the incidence of pneumonia in these high-risk groups.
"The prevention and optimal management of these events may significantly reduce the burden of death associated with this infection," they add.
Corrales-Medina and team conclude: "Further research is required to test risk stratification, prevention and treatment strategies for incident cardiac complications in patients with CAP."
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By Piriya Mahendra