New-onset atrial fibrillation in bacteremia is not associated with C-reactive protein, but is an indicator of increased mortality during hospitalization.
BACKGROUND
Several studies have associated elevated C-reactive protein (CRP) levels to the occurrence of atrial fibrillation (AF). We sought to estimate the frequency and prognostic impact of AF in patients with bacteremia, and to study the possible association between AF and CRP as well as between AF and mortality in this population.


METHODS
We retrospectively evaluated patient charts of patients with bacteremia with Escherichia coli or Streptococcus pneumoniae admitted to the Aker University Hospital in Oslo between 1994 and 2004. Known cardiac risk factors for AF, signs and mode of conversion of AF, and, if applicable, date of death were registered, as were characteristics of infection, such as systemic inflammatory response syndrome and white blood cell count. Initial CRP values were categorized into 4 strata. Odds ratios of the 3 highest CRP categories compared with the lowest were obtained from logistic models adjusting for known cardiac risk factors for AF as well as possible factors that may have had an impact on the odds ratios for the different CRP levels. Cox regression analysis was used to compare new-onset AF and death during the first 2 weeks after hospitalization.


RESULTS
A total of 672 patient charts were studied; 104 patients (15.4%) had new-onset AF. Peak incidence of new-onset AF occurred on the day of admission. Peak CRP values were reached during the following 2 days. High CRP level at admission did not predict the occurrence of AF. The observed mortality was higher among patients with new-onset AF (p = 0.001) during the first 2 weeks after hospitalization, but this effect disappears when adjusted for relevant factors.


CONCLUSIONS
The frequency of new-onset AF in bacteremia is substantial. Initial CRP levels or white blood cell count do not seem to predict new-onset AF, as opposed to systemic inflammatory response syndrome. On the other hand, in patients with bacteremia, new-onset AF should be viewed as an indicator of increased mortality and morbidity.
Kindem
Ingvild A
IA
Division of Cardiology, Aker University Hospital and Faculty of Medicine, University of Oslo, Oslo, Norway.
Reindal
Eva K
EK
Wester
Astrid L
AL
Blaasaas
Karl G
KG
Atar
Dan
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000097:blood / Q000382:microbiology* / Q000401:mortality; D016470:Bacteremia / Q000150:complications*; D002097:C-Reactive Protein / Q000032:analysis*; D015331:Cohort Studies; D016208:Databases, Factual; D004926:Escherichia coli / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000150:complications*; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D016017:Odds Ratio; D011008:Pneumococcal Infections / Q000150:complications*; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D013296:Streptococcus pneumoniae / Q000302:isolation & purification
D002097:C-Reactive Protein