Background: The impact of total body weight (TBW) on 30-day mortality associated with gram-negative bacteremia has not been previously evaluated.
Methods: The cohort included 323 patients >/ = 18 years old with gram-negative bacteremia (1/1/2008-8/31/2011) who received >/ = 48 hours of antibiotics. We compared 30-day mortality of TBW <70 kg vs. >/ = 70 kg with a multivariable stepwise logistic regression adjusting for age >/ = 70 years, cancer diagnosis, and Pitt bacteremia score of >/ = 4.
Results: The cohort was 57% TBW >/ = 70 kg and 43% TBW <70 kg. TBW >/ = 70 kg patients had lower 30-day mortality (11.0% vs. 16.3%), which was significant in the multivariable analysis (OR 0.45, 95% CI 0.21-0.97). Cancer and Pitt bacteremia score >/ = 4 were also independently associated with 30-day mortality. TBW was no longer significant when TBW <50 kg patients were excluded.
Conclusion: TBW >/ = 70 kg was associated with an improved 30-day mortality; however, the high mortality rates for patients with a TBW < 50 kg is responsible for this association.
Keywords: Escherichia coli; Gram-negative; Klebsiella sp; bacteremia; total body weight.