The impact of aging on the incidence and mortality rate of bloodstream infection: a hospital-based case-cohort study in a tertiary public hospital of Brazil

Trop Med Int Health. 2021 Jul 4. doi: 10.1111/tmi.13650. Online ahead of print.


OBJECTIVE: Over the past few decades, life expectancy in Brazil has increased from 48 years in 1950s to 76 years in 2017. The aim of this study was to investigate the impact of aging on: 1) the frequency of hospitalizations due to bloodstream infection (BSI); 2) the incidence of hospital-acquired BSI (H-BSI); 3) the incidence of multidrug resistant (MDR) agents BSI; 4) the mortality rate of BSI in a public hospital.

METHODS: A hospital-based case-cohort study was conducted between December 1st , 2013, and December 31st , 2015. The data were analyzed using multivariable logistic regression.

RESULTS: A total of 500 BSI episodes were detected, among 11,102 hospitalizations. The incidence of hospitalizations resulting from BSI were significantly higher in older than younger patients (3.7/100 vs 2.0/100, p<0.01). Similarly, the incidence of hospital-acquired BSI was significantly higher in older patients (2.7/100 vs 0.9/100, p<0.01). Klebsiella pneumoniae (15.9%), Staphylococcus aureus (14.3%), Escherichia coli (13.1%) and Acinetobacter spp. (12.1%) were the most common agents isolated. MDR agents caused 37.6% of the BSI episodes; Enteric Gram-negative bacilli resistant to 3rd /4th generation cephalosporins (9.7%) and carbapenem-resistant Acinetobacter spp. (9.2%) were the most common MDR agents. The following complications were independently associated with aging: Charlson comorbidity index (OR = 1.16; 95%CI = 1.09-1.24); BSI secondary to urinary tract infection (OR = 2.14; 95%CI = 1.29-3.55); BSI secondary to pneumonia (OR = 1.77; 95%IC = 1.07-2.93) and 30-day mortality following BSI (OR = 2.19; 95%CI = 1.43-3.36) CONCLUSIONS: These data suggest aging has a significant impact on hospitalizations due to BSI, H-BSI incidence, and mortality from BSI in older patients attending a Brazilian public hospital. Age was not significantly associated with MDR-related BSI. These results indicate that age plays an important role in the increase in morbidities and mortality resulting from BSI in Brazil and that with the increased life expectancy observed over recent decades in Brazil, the burden of BSI will be expected to continue to increase. This dynamic needs to be better understood with additional studies.

PMID:34218504 | DOI:10.1111/tmi.13650