Intensive care unit (ICU)-acquired bacteraemia and ICU mortality and discharge: addressing time-varying confounding using appropriate methodology.
J Hosp Infect
; 99(1): 42-47, 2018 May.
Article
em En
| MEDLINE
| ID: mdl-29175434
ABSTRACT
BACKGROUND:
Studies often ignore time-varying confounding or may use inappropriate methodology to adjust for time-varying confounding.AIM:
To estimate the effect of intensive care unit (ICU)-acquired bacteraemia on ICU mortality and discharge using appropriate methodology.METHODS:
Marginal structural models with inverse probability weighting were used to estimate the ICU mortality and discharge associated with ICU-acquired bacteraemia among patients who stayed more than two days at the general ICU of a London teaching hospital and remained bacteraemia-free during those first two days. For comparison, the same associations were evaluated with (i) a conventional Cox model, adjusting only for baseline confounders and (ii) a Cox model adjusting for baseline and time-varying confounders.FINDINGS:
Using the marginal structural model with inverse probability weighting, bacteraemia was associated with an increase in ICU mortality (cause-specific hazard ratio (CSHR) 1.29; 95% confidence interval (CI) 1.02-1.63) and a decrease in discharge (CSHR 0.52; 95% CI 0.45-0.60). By 60 days, among patients still in the ICU after two days and without prior bacteraemia, 8.0% of ICU deaths could be prevented by preventing all ICU-acquired bacteraemia cases. The conventional Cox model adjusting for time-varying confounders gave substantially different results [for ICU mortality, CSHR 1.08 (95% CI 0.88-1.32); for discharge, CSHR 0.68 (95% CI 0.60-0.77)].CONCLUSION:
In this study, even after adjusting for the timing of acquiring bacteraemia and time-varying confounding using inverse probability weighting for marginal structural models, ICU-acquired bacteraemia was associated with a decreased daily ICU discharge risk and an increased risk of ICU mortality.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Infecção Hospitalar
/
Bacteriemia
/
Unidades de Terapia Intensiva
Tipo de estudo:
Etiology_studies
/
Incidence_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Adult
/
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
País/Região como assunto:
Europa
Idioma:
En
Revista:
J Hosp Infect
Ano de publicação:
2018
Tipo de documento:
Article