title: Infection-related hospitalizations in breast cancer patients: Risk and impact on prognosis.
abstract: Infections are a common cause of hospitalization in breast cancer patients. We studied the risk, clinical characteristics and outcomes of infection-related hospitalizations in this patient population.
  
  
  
  A Swedish registry-based study including 8338 breast cancer patients diagnosed between 2001 and 2008, followed prospectively for infection-related hospitalizations until 2010. Standardized incidence ratios (SIRs) were calculated using background rates from the general female population. Associations with clinical characteristics and mortality were analyzed using flexible parametric survival models.
  
  
  
  In total, 720 patients experienced an infection-related hospitalization during a median follow-up of 4.9 years. Infection rates were highest within the first year of diagnosis (SIR = 5.61, 95% CI; 4.98-6.32), and site-specific risks were most pronounced for sepsis (SIR = 3.14, 95% CI; 2.66-3.71) and skin infections (SIR = 2.80, 95% CI; 2.24-3.50). Older age at diagnosis, comorbidities, markers of tumor aggressiveness, chemotherapy and axillary node dissection were independent predictors of infectious disease risk. Infection-related hospitalizations were also independently associated with overall and breast cancer-specific death.
  
  
  
  A significant number of breast cancer patients are hospitalized with an infection following diagnosis, which in turn predicts poor prognosis. The risk profile of infection-related hospitalizations is multifactorial, including patient, tumor and treatment-related factors.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. Electronic address: judith.brand@ki.se.
authors.forename: Judith S
authors.initials: JS
authors.lastname: Brand
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Colzani
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Anna L V
authors.initials: ALV
authors.lastname: Johansson
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Johan
authors.initials: J
authors.lastname: Giesecke
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Mark
authors.initials: M
authors.lastname: Clements
authors.affiliation: Department of Oncology-Pathology, Radiumhemmet, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Bergh
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Hall
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Kamila
authors.initials: K
authors.lastname: Czene
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000150:complications* / Q000188:drug therapy / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007239:Infections / Q000453:epidemiology* / Q000209:etiology; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology
keywords: Breast cancer; Epidemiology; Infection-related hospitalizations; Prognosis; Risk factors