Staphylococcus aureus bloodstream infections: the association between age and mortality and functional status.
OBJECTIVE
To assess the association between Staphylococcus aureus (S. aureus) blood stream infections (BSIs) and morbidity and mortality in older adults.


METHODS
Retrospective review.


METHODS
Veterans Affairs Ann Arbor Healthcare System.


METHODS
All patients with S. aureus BSI during 2004/05.


METHODS
Outcomes included in-hospital and 6-month mortality, as well as need for subacute care.


RESULTS
Sixty-eight patients with S. aureus BSI were identified (mean age 63.5+/-13.0). Outcomes of interest included in-hospital mortality (19.1%), 6-month mortality (33.8%), and need for subacute care (65.4%). Univariate analysis identified several predictors of death, including older age, chronic renal insufficiency, catheter-related infection, Charlson weighted index of comorbidity score, and infection with methicillin-resistant S. aureus (MRSA). Multivariable analysis demonstrated that older age (odds ratio (OR)=1.1, P<.01), chronic renal insufficiency (OR=16.6, P=.01), and MRSA infection (OR=5.1, P=.03) were independently associated with 6-month mortality. These results suggest that, for every decade increase in age, the odds of death within 6 months of S. aureus BSI doubles (OR=1.1). Chronic renal insufficiency was also independently associated with in-hospital mortality. Of the previously community-dwelling patients (n=50), 41 survived hospitalization, of whom 22 (53.7%) required subacute care after discharge.


CONCLUSIONS
Better understanding of the epidemiology of S. aureus BSI in older patients and validation of risk factors for poor functional outcomes and death should be the focus of future prospective studies.
Malani
Preeti N
PN
Department of Internal Medicine, Division of Infectious , Ann Arbor Veterans Affairs Healthcare System, University of Michigan Health System, Ann Arbor, Michigan 48105, USA. pmalani@umich.edu
Rana
Meenakshi M
MM
Banerjee
Mousumi
M
Bradley
Suzanne F
SF
D000203:Activities of Daily Living / Q000145:classification*; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000401:mortality*; D015897:Comorbidity; D003428:Cross Infection / Q000401:mortality*; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D015577:Geriatric Assessment; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D016106:Methicillin Resistance; D008824:Michigan; D008875:Middle Aged; D016017:Odds Ratio; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000401:mortality*; D013211:Staphylococcus aureus / Q000187:drug effects; D016019:Survival Analysis