Relationship between neighborhood poverty rate and bloodstream infections in the critically ill

Mendu ML et al. – Within the limitations of the study design, increased neighborhood poverty rate, a proxy for decreased socioeconomic status, appears to be associated with risk of bloodstream infection among patients who receive critical care.

Methods

• The authors performed a multicenter observational study of 14,657 patients, aged 18yrs or older, who received critical care and had blood cultures drawn between 1997 and 2007 in two hospitals in Boston, Massachusetts.
• Data sources included 1990 U.S. Census and hospital administrative data. Census tracts were used as the geographic units of analysis.
• The exposure of interest was neighborhood poverty rate categorized as <5%, 5%–10%, 10%–20%, 20%–40%, and >40%.
• Neighborhood poverty rate is the percentage of residents with income below the federal poverty line.
• The primary end point was bloodstream infection occurring 48hrs before critical care initiation to 48hrs after.
• Associations between neighborhood poverty rate and bloodstream infection were estimated by logistic regression models.
• Adjusted odds ratios were estimated by multivariable logistic regression models.

Results

• Two thousand four-hundred thirty-five patients had bloodstream infections.
• Neighborhood poverty rate was a strong predictor of risk of bloodstream infection, with a significant risk gradient across neighborhood poverty rate quintiles.
• After multivariable analysis, neighborhood poverty rate in the highest quintiles (20%–40% and >40%) were associated with a 26% and 49% increase in bloodstream infection risk, respectively, relative to patients with neighborhood poverty rate of <5%.

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