Mortality after infection with methicillin-resistant Staphylococcus aureus (MRSA) diagnosed in the community

BMC Med. 2008 Jan 31;6:2. doi: 10.1186/1741-7015-6-2.

Abstract

Background: Outbreak reports suggest that community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections can be life-threatening. We conducted a population based cohort study to assess the magnitude of mortality associated with MRSA infections diagnosed in the community.

Methods: We used the United Kingdom's General Practice Research Database (GPRD) to form a cohort of all patients with MRSA diagnosed in the community from 2001 through 2004 and up to ten patients without an MRSA diagnosis. The latter were frequency-matched with the MRSA patients on age, GPRD practice and diagnosis date. All patients were older than 18 years, had no hospitalization in the 2 years prior to cohort entry and medical history information of at least 2 years prior to cohort entry. The cohort was followed up for 1 year and all deaths and hospitalizations were identified. Hazard ratios of all-cause mortality were estimated using the Cox proportional hazards model adjusted for patient characteristics.

Results: The cohort included 1439 patients diagnosed with MRSA and 14,090 patients with no MRSA diagnosis. Mean age at cohort entry was 70 years in both groups, while co-morbid conditions were more prevalent in the patients with MRSA. Within 1 year, 21.8% of MRSA patients died as compared with 5.0% of non-MRSA patients. The risk of death was increased in patients diagnosed with MRSA in the community (adjusted hazard ratio 4.1; 95% confidence interval: 3.5-4.7).

Conclusion: MRSA infections diagnosed in the community are associated with significant mortality in the year after diagnosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • Community-Acquired Infections / diagnosis
  • Community-Acquired Infections / microbiology
  • Community-Acquired Infections / mortality*
  • Humans
  • Methicillin Resistance*
  • Sensitivity and Specificity
  • Staphylococcal Infections / diagnosis
  • Staphylococcal Infections / microbiology
  • Staphylococcal Infections / mortality*
  • Staphylococcus aureus / isolation & purification*