title: Incidence of skin and soft tissue infections in ambulatory and inpatient settings, 2005-2010.
abstract: BACKGROUND
  The emergence of community-associated methicillin-resistant S. aureus was associated with dramatically increased skin and soft tissue infection (SSTI) incidence in the first few years of the 21(st) century in the U.S. However, subsequent trends are poorly understood.
  
  
  METHODS
  We examined ambulatory and inpatient data of over 48 million persons years aged 0-64 years from the HealthCore Integrated Research Database (HIRD) between 2005 and 2010. Data were extracted from medical, pharmacy, and eligibility databases. We quantified SSTI incidence, type, and complications and comparative incidence trends for urinary tract infections (UTIs) and pneumonia.
  
  
  RESULTS
  A total of 2,301,803 SSTIs were identified. Most SSTIs (95 %) were treated in the ambulatory setting and most (60 %) were categorized as abscesses or cellulitis. During the study period, SSTI incidence remained relatively stable from 47.9 (95 % CI: 47.8-48.1) cases/1,000 PY in 2005 to 48.5 cases/1,000 PY (95 % CI: 48.3-48.6) in 2010). Persons aged 45-64 years had the highest incidence of both ambulatory-treated and inpatient-treated SSTIs (51.2 (95 % CI: 51.1-51.3) and 3.87 (95 % CI: 3.84-3.90) cases/1,000 PY, respectively). SSTI complications such as myositis, gangrene, and sepsis occurred in 0.93 % (95 % CI: 0.92-0.94 %) and 16.92 % (95 % CI: 16.87-16.97 %) of ambulatory-treated and inpatient-treated patients, respectively. SSTI incidence was approximately twice that of UTIs and tenfold of that of pneumonia.
  
  
  CONCLUSIONS
  Among our large, diverse population of persons less than 65 years, SSTI incidence 2005 through 2010 has remained relatively constant at approximately 4.8 SSTIs per 100 person years, suggesting that previously observed increases in SSTI incidence remain sustained.
authors: Infectious Disease Clinical Outcomes Research Unit (ID-CORE), Division of Infectious Diseases, Los Angeles BioMedical Research Center at Harbor-UCLA, Torrance, CA, USA. Lgmiller@ucla.edu.|Division of Infectious Diseases, Harbor-UCLA Medical Center, 1000 W Carson St Box 466, Torrance, CA, 90509, USA. Lgmiller@ucla.edu.|David Geffen School of Medicine at UCLA, Los Angeles, USA. Lgmiller@ucla.edu.
authors: Loren G
authors: LG
authors: Miller
authors: HealthCore, Inc, Wilmington, DE, USA. DEisenberg@healthcore.com.
authors: Debra F
authors: DF
authors: Eisenberg
authors: Division of Public Health, School of Dentistry at UCLA, Los Angeles, USA. hhliu@dentistry.ucla.edu.|Division of General Internal Medicine, David Geffen School of Medicine at UCLA, Los Angeles, USA. hhliu@dentistry.ucla.edu.|Department of Biostatistics, Fielding School of Public Health at UCLA, Los Angeles, USA. hhliu@dentistry.ucla.edu.
authors: Honghu
authors: H
authors: Liu
authors: HealthCore, Inc, Wilmington, DE, USA. ginaclc@hotmail.com.
authors: Chun-Lan
authors: CL
authors: Chang
authors: Department of Biostatistics, Fielding School of Public Health at UCLA, Los Angeles, USA. wangyan@ucla.edu.
authors: Yan
authors: Y
authors: Wang
authors: HealthCore, Inc, Wilmington, DE, USA. luthrarakesh1984@gmail.com.
authors: Rakesh
authors: R
authors: Luthra
authors: HealthCore, Inc, Wilmington, DE, USA. Awallace@healthcore.com.
authors: Anna
authors: A
authors: Wallace
authors: HealthCore, Inc, Wilmington, DE, USA. echerry@gmail.com.
authors: Christy
authors: C
authors: Fang
authors: HealthCore, Inc, Wilmington, DE, USA. JSinger@healthcore.com.
authors: Joseph
authors: J
authors: Singer
authors: U.S. Health Outcomes, GlaxoSmithKline, Research Triangle Park, Philadelphia, PA, USA. jose.2.suaya@gsk.com.|U.S. Health Outcomes, NACMA, Vaccines, GlaxoSmithKline, Philadelphia, PA, USA. jose.2.suaya@gsk.com.
authors: Jose A
authors: JA
authors: Suaya
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007297:Inpatients; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D010045:Outpatients; D012189:Retrospective Studies; D018461:Soft Tissue Infections / Q000453:epidemiology* / Q000382:microbiology; D013207:Staphylococcal Skin Infections / Q000453:epidemiology* / Q000382:microbiology; D014481:United States / Q000453:epidemiology; D055815:Young Adult