Antibiotic Exposure and Other Risk Factors for Antimicrobial Resistance in Nasal Commensal Staphylococcus aureus: An Ecological Study in 8 European Countries.
OBJECTIVE
Antimicrobial resistance (AMR) has become a global public health concern which threatens the effective treatment of bacterial infections. Resistant Staphylococcus aureus (including MRSA) increasingly appears in individuals with no healthcare associated risks. Our study assessed risk factors for nasal carriage of resistant S. aureus in a multinational, healthy, community-based population, including ecological exposure to antibiotics.


METHODS
Data were collected in eight European countries (Austria, Belgium, Croatia, France, Hungary, the Netherlands, Spain and Sweden). Commensal AMR patterns were assessed by collecting 28,929 nasal swabs from healthy persons (aged 4+). Ecological exposure to antibiotics was operationalized as systemic antibiotic treatment patterns, extracted from electronic medical records of primary care practices in which the participants were listed (10-27 per country). A multilevel analysis related AMR in nasal commensal S. aureus to antibiotic exposure and other risk factors (e.g. age and profession).


RESULTS
Of the 6,093 S. aureus isolates, 77% showed resistance to at least one antibiotic. 7.1% exhibited multidrug resistance (defined as resistance to 3 or more antibiotic classes), and we found 78 cases MRSA (1.3%). A large variation in antibiotic exposure was found between and within countries. Younger age and a higher proportion of penicillin prescriptions in a practice were associated with higher odds for carriage of a resistant S. aureus. Also, we found higher multidrug resistance rates in participants working in healthcare or nurseries.


CONCLUSIONS
This study indicates that in a population with no recent antibiotic use, the prescription behavior of the general practitioner affects the odds for carriage of a resistant S. aureus, highlighting the need for cautious prescribing in primary care. Finally, since variation in AMR could partly be explained on a national level, policy initiatives to decrease AMR should be encouraged at the national level within Europe.
NIVEL, Netherlands Institute for Health Services Research, Utrecht, The Netherlands.
Evelien M E
EM
van Bijnen
NIVEL, Netherlands Institute for Health Services Research, Utrecht, The Netherlands.
John
J
Paget
VU University Medical Centre, Department of Epidemiology and Biostatistics, Amsterdam, The Netherlands.
Elly S M
ES
de Lange-de Klerk
Maastricht University Medical Centre, Department of Medical Microbiology, School for Public Health and Primary Care (CAPHRI), Maastricht, The Netherlands.
Casper D J
CD
den Heijer
University of Antwerp, Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), Antwerp, Belgium.
Ann
A
Versporten
University of Antwerp, Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), Antwerp, Belgium.
Ellen E
EE
Stobberingh
University of Antwerp, Laboratory of Medical Microbiology, Vaccine & Infectious Disease Institute (VAXINFECTIO), Antwerp, Belgium.
Herman
H
Goossens
NIVEL, Netherlands Institute for Health Services Research, Utrecht, The Netherlands; VU University Medical Centre, Department of General Practice and Elderly Care Medicine/EMGO Institute for Health and Care Research, Amsterdam, The Netherlands.
François G
FG
Schellevis
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D002353:Carrier State / Q000382:microbiology*; D002648:Child; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009297:Nasal Mucosa / Q000382:microbiology*; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000187:drug effects*; D055815:Young Adult
D000890:Anti-Infective Agents