Dental and microbiological risk factors for hospital-acquired pneumonia in non-ventilated older patients.
METHODS
We obtained a time series of tongue/throat swabs from 90 patients with lower limb fracture, aged 65-101 in a general hospital in the North East of England between April 2009-July 2010. We used novel real-time multiplex PCR assays to detect S. aureus, MRSA, E. coli, P. aeruginosa, S. pneumoniae, H. influenza and Acinetobacter spp. We collected data on dental/denture plaque (modified Quigley-Hein index) and outcomes of clinician-diagnosed HAP.


RESULTS
The crude incidence of HAP was 10% (n = 90), with mortality of 80% at 90 days post discharge. 50% of cases occurred within the first 25 days. HAP was not associated with being dentate, tooth number, or heavy dental/denture plaque. HAP was associated with prior oral carriage with E. coli/S. aureus/P.aeruginosa/MRSA (p = 0.002, OR 9.48 95% CI 2.28-38.78). The incidence of HAP in those with carriage was 35% (4% without), with relative risk 6.44 (95% CI 2.04-20.34, p = 0.002). HAP was associated with increased length of stay (Fishers exact test, p=0.01), with mean 30 excess days (range -11.5-115). Target organisms were first detected within 72 hours of admission in 90% participants, but HAP was significantly associated with S. aureus/MRSA/P. aeruginosa/E. coli being detected at days 5 (OR 4.39, 95%CI1.73-11.16) or 14 (OR 6.69, 95%CI 2.40-18.60).


CONCLUSIONS
Patients with lower limb fracture who were colonised orally with E. coli/ S. aureus/MRSA/P. aeruginosa after 5 days in hospital were at significantly greater risk of HAP (p = 0.002).
Newcastle University Institute for Ageing, Newcastle upon Tyne, United Kingdom.
Victoria C
VC
Ewan
Public Health England, Microbiology Services, Newcastle Laboratory, Newcastle upon Tyne, United Kingdom.
Andrew D
AD
Sails
Edinburgh Dental Institute, University of Edinburgh, Edinburgh, United States of America.
Angus W G
AW
Walls
Biological Modelling, Newcastle University, Newcastle upon Tyne, United Kingdom.
Steven
S
Rushton
Newcastle University Institute for Ageing, Newcastle upon Tyne, United Kingdom.
Julia L
JL
Newton
D000150:Acinetobacter / Q000235:genetics / Q000302:isolation & purification; D000368:Aged; D000369:Aged, 80 and over; D003428:Cross Infection / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology*; D003773:Dental Plaque / Q000150:complications* / Q000453:epidemiology; D004739:England / Q000453:epidemiology; D004926:Escherichia coli / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D050723:Fractures, Bone / Q000150:complications* / Q000453:epidemiology; D006193:Haemophilus influenzae / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D007902:Length of Stay; D008297:Male; D009055:Mouth / Q000382:microbiology; D018410:Pneumonia, Bacterial / Q000150:complications / Q000453:epidemiology* / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000302:isolation & purification; D012307:Risk Factors; D013211:Staphylococcus aureus / Q000235:genetics / Q000302:isolation & purification