878. Modifiable Risk Factors for Pneumonia Requiring Hospitalization among Community-Dwelling Older Adults: The Health, Aging, and Body Composition (Health ABC) Study
Session: Oral Abstract Session: Microbiome and Susceptibility to Infection
Saturday, October 22, 2011: 10:45 AM
Room: 156ABC
Background:  Pneumonia is a leading cause of death among older adults (age ≥ 65).  The primary aim of this study was to identify modifiable risk factors (MRF) for pneumonia in community-dwelling older adults amenable to innovative prevention strategies.

Methods:  The Health ABC study is a prospective cohort of 3075 community dwelling adults age 70-79 enrolled from 1997-98.  Of 3075 subjects, 1975 had a dental exam in 1998-99, 1656 had a mean oral plaque score, and 1575 had risk factors assessed within 6 months of dental exam.  To examine risk of poor oral hygiene and other potential MRF, we analyzed these 1575 subjects for incident pneumonia.  Risk factors were age, gender, race, comorbidities, medications, vaccination status, history of pneumonia, mean oral plaque score (range 0-3), other measures of oral health, BMI, active smoking, and development of physical impairment.  The primary outcome was pneumonia requiring hospitalization.  The diagnosis of pneumonia required compatible clinical features and/or a new or progressive chest X-ray abnormality compatible with pneumonia.  Bivariate and multivariable associations between risk factors and time to pneumonia were made using Cox regression models.  Average Attributable Fractions (AAF) were calculated to estimate the contribution of each risk factor for pneumonia.

Results:  Of 1575 subjects, 218 developed pneumonia requiring hospitalization through 2008.  In the multivariable model, male gender (HR 2.22, 1.67-2.95), white race (HR 1.50, 95% CI 1.09-2.05), development of physical impairment (HR 2.13, 1.62-2.81), H2 blocker use (HR 1.46, 1.08-2.00) and higher mean oral plaque score (HR 1.45, 1.17-1.80) were risk factors for pneumonia.  Higher BMI (HR 0.92, 0.89-0.95) and statin use (HR 0.64, 0.48-0.85) were protective.  The AAF were as follows:  23% male gender, 15% white race, 15% development of physical impairment, 15% mean oral plaque score ≥ 1, 14% BMI<25, and 4% H2 blocker use.  All risk factors were validated using bootstrapping.

Conclusion:  High oral plaque score, development of physical impairment, and low BMI are the MRF with the highest attributable risk for pneumonia requiring hospitalization. These data suggest novel innovative opportunities for pneumonia prevention in community-dwelling older adults.

Subject Category: C. Clinical studies of bacterial infections and antibacterials including sexually transmitted diseases and mycobacterial infections (surveys, epidemiology, and clinical trials)

Manisha Juthani-Mehta, MD1, Nathalie de Rekeneire, MD2, Heather Allore, PhD2, Shu Chen, MS2, John O'Leary, MA2, Douglas Bauer, MD3, Tamara Harris, MD4, Anne Newman, MD5, Sachin Yende, MD5, Robert Weyant, DMD5, Stephen Kritchevsky, PhD6 and Vincent Quagliarello, MD1, (1)Internal Medicine, Infectious Diseases, Yale School of Medicine, New Haven, CT, (2)Yale School of Medicine, New Haven, CT, (3)University of California, San Francisco, San Francisco, CA, (4)National Institute on Aging, Bethesda, MD, (5)University of Pittsburgh, Pittsburgh, PA, (6)Wake Forest School of Medicine, Winston Salem, NC


M. Juthani-Mehta, None

N. de Rekeneire, None

H. Allore, None

S. Chen, None

J. O'Leary, None

D. Bauer, None

T. Harris, None

A. Newman, None

S. Yende, None

R. Weyant, None

S. Kritchevsky, None

V. Quagliarello, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.