1591. Risk Factors Associated with Community-Acquired Pneumonia among Hospitalized Patients: the Impact of Risk Stacking on Long-Term Mortality
Session: Poster Abstract Session: Community Acquired Pneumonia
Saturday, October 10, 2015
Room: Poster Hall
Background: Increasing age and chronic underlying diseases are risk factors for community-acquired pneumonia (CAP). In terms of probability to suffer CAP, some authors have recently published that rates in immunocompetent persons with ≥2 at-risk (AR) conditions (multimorbidity or risk stacking [RS]) were similar or higher than rates in persons with high risk (HR) conditions (immunocompromised). We conducted a hospitalized-based, retrospective cohort study in order to evaluate the long term mortality impact of risk stacking in patients ≥18 years-old with CAP.

Methods: CAP hospitalizations (CAPh) were identified from a large Argentinean health insurance database by searching for CAP codes in discharge diagnoses (International Classification of Diseases-10) in January 1st-December 31st, 2010. A group of controls matched by age was selected (≥ 2 per case). Their hospitalization history was retrieved from that point till 3 years later (up to December 31st, 2014). A conditional logistic regression was used to identify those RF that where associated with new CAP hospitalization (AR [chronic heart disease, chronic lung disease, stroke and diabetes] and HR [HIV, immunosuppressive drugs/conditions and oncohematological disease] conditions).  and mortality.

Results: 219 CAPh and 885 controls were included. Mortality rates were 46% (101/219) and 26% (231/885) in the cases and control groups, respectively (p 0.0000). Both, the presence of AR and HR conditions were identified as significantly associated with an increased mortality (OR 1.40 [95%CI 1.18-1.67] and 2.67 [95%CI 1.49-4.769], respectively), with 2 AR, OR = 1.98 and with 3 AR, OR = 2.78. 68% of deaths in the case group (69/101) and 64% in the control group (150/231) occurred within one year after diagnosis of CAP.

Conclusion: CAP patients ≥18 years-old with AR or HR conditions had an increased mortality rate, mainly after the first year of diagnosis of CAP. These findings demonstrate the high long term impact of the co-occurrence of RF (risk stacking) on the clinical outcomes in adult patients with CAP. Prevention strategies for CAP such us pneumococcal and influenza vaccination recommendations, should consider the risk stacking impact beyond the defined risk conditions (AR and HR).

Francisco Fernandez, MD1, Alejandro Cane, MD2, Raul Isturiz, MD3, Daniel Curcio, MD2 and Mauricio Peralta, MD1, (1)Medical, AudiRED SRL, Buenos Aires, Argentina, (2)Pfizer Argentina, Buenos Aires, Argentina, (3)Pfizer Inc., New York, NY


F. Fernandez, None

A. Cane, None

R. Isturiz, None

D. Curcio, None

M. Peralta, None

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