Mortality Differences among Hospitalized Patients with Severe Community-acquired Pneumonia in Three World Regions: Results from the Community-Acquired Pneumonia Organization (CAPO) International Cohort Study.

Joannis Baez MD1, Emily Pacholski MPHc1, Murali Kolikonda MD1, Lisandra Rodriguez MD1, Francisco Fernandez MD1, Robert Kelley PhD1, Timothy Wiemken PhD, MPH1; Paula Peyrani MD1, Julio Ramirez MD1, Rodrigo Cavallazzi MD2

1. Division of Infectious Diseases, University of Louisville, Louisville, KY; 2. Pulmonary and Critical care

MATERIALS AND METHODS (Cont’d)

REFERENCES

INTRODUCTION

Definitions: Community-Acquired Pneumonia: Evidence of a new pulmonary infiltrate at chest radiograph associated with at least one of the following: new or increased cough, fever or hypothermia, leukocytosis, left shift, or leukopenia.

Severe Community-Acquired Pneumonia: Patients with community-acquired pneumonia that require intensive care unit admission. Pneumonia Severity Index was used to compare acuity of SCAP.

Length of Hospital Stay was calculated as the number of days between admission and discharge from the hospital.

Time to Reach Clinical Stability was defined on the day the patient met the following four criteria: 1) Adequate oral intake, 2) improvement in white blood cell count, 3) Afebrile for 8 hours, 4) Improvement in signs and symptoms (cough and shortness of breath).

Study regions were defined as US/Canada (Region I), Europe (Region II), and Latin America (Region III), as depicted in Figure 1.

Descriptive analyses were performed to characterize the patient population in each region.  

CONCLUSIONS

There was a difference on in-hospital mortality in patients with Severe Community-Acquired Pneumonia (SCAP) between the three different world regions with Latin America being the highest.

The Pneumonia Severity Index was higher in Latin America compared with US/Canada and Europe.

Europe and Latin America were the two regions in which time to clinical stability and length of stay were higher.

Streptococcus pneumoniae and Haemophilus influenzae were the two most frequent microorganisms isolated, both with predominant levels in Latin America.

Differences in mortality of SCAP patients in different regions can be due to:

1.Host characteristics2.Pathogen specific virulence factors 3.Quality of care

1. Murray CJ, Lopez AD. Mortality by cause for eight regions of the world:Global Burden of Disease Study. Lancet 1997;349:1269e76.2. World Health Organization. Health statistics and health information systems. http://www.who.int/healthinfo/global burden disease/estimates_regional/en/index.html; 2008 [accessed March 20].3. Minino A, Heron M, Smith B, Minino AM, Heron MP, Smith BL. Deaths: preliminary data for 2004. Natl Vital Stat Rep 2006;54:19. Available from: http://www.cdc.gov/nhc/data/nvsr/nvsr54/nvsr54_19.pdfS.4. File Jr TM, Marrie TJ. Burden of community-acquired pneumonia in North American adults. Postgrad Med 2010;122: 130e41.5. Arnold FW, Ramirez JA, McDonald LC, et al. Hospitalization for community-acquired pneumonia: the pneumonia severity index vs clinical judgment. Chest 2003;124:121e4.6 Fine MJ. Risk stratification for patients with communityacquired pneumonia. Int J Clin Pract Suppl 2000:14e7. 

Studies rarely compare outcome measures between world regions. In order to determine a difference in mortality between regions of the world, a single study is needed which examines multiple regions. It is important to discover if a difference in mortality exists, and to identify any modifiable causes that would decrease mortality rates of patients with SCAP. The objective of this study is to analyze differences in mortality among hospitalized patients with SCAP in three different world regions: Europe, Latin America and US/Canada. 

Table 1 Demographics of 635 patients with severe community-acquired pneumonia in three regions of the world. The numbers of patients are listed with the corresponding proportion in parentheses.

Region I Region II Region III

US/Canada Europe Latin America

n =244 n = 115 n=276

Male 174 (71) 83 (72) 1 3 9 (50) Mean age 61 ± 27 63 ± 27 6 4 ± 33 COPD 83 (34) 30 (20) 68 (25) Diabetes mellitus 62 (25) 2 3 (20) 30 (11) Cerebrovascular disease 22 (9) 13 (11) 26 (9) Congestive heart failure 63 (26) 18 (16) 72 (26) Liver disease 19 (7.8) 18 (16) 6 (2.2) Renal disease 34 (14) 16 (14) 21 (8) Neoplastic disease 32 (13) 5 (4) 16 (6)

COPD = chronic obstructive pulmonary disease

Figure:4 Length of stay and time to clinical stability of patients with severe community-acquired pneumonia in three different regions of the world.

Figure:2 In-Hospital mortality due to Severe Community-Acquired Pneumonia in three different regions of the world.

RESULTS (Cont’d)

Despite the advancement in the management of community-acquired pneumonia (CAP), it still has considerable worldwide morbidity and mortality. The World Health Organization has reported for decades that lower respiratory tract infections are the third leading cause of death globally1,2 In the US it is the number one cause of death due to infectious disease with a mortality rate of 20.9/100,000. In Canada the rate is 12.7/100,0003,4 In Europe, the reported mortality varies broadly6.Severe community-acquired pneumonia (SCAP) can be defined as CAP that requires intensive care unit (ICU) admission. SCAP is associated with high morbidity, mortality, and increased health-care costs. There are limited data comparing clinical outcomes in patients with SCAP among different world regions. Independent studies evaluate mortality rates for hospitalized patients with SCAP in individual countries, mostly in the US and Europe.  

Figure 3: Pneumonia Severity Index (PSI) in Severe Community- Acquired Pneumonia patients in three different regions of the world

US/Canada Europe Latin America98

100

102

104

106

108

110

112

114

116

118

Pneumonia Severity Index (Median)

Pneumonia Severity Index (Median)

US/Canada Europe Latin America0

2

4

6

8

10

12

14

16

Mean Length of stay (days)Mean Time to clinical stability (days)

RESULTS

RESULTS (Cont’d)

Figure 5: Etiology of Severe Community-Acquired Pneumonia in three different regions of the world.

MATERIALS AND METHODS

Study Design

• This was a secondary data analysis of hospitalized patients with Severe Community-Acquired Pneumonia from the Community-Acquired Pneumonia Organization (CAPO) international cohort study.

• Data were gathered between November 2001 and June 2013 and include patients 18 years of age or older with Severe Community-Acquired Pneumonia.

• A total of 70 institutions in 16 countries in Europe, Latin America and US/Canada were included.

• CAPO has been described previously.4 • The case report form as well as other details of CAPO may be

reviewed at www.caposite.com.

Baseline patient characteristics can be found in Table 1.

Figure 2 depicts the overall rate of in-hospital-mortality in each region.

Figure 3 depicts the pneumonia severity index in each region.

Time to clinical stability and Length of stay between three different regions of the world were compared as depicted in Figure 4.

The etiology of severe community-acquired pneumonia was taken from the reference microbiology laboratory (Figure 5).

Figure 1: CAPO regions

US/Canada Europe Latin America0%

5%

10%

15%

20%

25%

30%

Microorganisms Chlamydia PneumoniaeMicroorganisms Haemophilus InfluenzaeMicroorganisms Streptococcus PneumonaieMicroorganisms Moraxella Catarrhalis