[Ability of the modified CRB75 severity scale in assessing elderly patients with community acquired pneumonia]

Objetivo

Comparar la utilidad de la escala CRB65, acrónimo inglés de confusión, taquipnea, hipotensión, edad ≥ 65 años, versus la escala modificada CRB75 para determinar el grado de severidad en pacientes mayores de 65 años con neumonía adquirida en la comunidad (NAC).

Diseño

Estudio de cohortes prospectivo.

Emplazamiento

Región Sanitaria de Tarragona.

Participantes

Se incluyeron 350 pacientes ≥ 65 años con NAC radiográficamente confirmada (ambulatoria u hospitalizada) diagnosticada durante 2008-2010.

Mediciones principales

La escala CRB65 considera confusión mental de nueva aparición; frecuencia respiratoria ≥ 30 resp./min; presión arterial sistólica < 90 mmHg o diastólica ≤ 60 mmHg y edad ≥ 65 años. La escala modificada CRB75 usa criterios similares pero edad ≥ 75 años. Ambas fueron calculadas al diagnóstico, y la mortalidad a los 30 días fue considerada como variable dependiente.

Resultados

La mortalidad global fue del 13,1% (4% en NAC ambulatorias y 15% en NAC hospitalizadas). La mortalidad fue 7,7% para CRB65 = 1, 22,5% en CRB65 = 2 y 50% en CRB65 = 3. La mortalidad en CRB75 = 0 fue 3,2%, en CRB75 = 1 fue 9,7%, en CRB75 = 2 fue 30% y en CRB75 = 3 del 45,5%. La capacidad discriminativa de ambas escalas para clasificar el riesgo de mortalidad a los 30 días fue aceptable, siendo el área bajo la curva ROC significativamente mejor en el CRB75 que en el CRB65 (0,735 vs 0,681; p < 0,01).

Conclusión

Ambas escalas son una herramienta aceptable para clasificar el riesgo de mortalidad a corto plazo en los pacientes con NAC. La escala CRB75 puede ser de mayor utilidad en pacientes mayores de 65 años.

Comparison of three predictive rules for assessing severity in elderly patients with CAP

AIM

This study compares the ability of the Pneumonia Severity Index (PSI) and the British Thoracic Society CURB-65 and CRB-65 rules in predicting short-term mortality among elderly patients with community-acquired pneumonia (CAP).

METHODS

It is a population-based study including all people over 65 years old with a radiographically confirmed CAP in the region of Tarragona (Spain) between 2002 and 2008. Treatment setting and clinical variables were considered for each patient. PSI, CURB-65 and CRB-65 scores were calculated at the moment of diagnosis and 30-day mortality was considered as a main dependent variable. The rules were compared based on sensitivity, specificity and area under the receiver operating characteristic curve (AUC).

RESULTS

Of the total 590 CAP cases, mortality rate was 13.6% (15.3% in hospitalised and 1.4% in outpatient cases; p = 0.001). Mortality increased with increasing PSI score (None in class II, 6,9% in class III, 14,4% in class IV and 29,5% in class V), CURB-65 score (7.5%, 14.5%, 26.7%, 53.3% and 100% for scores 1,2,3,4 and 5 respectively) and CRB-65 score (6.6%, 26.1%, 40.5% and 50% for scores 1,2,3 and 4 respectively). The three rules performed too similarly to predict 30-day mortality, with a ROC area of 0.727 [95% confidence interval (CI): 0.67-0.79] for the PSI, 0.672 (95% CI: 0.61-0.74) for the CURB-65, and 0.719 (95% CI: 0.65-0.78) for the CRB-65.

CONCLUSION

Our data shows that the analysed rules perform equally well among elderly people with CAP which supports the recommendation for using the simplified CRB-65 severity score among elderly patients in primary care or emergency visits.

[Usefulness of the CRB-65 scale for prognosis assessment of patients 65 years or older with community-acquired pneumonia]

BACKGROUND AND OBJECTIVE

The assessment of severity may be important to decide hospitalisation and type of treatment in community-acquired pneumonia (CAP) cases. This study evaluated the ability of the severity rule CRB-65 for the management of older adults with CAP.

PATIENTS AND METHODS

Population-based study including 473 patients 65 years or older with a radiographically confirmed CAP in the region of Tarragona (Spain). Treatment setting and clinical variables were considered for each patient, CRB-65 score (confusion, respiratory rate>or=30, systolic blood pressure<90 mmHg or diastolic<or=60 mmHg, age>or=65 years) was calculated at the time of diagnosis, and 30-day mortality was considered as a main dependent variable.

RESULTS

Overall mortality rate was 12.7% (15.5% among hospitalised and 1.7% in outpatient cases). Mortality was directly associated with the CRB-65 score, being 6.8% in score 1 (2.4% among patients 65-74 years and 10.1% in patients 75 years or older; P=.005), 26.1% in score 2, 41.7% in score 3 and 66.7% in score 4. For a breakpoint of CRB-65 score>or=2, sensitivity was 60% (95% CI: 42-78) and specificity was 80% (95% CI: 76-84).

CONCLUSIONS

The CRB-65 has an acceptable ability to classify mortality risk in elderly patients with CAP. Patients with CRB-65=1 have a relatively small mortality rate, which suggests that they could be managed as outpatients.