Predicting Death in Elderly Patients With Community-Acquired Pneumonia: A Prospective Validation Study Reevaluating the CRB-65 Severity Assessment Tool

Abstract

S everity scores are helpful in predicting mortality in patients presenting with communityacquired pneumonia (CAP). They enable physicians to decide their management strategies and site of care according to the expected mortality risk. In Europe, most cases of lower respiratory tract infections (LRTIs) and CAP are managed in primary care settings by general practitioners (GPs). However, most severity scores have been derived and validated in a hospital setting. The best accepted tools to discriminate patients with CAP into high or low risk are the CURB-65 score (confusion, serum urea nitrogen level Ͼ19.6 mg/dL [to convert to millimoles per liter, multiply by 0.357], respiratory rate Ն30/min, low blood pressure, and age Ն65 years) and the Pneumonia Severity Index (PSI). 1,2 The CURB-65 score consists of 5 easily accessible data, while the PSI includes many tests that are not accessible in primary care. This latter score is therefore not useful for the GP. Recently, several studies evaluated the CURB-65 score and confirmed its validity, but validation was not yet done in an unselected primary care population. 3-9 A modification of the CURB-65 score, the CRB-65 score, is recommended by GPs in the communities where serum urea nitrogen measurements are often unavailable. It is expected to support GP judgment in stratifying patients into different management groups, ranging from home treatment to urgent hospital admission (Figure). 1 This management model seems unlikely to be practical in a primary care population because it recommends hospital referral for a score of 1 or higher and thus for all patients older than 65 years (Figure). We therefore conducted a study to evaluate the validity of the CRB-65 score in primary care. Methods. Study Population. Between November 2005 and May 2006, Dutch GPs prospectively included patients with CAP who were 65 years or older. Community-acquired pneumonia was diagnosed on the basis of the presence of 1 or more features, including new localizing signs present during chest examination, new infiltrates on a

Validity of British Thoracic Society guidance (the CRB-65 rule) for predicting the severity of pneumonia in general practice: systematic review and meta-analysis

“…In order to calculate the predicted score, the proportionate mortality estimate from the original derivation study was applied according to the three risk strata -low risk (mortality = 1.2%), intermediate risk (mortality = 8.2%), and high risk (mortality = 31.3%), 3 an approach previously used in a community-based validation study. 8 The predicted:observed risk ratios for these three risk strata are presented separately for patients who were treated in the community or in hospital. Results are presented as risk ratios (RRs) with 95% confidence intervals (CIs).…”

“…8,[11][12][13][14][15][16][17][18][19][20][21][22][23] Table 1 summarises the characteristics of the included studies. Additional data were provided from three studies, 13,15,23 and clarification of included overlapping subjects obtained from two other studies.…”

“…Additional data were provided from three studies, 13,15,23 and clarification of included overlapping subjects obtained from two other studies. 12,16 Only one study was performed entirely in a primary care setting, 8 although two other studies did include data from patients who were treated as outpatients. 12,14 The included studies ranged in size from 105 patients to 388 406 patients, with a broadly equal sex balance.…”

“…[5][6][7] The CRB-65 rule has been validated extensively in separate studies, although for a clinical prediction rule specifically intended for community use there have been few validation studies performed wholly in primary care. 1,8 As clinical prediction rules may not perform well in practice because of deficiencies in the development methods or because of differences between the original sample and the validation sample, it is good practice to assess their validity across a broad range of eligible patient groups. 9 The aim of this study was to perform a comprehensive systematic review and meta-analysis of validation studies of CRB-65, to determine its accuracy in predicting 30-day mortality and assess how well it performs in community and hospital settings.…”

The International Primary Care Respiratory Group (IPCRG) Research Needs Statement 2010

“…285 Clinical prediction rules to determine high and low risk elderly patients show promise in assisting primary care clinicians to decide who may be managed at home and who need closer monitoring or hospital care. 286,287 Morbidity and mortality from respiratory infections are greater in patients with co-morbidities such as COPD, asthma, diabetes, renal failure, alcohol abuse, and immunosuppression. 288,289 Smokers are prescribed antibiotics more frequently than non-smokers, with no apparent benefit.…”