Differential value of risk factors and clinical signs for diagnosing pulmonary embolism according to age

INTRODUCTION: The diagnostic value of clinical presentation of pulmonary embolism (PE) is uncertain in the elderly, who often have concomitant cardiopulmonary diseases that may mimic PE. The aim of our study was to assess the differential value of risk factors, symptoms and clinical signs of venous thromboembolism, results of electrocardiogram and chest X-ray for the diagnosis of PE in suspected patients according to age. METHODS: We analyzed data from two outcome studies which enrolled 1721 consecutive patients presenting in the emergency department with clinically suspected PE defined as acute onset of new or worsening shortness of breath or chest pain without any other obvious etiology. All patients underwent a sequential diagnostic work-up and a 3-month follow-up. RESULTS: The proportion of confirmed PE was 24.2% (416 of 1721). Strength of the association with PE did not differ according to age group for history of venous thromboembolism (VTE), recent surgery, tachypnea at admission or right ventricular strain on electrocardiogram. Active malignancy, hemoptysis, tachycardia, hemidiaphragmatic elevation and pleural effusion at chest X-ray were no more associated with PE in the patients aged of 75 years or more. Finally, symptoms and signs of deep venous thrombosis, and an alternative diagnosis less probable than PE were associated with PE in all age groups, but the strength of this association decreased significantly with advancing age. CONCLUSION: Some risk factors, symptoms and signs of VTE are less strongly or even not at all associated with PE in the elderly. Physicians should take this into account when attending elderly patients suspected of PE and when assessing their clinical probability of PE.