Validation of the Swedish National Inpatient Register for the diagnosis of pulmonary embolism in 2005

Abstract

Abstract The Swedish National Inpatient Register (NPR) has near‐complete coverage of in‐hospital admissions and ICD codes in Sweden. Acute pulmonary embolism (PE) is a serious condition presenting challenges regarding diagnosis, treatment, and follow‐up. Here we aimed to validate the accuracy of acute PE diagnosis in the NPR, investigational findings, antithrombotic treatment, and follow‐up of PE patients in Sweden. From a nation‐wide cohort of all patients with in‐hospital diagnoses of acute PE (ICD‐10‐SE codes I26.0–I26.9) in 2005 (n = 5793), we selected those from two Swedish regions for thorough manual review of hospital records. We identified 599 patients with PE diagnoses according to the ICD‐10 coding system. We excluded 58 patients with admissions related to previous PE (47; 8%) or incorrect ICD codes (11; 2%), leaving 501 patients with probable PE diagnoses. We confirmed the diagnosis in 441 (79%) cases, which was based on imaging (435 patients; 73%) or autopsy (6; 1%). In the remaining 60 (11%) cases, the PE diagnosis was based on clinical findings and can therefore not be confirmed. Of the surviving patients with PE, 231 (47%) were offered follow‐up within 6 months after the acute event. At follow‐up, 67 patients (29%) had symptoms requiring clinical attention (dyspnoea or reduced general condition). The Swedish NPR showed acceptable accuracy for PE diagnosis, and could be reliably used for register‐based research regarding acute PE.

Keywords

• clinical presentation
• epidemiology
• follow‐up
• pulmonary embolism
• register