• bipolar disorder;
  • pulmonary embolism

Objectives:  The purpose of this study was to investigate the increased risk for pulmonary embolism (PE) in patients with manic-depressive psychosis/bipolar disorder (BD). Affective patients show increased mortality compared with the background population.

Methods:  A register study was carried out in which somatic and psychiatric information in 25,834 BD patients and 117,815 controls was extracted from The Danish Psychiatric Central Research Register, The National Register of Patients, The Danish Central Person Register and The Danish Register of Causes of Death, with similar information about patients with schizophrenia and anxiety for comparison.

Results:  Patients with BD had a significantly increased occurrence of PE [increased incidence rate ratio (IRR) = 1.61; 95% confidence interval (CI) (1.38, 1.88)]. An association was also found in schizophrenic patients [IRR = 1.78; 95% CI (1.27, 2.51)] and in anxiety patients [IRR = 1.49; 95% CI (1.10, 2.02)].

Conclusions:  Increased occurrence of PE in patients with BD is one of the explanations of increased mortality in the affective patient group. A similar finding in females with schizophrenia and females with anxiety suggests ‘mental disorder’ as the risk factor for PE. The causes for the increased occurrence of PE in BD patients (and other diagnostic groups) need further investigation.