Summary

The incidence of venous thromboembolism has been studied duringone year in a defined population of 342,000 inhabitants. The overallincidence (95% confidence interval) of venous thromboembolism wasfound to be 1.83 per thousand per year (1.69 to 1.98). The incidencesof deep venous thrombosis and pulmonary embolism were 1.24 perthousand per year (1.12 to 1.36) and 0.60 per thousand per year (0.52 to0.69), respectively. The incidence of venous thromboembolism rosemarkedly with increasing age for both sexes; over the age of 75, theannual incidence reached 1 per 100. Sixty three percent of the patientswere at home when venous thromboembolism occurred. Of these,sixteen percent had been previously hospitalised within three months.These results raise concerns on identification of medical patients athigh risk and effective prophylaxis.