Objective: to determine the incidence of deep vein thrombosis (DVT) in the general population by pooling results from all studies of adequate quality.
Design: systematic review including meta-analysis.
Material and methods: MEDLINE (1966-2001) and EMBASE (1950-2001) were searched for studies on the incidence of DVTand thromboembolism in the general population. Studies had to attain minimum inclusion and quality criteria to be accepted for the review, including adequate specification of the diagnosis of DVT and the age range of the population. The appraisal of studies for inclusion and abstraction of data were carried out independently by each author. Incidence rates were adjusted to standardise for differences between studies in categories of DVT and population age structures. Weighted and unweighted means of incidence per 10 000 person years were estimated.
Results: nine studies were identified which fulfilled the inclusion and quality criteria. Most were conducted in Sweden or U.S.A. between 1976 and 2000. The weighted mean incidence of first DVT in the whole general population was 5.04 (95% CI 4.70, 5.38) per 10 000 person years. The incidence was similar in males and females and increased dramatically with age from about 2-3 per 10 000 person years at age 30-49 to 20 per 10 000 person years at age 70-79. Around 40% of cases of DVT were idiopathic.
Conclusion: this study provides the most comprehensive estimate to date of the incidence of DVT in the whole general population-around 5 per 10 000 per annum-and is a useful background figure for comparison with incidence in high risk groups.