title: Deep vein thrombosis and pulmonary embolism in two cohorts: the longitudinal investigation of thromboembolism etiology.
abstract: OBJECTIVE
  To determine the incidence of deep vein thrombosis and pulmonary embolism in two cohorts representing regions of the United States.
  
  
  METHODS
  The sample comprised 21,680 participants of the Atherosclerosis Risk in Communities study and the Cardiovascular Health Study. Subjects were aged >/=45 years, resided in six communities, and were followed for 7.6 years. All hospitalizations were identified and thromboses were validated by chart review.
  
  
  RESULTS
  The age-standardized incidence of first-time venous thromboembolism was 1.92 per 1000 person-years. Rates were higher in men than women, and increased with age in both sexes. There was no antecedent trauma, surgery, immobilization, or diagnosis of cancer for 48% (175/366) of events. The 28-day case-fatality rate was 11% (29/265) after a first venous thromboembolism and 25% (17/67) for cancer-associated thrombosis. The recurrence rate 2 years after a first venous thromboembolism was 7.7% per year (95% confidence interval [CI]: 4.5% to 10.9% per year). Cancer was the only factor independently associated with 28-day fatality (relative risk [RR] = 5.2; 95% CI: 1.4 to 19.9) or recurrent thrombosis (RR = 9.2; 95% CI: 2.0 to 41.7).
  
  
  CONCLUSIONS
  The incidence of venous thromboembolism in this cohort of middle- and older-aged subjects was similar to that observed in more geographically homogeneous samples. Half of cases were idiopathic. Short-term mortality and 2-year recurrence rates were appreciable, especially among subjects with cancer. Based on this study we estimate that 187,000 cases of first-time venous thromboembolism are diagnosed yearly in the United States among those aged 45 years or older.
authors.affiliation: Department of Medicine, University of Vermont, Burlington, USA. mary.cushman@uvm.edu
authors.forename: Mary
authors.initials: M
authors.lastname: Cushman
authors.forename: Albert W
authors.initials: AW
authors.lastname: Tsai
authors.forename: Richard H
authors.initials: RH
authors.lastname: White
authors.forename: Susan R
authors.initials: SR
authors.lastname: Heckbert
authors.forename: Wayne D
authors.initials: WD
authors.lastname: Rosamond
authors.forename: Paul
authors.initials: P
authors.lastname: Enright
authors.forename: Aaron R
authors.initials: AR
authors.lastname: Folsom
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications / Q000453:epidemiology; D011159:Population Surveillance; D011655:Pulmonary Embolism / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality; D012008:Recurrence; D012307:Risk Factors; D015996:Survival Rate; D020246:Venous Thrombosis / Q000453:epidemiology* / Q000209:etiology