title: Long-term mortality and incidence of cancer after pregnancy-related venous thrombosis: results of a population-based cohort study.
abstract: The long-term mortality and incidence of cancer after pregnancy-related venous thrombosis (VT) is not known. In this population-based cohort study we identified women with a first-ever pregnancy-related VT (cases, n = 557)) from 18 Norwegian hospitals during 1990-2003. Hospital controls (n = 1214) were selected among women who gave birth at the same time as a case. All participants were linked to the Norwegian Cause of Death Registry and to the Cancer Registry of Norway in 2012. The general age-adjusted Norwegian female population was used as a second control group to calculate the standardized mortality ratio (SMR) and the standardized incidence ratio (SIR) for cancer. Ten cases (1.8%) and seven hospital controls (0.6%) died during follow-up. Mortality was 3.2 times higher among cases as compared with hospital controls when adjusted for age (HR 3.2, 95% confidence interval 1.2-8.5, p = 0.018). The SMR for the first year of follow-up was 18.8 (7.8-45.3) and for the rest of the study period 0.9 (0.4-2.0). Fifteen cases (2.7%) and 13 hospital controls (1.1%) were diagnosed with cancer after index pregnancy. The incidence of cancer was 2.6 times higher among cases compared with hospital controls when adjusted for age (HR 2.6, 1.3-5.6, p = 0.011), but compared with the age-adjusted female population in Norway there was no excess risk of cancer (SIR 1.0, 95% CI 0.6-1.7). Mortality and incidence of cancer after pregnancy-related VT was low. Both were increased among cases compared with hospital controls, but not when compared with the general population, except for mortality during the first year after VT.
authors.affiliation: Department of Haematology, Oslo University Hospital, Oslo, Norway.
authors.forename: Hilde S
authors.initials: HS
authors.lastname: Wik
authors.forename: Anne F
authors.initials: AF
authors.lastname: Jacobsen
authors.forename: Morten W
authors.initials: MW
authors.lastname: Fagerland
authors.forename: Leiv
authors.initials: L
authors.lastname: Sandvik
authors.forename: Per Morten
authors.initials: PM
authors.lastname: Sandset
mesh_terms: D000328:Adult; D000367:Age Factors; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000453:epidemiology*; D011252:Pregnancy Complications, Neoplastic / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality*; D020246:Venous Thrombosis / Q000150:complications* / Q000453:epidemiology*