Risk of venous thromboembolism in Chinese pregnant women: Hong Kong venous thromboembolism study

Abstract

BackgroundPrevious Caucasian studies have described venous thromboembolism in pregnancy; however, little is known about its incidence during pregnancy and early postpartum period in the Chinese population. We investigated the risk of venous thromboembolism in a “real-world” cohort of pregnant Chinese women with no prior history of venous thromboembolism.MethodsIn this observational study, 15,325 pregnancies were identified in 14,162 Chinese women at Queen Mary Hospital, Hong Kong between January 2004 and September 2016. Demographic data, obstetric information, and laboratory and imaging data were retrieved and reviewed.ResultsThe mean age at pregnancy was 32.4±5.3 years, and the median age was 33 years (interquartile range, 29–36 yr). Pre-existing or newly diagnosed diabetes mellitus was present in 627 women (4.1%); 359 (0.7%) women had pre-existing or newly detected hypertension. There was a small number of women with pre-existing heart disease and/or rheumatic conditions. Most deliveries (86.0%) were normal vaginal; the remaining were Cesarean section 2,146 (14.0%). The incidence of venous thromboembolism was 0.4 per 1,000 pregnancies, of which 83.3% were deep vein thrombosis and 16.7% were pulmonary embolism. In contrast to previous studies, 66.7% of venous thrombosis occurred in the first trimester.ConclusionChinese women had a substantially lower risk of venous thromboembolism during pregnancy and the postpartum period compared to that of Caucasians. The occurrence of pregnancy-related venous thromboembolism was largely confined to the early pregnancy period, probably related to the adoption of thromboprophylaxis, a lower rate of Cesarean section, and early mobilization.

Coagulopathy in COVID-19 and Its Implication for Safe and Efficacious Thromboprophylaxis

“…In epidemiological studies, the incidence of VTE was three-to four-fold lower in Chinese compared to Caucasian individuals, while the VTE risk in African Americans appears to be higher than that in Caucasians. [16][17][18] In an Irish cohort of 83 COVID-19 patients, mainly of Caucasian ethnicity, baseline D-dimer levels were significantly increased in patients with a fatal outcome and/or Hyperkoagulabilität, hervorgerufen durch Entzündung und virale Endotheliitis, entwickeln einige Patienten mit fortgeschrittener Erkrankung eine Koagulopathie, die die Laborkriterien einer disseminierten intravasalen Gerinnung erfüllt, jedoch selten mit einer Blutungsneigung einhergeht. Wie andere Fachgesellschaften hat auch die GTH e.V.…”

“…In epidemiological studies, the incidence of VTE was three- to four-fold lower in Chinese compared to Caucasian individuals, while the VTE risk in African Americans appears to be higher than that in Caucasians. 16 17 18 …”

COVID-19 Genetic and Environmental Risk Factors: A Look at the Evidence

“…A hypothesis suggesting the role of coagulation having a major effect in the pathogenesis of COVID-19 was further examined to see differences among different races and ethnicities ( Fogarty et al., 2020 ; Zhou F. et al., 2020 ). Since thrombotic risk differs between races and ethnicities, studies show that African Americans are at higher risk than Caucasians populations ( Huang et al., 2019 ) and the Chinese population has a lower risk of venous thrombo-embolism which is around 3-4 times lower than that in Caucasians ( Liao et al., 2014 ). A study performed in Ireland examining the coagulation in Caucasian patients, the data observed showed a significant relationship between coagulopathy and severity of COVID-19 disease ( Fogarty et al., 2020 ).…”

Anticoagulant Therapy for Patients with Coronavirus Disease 2019: Urgent Need for Enhanced Awareness

“…22 The risk of deep vein thrombosis in Chinese patients is generally one-quarter to one-third of that of white patients, whereas the risk in African-Americans is markedly higher than in white people. 23,24 Therefore, ethnicity needs to be considered when determining anticoagulative strategies for COVID-19 patients. As pulmonary artery thrombosis is frequently observed even in patients undergoing anticoagulation therapy, anticoagulants need to be administered in sufficient amounts.…”