Hematocrit and risk of venous thromboembolism in a general population. The Tromso study

Abstract

BackgroundHematocrit above the normal range for the population, such as in primary or secondary erythrocytosis, predisposes to both arterial and venous thrombosis. However, little is known about the association between hematocrit and risk of venous thromboembolism in a general population. Design and MethodsHematocrit and related hematologic variables such as hemoglobin, red blood cell count, mean corpuscular volume, and baseline characteristics were measured in 26,108 subjects, who participated in the Tromsø Study in 1994-1995. Incident venous thromboembolic events during follow-up were registered up to September 1 st , 2007. ResultsThere were 447 venous thromboembolic events during a median of 12.5 years of followup. Multivariable hazard ratios per 5% increment of hematocrit for the total population, adjusted for age, body mass index and smoking, were 1.25 (95% CI: 1.08-1.44) for total venous thromboembolism and 1.37 (95% CI: 1.10-1.71) for unprovoked venous thromboembolism. In category-based analyses, men with a hematocrit in the upper 20 th percentile (≥46% in men) had a 1.5-fold increased risk of total venous thromboembolism (95% CI: 1.08-2.21) and a 2.4-fold increased risk of unprovoked venous thromboembolism (95% CI: 1.36-4.15) compared to men whose hematocrit was in the lower 40 th percentile. The risk estimates were higher for men than for women both in continuous and category-based analyses. The findings for hemoglobin and red blood cell count were similar to those for hematocrit, whereas mean corpuscular volume was not associated with venous thromboembolism. ConclusionsOur findings suggest that hematocrit and related hematologic variables such as hemoglobin and red blood cell count are risk factors for venous thromboembolism in a general population.Key words: hematocrit, population range, arterial and venous thrombosis. Study. Haematologica. 2010; 95:270-275. doi:10.3324/haematol.2009 Hematocrit and risk of venous thromboembolism in a general population. The Tromsø study Citation: Braekkan SK, Mathiesen EB, Njølstad I, Wilsgaard T, and Hansen J-B. Hematocrit and risk of venous thromboembolism in a general population. The Tromsø

Dynamics of hevostatic parameters on pregnant women and after delivery

“…В работе использовали следующую панель со-временного оборудования, применяющуюся в оте чес твенных клинико-диагностических лабора-ториях*: гематологический анализатор MEK-7222 J/K [1] («Nihon Kohden»); агрегометры оптические -Chronolog 490-4D [2] («CHRONO-LOG Corporation») и AggRAM [3] («Helena Laboratories»); коагулометры полуавтоматические -Helena C-1 [4] , АПГ4-02П [5] («ЭМКО») и Start 4 [6] («Stago»); автоматические ко-агулометры -STA Compact [7] («Stago») и Sysmex CA-1500 [8] («Sysmex Corporation»); планшетный флюориметр Fluoroskan Ascent [9] («ThermoFisher SCIENTIFIC») с программным обеспечением Thrombinoscope 3.0.0.26; тромбоэластометр 4-ка-нальный ROTEM Gamma [10] («Rotem»); иммуно-химические анализаторы -IMMULITE 2000 [11] («Siemens Healthcare Diagnostics») и Architect i2000 [12] ОРИГИНАЛЬНЫЕ И ОБЗОРНЫЕ СТАТЬИ («ABBOTT LABORATORIES S.A.»); фотометры -спектрофотометр Photometr 5010 v5+ [13] («Robert Riele GmbH &Co KG»), микропланшетный фото-метр Bio-Rad 680 [14] («Bio-Rad Laboratories»); экс-пресс-анализатор (рефлектометр) [15] NycoCard Rider II («Axis Shield»); регистратор Тромбодинамика Т-2 [16] («ГемаКор», Россия).…”

“…Активность факторов свертывания крови 3.1. Фактор II, % [6] Coagulation Factor II Deficient Plasma/«Siemens»…”

“…Протеин С, активность, % [8] Berichrom Protein C/«Siemens» 7.4. АПТВ ВА+, с, отношение [6] Экспресс-Люпус-тест/«Т-С» 0,84-1,11 (1,00) 7.5. АПТВ ВА-, с, отношение [6] 0,93-1,11 (1,02) n=48 [14] 24,0-51,1 (36,0) n=40 11.…”

“…АПТВ ВА+, с, отношение [6] Экспресс-Люпус-тест/«Т-С» 0,84-1,11 (1,00) 7.5. АПТВ ВА-, с, отношение [6] 0,93-1,11 (1,02) n=48 [14] 24,0-51,1 (36,0) n=40 11. Оценка пространственного роста сгустка фибрина «Тромбодинамика» [16] 11.1.…”

High hematocrit as a risk factor for venous thrombosis. Cause or innocent bystander?

“…The study by Braekkan and colleagues in this issue of the Journal is, therefore, a welcome contribution to the scientific literature. 2 Their results from the Tromsø study (a large health survey in Tromsø, Norway) show a hazard ratio of 1.25 per 5% rise in hematocrit. 2 In a category-based analysis, a hematocrit in the upper 20 th percentile was found to be associated with a 1.5-fold increased risk of venous thrombosis.…”