Infections and inflammatory diseases as risk factors for venous thrombosis A systematic review

Inflammation and venous thrombosis are intertwined. Only in the recent 15 years clinical epidemiological studies have focussed on inflammatory or infectious diseases as risk factors for venous thrombosis. Although a few reviews and many case reports or studies on these topic has been written, a review reporting relative or absolute risks for venous thrombosis has not been published yet. We performed a systematic review using Medline, Pubmed and Embase and found 31 eligible articles. Inflammatory bowel disease, ANCA-associated vasculitis, infections in general and more specifically, human immunodeficiency virus, pneumonia and urinary tract infections are associated with an increased risk of venous thrombosis

Active cytomegalovirus infection in patients with acute venous thrombosis:A case-control study

Infectious diseases have been associated with venous thrombosis (VT) [1]. Several case-studies described active cytomegalovirus infection in patients with VT [2-6]. In this case-control study, we detected five cases with active cytomegalovirus infection and VT, and none in the control group. All were female, below 37 years of age, and had another acquired risk factor for VT. This may imply that active cytomegalovirus infection contributes to a procoagulant state in young subjects with other mild risk factors for VT

Incidence of a first venous thrombotic event in people with HIV in the Netherlands:a retrospective cohort study

BACKGROUND: The risk of venous thrombotic events is elevated in people with HIV, but overall risk estimates and estimates specific to immune status and antiretroviral medication remain i mprecise. In this study, we aimed to estimate these parameters in a large cohort of people with HIV in the Netherlands. METHODS: In this retrospective cohort study, we used the Dutch ATHENA cohort to estimate crude, age and sex standardised, and risk period-specific incidences of a first venous thrombotic event in people with HIV aged 18 years or older attending 12 HIV treatment centres in the Netherlands. Crude and standardised incidences were compared with European population-level studies of venous thrombotic events. We used time-updated Cox regression to estimate the risk of a first venous thrombotic event in association with HIV-specific factors (CD4 cell count, viral load, recent opportunistic infections, antiretroviral medication use) adjusted for traditional risk factors for venous thrombotic events. FINDINGS: With data collected from Jan 1, 2003, to April 1, 2015, our study cohort included 14 389 people with HIV and 99 762 person-years of follow-up, with a median follow-up of 7·2 years (IQR 3·3-11·1). During this period, 232 first venous thrombotic events occurred, yielding a crude incidence of 2·33 events per 1000 person-years (95% CI 2·04-2·64) and an incidence standardised for age and sex of 2·50 events per 1000 (2·18-2·82). CD4 counts less than 200 cells per μL were independently associated with higher risk of a venous thrombotic event: adjusted hazard ratio (aHR) 3·40 (95% CI 2·28-5·08) relative to counts of 500 cells per μL. A high viral load (aHR 3·15, 95% CI 2·00-5·02; >100 000 copies per mL vs <50 copies per mL) and current or recent opportunistic adverse events (2·80, 1·77-4·44) were also independently associated with higher risk of a venous thrombotic event. There were no associations between any specific antiretroviral drugs and risk of a venous thrombotic event. Rates associated with pregnancy (9·4, 95% CI 4·6-17·3), malignancy (16·7, 10·6-25·1), and hospitalisation (24·4, 19·1-30·6) were lower than primary thromboprophylaxis thresholds suggested by the respective guidelines. INTERPRETATION: Our findings support neither prescribing primary outpatient thromboprophylaxis nor avoiding any type of antiretroviral medication in people with HIV at high risk of a venous thrombotic event. FUNDING: Dutch Ministry of Health, Welfare and Sport