Venous thrombosis and prothrombotic factors in inflammatory bowel disease

Table 1 Risk of venous thrombosis in inflammatory bowel disease patients relative to non-inflammatory bowel disease patients

Ref.	Design	Population		Risk measure (95%CI)	Controlled variables
		IBD	Controls
Grip et al[6], 2000 Sweden	Retrospective cohort study Inpatients Records from 2 university hospitals	1253 patients	387 (significant age differences between the IBD cohort and controls)	Incidence rate of VTE 1.5/1000 IBD per year (comparable to the background population)
Bernstein et al[8], 2001 Canada	Retrospective cohort study Inpatients Manitoba Health administrative 1984-1997	5529 patients	Approximately 55000 year, age, gender and postal area of residence matched members of the general population	DVT RR 4.7 (3.5-6.3) CD RR 2.8 (2.1-3.7) UC PE RR 2.9 (1.8-4.7) CD RR 3.6 (2.5-5.2) UC
Miehsler et al[9], 2004 Austria	Retrospective cohort study Outpatients and inpatients Three outpatient clinics of Division of Gastroenterology and Hepatology	618 patients	707 age and gender matched controls	Incidence rate of VTE 6.2% IBD 1.6% Controls VTE aOR 3.6 (1.7-7.8) IBD	Operation, injuries, oral contraceptive use, pregnancy, body mass index and smoking
Bernstein et al[20], 2007 Canada	Retrospective cohort study Inpatients The Statistics Canada’s Health Person Oriented Information database 1994-2004	About 22000 to 25000 patients	About 2.5 to 3.2 million age and gender matched controls	VTE ≥ 50 yr old RR 1.3 (1.23-1.37) IBD < 50 yr old RR 1.57 (1.42-1.72) IBD
Huerta et al[10], 2007 United Kingdom	Prospective cohort study with nested case-control analysis Outpatients and inpatients General Practice Research Database - GPRD 1994-2000	6550 patients	10000 age, gender and year matched controls	VTE OR 1.84 (1.29-2.63) IBD
Nguyen et al[12], 2008 United States	Retrospective cohort study Inpatients Nationwide Inpatient Sample 1998-2004	116842 patients (73197 CD and 43645 UC patients)	522703 controls	VTE aOR 1.48 (1.35-1.62) DC aOR 1.85 (1.70-2.01) UC	Age, gender, calendar year, health insurance payer, comorbidity, presence of IBD related surgery, geographic location, and hospital characteristics
Ha et al[148], 2009 United States	Retrospective cohort study Outpatients and inpatients MarketScan Commercial Claims and Encounters database - Thomson Reuters 2001-2006	17487 patients (7480 CD and 9 968 UC patients)	69948 age, gender and index date matched controls	PVT aHR 6.2 (P < 0.05) IBD DVT aHR 2.3 (P < 0.0001) IBD PE aHR 1.7 (P < 0.001) IBD	Hypertension, diabetes, hyperlipidemia, and, in women, the use of contraceptives
Nguyen et al[14], 2009 United States	Retrospective cohort study Pregnant hospitalized women Nationwide Inpatient Sample 2005	3740 patients (2372 CD and 1368 UC patients)	4.21 million pregnant women	VTE aOR 6.12 (2.91-12.9) CD aOR 8.44 (3.71-19.2) UC	Maternal age, race/ethnicity, median neighbourhood income, comorbidity, health insurance, geographical region, hospital location and teaching status and caesarean delivery
Grainge et al[19], 2010 United Kingdom	Retrospective cohort study Outpatients and inpatients General Practice Research Database 1987-2001	13 756 patients (4835 CD and 6765 UC patients)	71672 age, gender, and general practice matched controls	VTE aHR 3.4 (2.7-4.3) IBD	Age, sex, body-mass index, smoking, cancer diagnosis and history of pulmonary embolism or deep vein thrombosis
Novacek et al[16], 2010 Austria	Retrospective cohort study Outpatients IBD patients from 14 Austrian centers specializing in the treatment of patients with IBD (2006-2008) and controls patients from 4 centers in Austria (1992-2008) 2006-2008	86 patients with history of unprovoked VTE	1255 controls with unprovoked VTE	Recurrence 5 yr after discontinuation of anticoagulation therapy aRR 2.5 (1.4-4.2) IBD	Age, gender, factor V Leiden, prothrombin G20210A mutation, high factor VIII (> 234 IU/dL), duration of anticoagulation and body mass index
Scarpa et al[147], 2010 Italy	Prospective case-control study Hospitalized patients who had major colo-rectal surgery Patients admitted for colorectal surgery in the institute of Clinica Chirurgica I of the University of Padova (Italy) 2004-2006	323 patients	432 controls	Incidence rate of VTE in surgical IBD patients vs surgical non IBD patients (both with prophylactic therapy) 1.9% vs 0% VTE with prophylactic therapy OR 5.9 (0.9-39.7) UC
Kappelman et al[13], 2011 Denmark	Retrospective cohort study and nested case-control study Danish National Patient Registry 1980-2007	49799 patients (14211 CD and 35 229 UC patients)	477504 age and gender matched members of the general population	All VTE HR 2.0 (1.8-2.1) IBD HR 2.2 (2.0-2.5) CD HR 1.9 (1.8-2.0) UC Unprovoked VTE HR 1.6 (1.5-1.8) IBD HR 2.0 (1.6-2.5) CD	Comorbidities and medications
Merrill et al[23], 2011 United States	Retrospective cohort study Surgical patients National Surgical Quality Improvement Program 2008	2249 patients	269119 patients without IBD who were hospitalized and underwent surgery	HR 1.5 (1.4-1.7) UC aOR 1.7 (1.3-2.2) IBD VTE aOR 2.03 (1.52-2.70) IBD	Age, gender, race/ethnicity, admitted from home, smoker, BMI > 30, medical history, clinical factor
Rothberg et al[22], 2011 United States	Retrospective cohort study Inpatients 374 US hospitals 2004-2005	814 patients	241924 controls	VTE aOR 3.11 (1.59-6.08) IBD	Age, gender, VTE prophylaxis, length of stay ≥ 6 d, primary diagnosis, comorbidities, cancer and treatments
Saleh et al[11], 2011 United States	Retrospective cohort study Inpatients National Hospital Discharge Survey 1979-2005	2932000 patients (1803000 CD and 1129000 UC patients)	918570000 age, gender matched controls	VTE HR 1.08 (1.06-1.09) CD HR 1.64 (1.62-1.66) UC
Sridhar et al[21], 2011 United States	Cross-sectional study Inpatients Nationwide Inpatient Sample 2010	148229 patients	17261952 controls	VTE (DVT, PE and/or PVT) aOR 1.38 (1.25-1.53) IBD	Hypertension, diabetes mellitus and hyperlipidemia
Bröms et al[15], 2012 Sweden	Retrospective cohort study Pregnant women Medical, Patient, and Prescribed Drug Registers of all residents in Sweden 2006-2009	1996 patients (787 CD and 1209 UC patients) who gave birth to a single infant	10773 women without IBD who gave birth to a single infant	VTE aRR 2.65 (0.65-10.1) CD (with inactive disease) aRR 3.78 (1.52-9.38) UC	Age, parity, smoking, body mass index and comorbidities

IBD: Inflammatory bowel disease; CD: Crohn’s disease; UC: Ulcerative colitis; VTE: Venous thrombosis; DVT: Deep venous thrombosis; PE: Pulmonary emboli; PVT: Portal vein thrombosis; aRR: Adjusted relative risk; aOR: Adjusted odds ratio; aHR: Adjusted hazard ratio.