Thromboembolic complications in IBD

Thromboembolic complications in IBD

Athos Bousvaros MD, MPHAssociate Director, IBD Center

With gratitude

Naamah Zitomersky Cameron Trenor

Thrombosis and IBD: A call for improved awareness and prevention. IBD Journal 2011 17:458

Menno Verhave

Overview

• Pathophysiology• Risks of venous thromboembolism

– Relative– Absolute

• Risk factors• Workup of thromboembolic event• Prophylaxis• Treatment

Arterial vs. venous thromboembolism

• Arterial– Clot in an artery (carotid, coronary, SMA)– Rare in younger patients (under 40 years)– Preventable with antiplatelet drugs (ASA)

• Venous– Clot in venous system– Deep venous thrombosis (usually in leg or arm)– Preventable with anticoagulation (heparin, coumadin)

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Coagulation cascade

ANTI-THROMBIN

PROTEIN SPROTEIN C

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Risk factors in the general population

• Hereditary thrombophilias– Factor V Leiden mutation

• 5% of Caucasians, 2% Hispanics, 1% African Americans– Prothrombin gene mutation (G20210A)

• 2% of Caucasians– Protein C, Protein S, Antithrombin 3 deficiencies

• Environmental causes– Smoking, oral contraceptives– Surgery, immobility

Why are IBD patients especially at risk?

• Inflammation and disease activity– Increased fibrinogen– Increased D-dimer– Increased factors V, VIII, IX

• Prothrombotic antibodies (antiphospholipid)• Endothelial damage• Increased homocysteine• Prothrombotic medications

– thalidomide

Inflammation is the Most Common Risk Factor; DVT without a Risk Factor is Rare in Children

Lupus anti-coag=40%

Central venous catheter=24%

Acute infec-tion=13%

Chronic in-flamm=10%

Other=8%

Idiopathic=5%

No Risk Factor

Lupus Anticoag

Infl

Infec

NEJM 2004;351:1081-8.

(n=82)

CVL

Venous thromboembolism (VTE) in inflammatory bowel disease

• Relative risk is high– Six fold greater hazard ratio in < 20 years old*– Mainly in patients with flares**

• Absolute risk is low– 2811 IBD patients recruited over 2.5 yrs***– 116 (4%) of patients developed de novo VTE

• Mean age 42 years– Risk of recurrence high if anticoagulation stopped

*Kappelman et al; Gut 2011 Nylund et al; JPGN 2013** Grainge et al, Lancet 2010*** Novacek, Gastro 2010

What complications occur with increased frequency in adults?

• Meta analysis of over 200,000 patients – increased risk of venous, but not arterial events.– Deep venous thrombosis RR 2.4– Pulmonary embolism RR 2.5– Ischemic heart disease RR 1.3– Mesenteric ischemia RR 3.4

Fumery et al, J. Crohn’s Colitis 2013

IBD Clot rates – Boston Children’s

All kids IBD kids

VTE risk 1/10,000/y ~3x higher

VTE in Inpatients

0.58% (58/10,000)

1.5% (8/532)(1.7% incl. arterial)

CVL 4.5% @ CHB* 3.8% (4/104)

*3.82 symptomatic events per 1000 catheter days

Zitomersky et al, JPGN 2013; 57:343-7

A major source of morbidity

IVC clot needing filter in severe UC

Is heparin prophylaxis indicated?

• Not in outpatients, unless another reason– “Prophylaxis would be needed for 312 person-years of IBD flares

to prevent one person developing venous thromboembolism” – G. Nguyen, Lancet

• Yes in inpatients– Included in AGA physician performance measure set, but only

35% of gastroenterologists use it.*– “…heparin has an important role in prophylaxis against

thromboembolism in patients admitted to hospital with severe colitis”

– Kornbluth and Sachar, ACG Guideline 2010

*Tinsley, J. Clin Gastroenterol 2013

Prophylactic Anticoagulation for High Risk Colitis patients

No personal or strong family history of bleeding

Pre-pubertal or < 40kg

Enoxaparin 0.5 mg/kg BID

Post-pubertal or > 40kg

Enoxaparin 40 mg daily

• Continue anticoagulation until either:– Discharge– Resolution of colitis, or– Baseline mobility, if post-op

The “ouch” factor

Colitis: New diagnosis or Admission• Review family history for thrombosis AND

bleeding• Address dehydration• Address immobility (PT consultation, plan for

ambulation)• Alternatives to combined oral contraception• Counsel about smoking, inactivity, long travel• Consider

– factor VIII– D-dimer– lupus anticoagulant– anti-cardiolipin and anti-2 glycoprotein 1 antibodies

Proposed High Risk Definition

*awareness if elevated factor VIII, D-dimer, isolated APLA#Known thrombophilia = factor V Leiden, prothrombin gene mutation, low protein C/S or antithrombin function, persistent APLA >40 for >12 weeks

Inpatient colitisOR

Major surgery

Personal history thrombosis,1st degree family history,

Known thrombophilia,#

OCPs,Smoking > 1ppd,

BMI > 35 OR

PICC/Broviac/Port-a-Cath(especially if ASD)

thalidomide

High Risk

Evaluation of DVT

• High index of suspicion– Headache, vomiting– Extremity swelling

• Labs– D-dimer excellent negative predictive value

• Imaging– Ultrasound of extremity and femoral veins– MR or MR venography preferred for CNS– Spiral CT for pulmonary embolism– Cardiac echocardiogram for patent foramen

Therapy of clots (adult and pediatric)

• Unfractionated heparin– 75 U/kg bolus– 18 U/kg/hour– Goal anti-Xa level, 0.3-0.5 U/ml

• Low molecular weight heparin (enoxaparin)– 1mg/kg sc bid– Goal anti-Xa level 0.5-1 U/ml

• Warfarin for long term management?• Colectomy may be life-saving

– Timing of colectomy is tricky

Additional therapy

• Catheter directed thrombolysis• Inferior vena cava filter

– Protect against pulmonary emboli• Surgical thrombectomy

– When thrombolysis contraindicated• Is a large clot complicating severe colitis an

indication for colectomy? – What is optimal timing for the colectomy?– Control colitis medically, treat clot, then operate

Is heparin safe in IBD?Severe bleeding on anticoagulation is rare

Treatment Prophylaxis

All adults 2% 3%

All kids 2% 4.3% (trauma)

CHB 2.5% (4/162)4.1% HR (2/49)

???

CHB IBD 11.1% (1/9) ???

Conclusions• All patients with IBD are probably at an increased

risk of clots during disease flares– Absolute risk is low

• The highest risk group appears to be inpatients with severe colitis – Inflammation– Immobility

• Prophylaxis with LMWH is indicated in patients hospitalized for severe colitis or post-op – Enoxaparin, 40 mg SQ daily in adults