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The SOX Trial: Compression Stockings to Prevent the Post-Thrombotic Syndrome

Phase 3
Completed
Conditions
Deep Venous Thrombosis
Interventions
Device: Knee-length, graduated elastic compression stocking
Device: Knee-length, placebo stocking
Registration Number
NCT00143598
Lead Sponsor
Sir Mortimer B. Davis - Jewish General Hospital
Brief Summary

The purpose of this study is to determine whether elastic compression stockings used for 2 years are effective in preventing the post-thrombotic syndrome in patients with symptomatic proximal deep venous thrombosis.

Detailed Description

The post-thrombotic syndrome (PTS) is a frequent, burdensome and costly condition that occurs in about one third of patients after an episode of deep vein thrombosis (DVT). Affected patients have chronic leg pain and swelling, and sometimes develop skin ulcers. At present, there is little to offer for the treatment of this condition. Prevention of PTS is the key to reducing its burden on patients and society. Elastic compression stockings (ECS) could be helpful in preventing PTS, however data on their effectiveness are scarce and conflicting.

Comparison(s): Knee-length, 30-40 mm Hg (Class II), graduated ECS worn on the DVT-affected leg daily for 2 years compared to knee-length, inactive (i.e. no compression) stocking, identical in appearance to active ECS, worn on the DVT-affected leg daily for 2 years.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
806
Inclusion Criteria
  • Consecutive patients with a first, symptomatic, objectively confirmed proximal DVT diagnosed within the last 14 days (with or without concurrent distal DVT or pulmonary embolism)
  • Who have no contraindications to standard treatment with heparin and/or warfarin, and
  • Who provide informed consent to participate
Exclusion Criteria
  • Contraindication to compression stockings
  • Limited lifespan (estimated < 6 months)
  • Geographic inaccessibility preventing return for follow-up visits
  • Inability to apply stockings daily and unavailability of a caregiver to apply stockings daily
  • Treatment of acute DVT with thrombolytic agents

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Active ECSKnee-length, graduated elastic compression stockingActive Elastic Compression Stockings (ECS) 30-40 mm Hg compression at the ankle.
Placebo ECSKnee-length, placebo stockingPlacebo stockings with identical appearance to Active ECS and with \< 5 mm Hg compression at the ankle.
Primary Outcome Measures
NameTimeMethod
Incidence of Post-thrombotic Syndrome (PTS)During 2-year follow up
Secondary Outcome Measures
NameTimeMethod
Incidence of Objectively Confirmed Recurrent Venous Thromboembolism (VTE), Death From VTE and Major BleedingDuring 2-year follow up
Severity of PTS, Including Incidence of Venous Ulcer6-24 months.

Highest Villalta at or after 6 month visit

The Villalta Scale for assessment of the post-thrombotic syndrome The Villalta scale has a range of 0-33. A Villalta scale score \>4 indicates post-thrombotic syndrome (severity of post-thrombotic syndrome is categorized as 5-9 points, mild; 10-14 points, moderate; \>14 points or presence of an ulcer, severe).

Higher values signify worse outcome. Points on each item in the scale are simply summed to a total score.

Quality of Life24 months

The SF-36 is a well-validated generic quality-of-life (QOL) instrument. It includes questions on both physical and mental health. Higher scores indicate a better QOL. The VEINES-QOL is a venous-disease specific QOL measure that consists of 25 items that quantify venous disease effect on QOL, and an embedded symptom sub-questionnaire (VEINES-Sym) with 10 items that measures venous symptoms. Higher scores are associated with better QOL.

The VEINES-QOL/Sym and SF-36 use the standard method for scoring questionnaires with items with different response scales that is now routinely used. Raw scores are first transformed to z score equivalents (mean, 0; standard deviation, 1), which then are transformed to T scores (mean, 50; standard deviation, 10) to give an easily understood range of scores. A person-specific estimate is imputed for any missing item in cases where the patient answered at least 50% of the items in the scale.

Trial Locations

Locations (25)

The Ottawa Hospital, Civic Campus

🇨🇦

Ottawa, Ontario, Canada

University Health Network - Toronto General Hospital

🇨🇦

Toronto, Ontario, Canada

Duke University Medical Center

🇺🇸

Durham, North Carolina, United States

Henry Ford Health Systerm

🇺🇸

Detroit, Michigan, United States

Hamilton Health Sciences - General Hospital

🇨🇦

Hamilton, Ontario, Canada

QE II Health Sciences Centre

🇨🇦

Halifax, Nova Scotia, Canada

London Health Sciences Centre

🇨🇦

London, Ontario, Canada

Sunnybrook & Women's College Health Sciences Centre

🇨🇦

Toronto, Ontario, Canada

Centre hospitalier affilié universitaire de Québec, Hôpital de l'Enfant-Jésus

🇨🇦

Quebec City, Quebec, Canada

St. Boniface General Hospital

🇨🇦

Winnipeg, Manitoba, Canada

Oklahoma University Health Sciences Center

🇺🇸

Oklahoma City, Oklahoma, United States

Hamilton Health Sciences - Chedoke Division

🇨🇦

Hamilton, Ontario, Canada

Hamilton Health Sciences - Henderson General Hospital

🇨🇦

Hamilton, Ontario, Canada

Hôpital Maisonneuve-Rosemont

🇨🇦

Montreal, Quebec, Canada

Royal Victoria Hospital - McGill University Health Centre

🇨🇦

Montreal, Quebec, Canada

Sir Mortimer B. Davis - Jewish General Hospital

🇨🇦

Montreal, Quebec, Canada

St. Mary's Hospital Center

🇨🇦

Montreal, Quebec, Canada

Montreal General Hospital - McGill University Health Centre

🇨🇦

Montreal, Quebec, Canada

Hôpital du Sacré-Coeur de Montréal

🇨🇦

Montreal, Quebec, Canada

Victoria Heart Institute Foundation

🇨🇦

Victoria, British Columbia, Canada

Centre Hospitalier de l'Université de Montréal - Hôpital Notre-Dame

🇨🇦

Montreal, Quebec, Canada

Centre Hospitalier Pierre-Boucher

🇨🇦

Longueuil, Quebec, Canada

Centre Hospitalier de l'Université de Montréal - Hôpital Hôtel-Dieu

🇨🇦

Montreal, Quebec, Canada

Hamilton Health Sciences - McMaster University Medical Centre

🇨🇦

Hamilton, Ontario, Canada

St. Joseph's Healthcare Hamilton

🇨🇦

Hamilton, Ontario, Canada

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