STUDY LOOKS AT THE EFFECT OF COMPRESSION STOCKINGS IN PREVENTING POST-THROMBOTIC SYNDROME (DEC 2013)
Post-thrombotic syndrome occurs in up to one-third of patients who have been diagnosed with a deep vein thrombosis (DVT)
syndrome may include leg swelling, pain, leg ulcers, skin discoloration, leg heaviness, and venous insufficiency depending on the severity. Compression stockings are thought to help prevent the
syndrome, and current AHA guidelines recommend that patients wear knee-high, graduated elastic
compression stockings (30 - 40 mmHg at the ankle) daily for 2 years after their DVT to prevent post-thrombotic syndrome.
- PubMed abstract]
- The SOX trial enrolled 410 patients with first-diagnosed proximal DVT
- Main inclusion criteria: first symptomatic, proximal DVT (with or without distal DVT or pulmonary embolism) confirmed by ultrasound within the previous 14 days
- Main exclusion criteria: received thrombolytic therapy for the DVT
- Baseline characteristics: average age 55 years; average BMI 29
- Patients were randomized to one of two groups:
- Group 1 (410 patients): 30 - 40 mmHg graduated elastic compression stockings started within 2 weeks of DVT diagnosis
- Group 2 (396 patients): Placebo stockings with 5mmHg of pressure started within 2 weeks of DVT diagnosis
- Stockings were replaced every six months or sooner if torn or leg size changed
- PRIMARY OUTCOME: The primary outcome was diagnosis of post-thrombotic syndrome (at least 6 months after DVT diagnosis) using Ginsberg’s criteria
(leg pain and swelling of ≥1 month duration)
- After two years of follow-up, the following was seen:
- There was no significant difference between the 2 groups for the primary outcome (Group 1 - 14.2%, Group 2 - 12.7%, HR 1.13, CI 0.73 - 1.76)
- In a per-protocol analysis that included patients who reported frequent use of their stockings, there was no significant difference
between the two groups for the primary outcome
- There was no significant difference between the groups for occurrence of leg venous ulcers, recurrent venous thromboembolism, or quality of life
- Compliance with stocking use was about 56% at 2 years
- Findings: From 2004 to 2010, 410 patients were randomly assigned to receive active ECS and 396 placebo ECS. The cumulative incidence of PTS was 14·2% in active ECS versus
12·7% in placebo ECS (hazard ratio adjusted for centre 1·13, 95% CI 0·73-1·76; p=0·58). Results were similar in a prespecified per-protocol analysis of patients who reported frequent use of stockings.
This well-done study found no benefit of elastic compression stockings in preventing post-thrombotic syndrome.
This calls into question current AHA guidelines which recommend compression stockings for 2 years post-DVT to prevent post-thrombotic syndrome. In their discussion, the authors note that other
studies with compression stockings have shown a benefit in preventing post-thrombotic syndrome, but these studies used open-label designs (control group received nothing), and this likely
biased their outcomes. In conclusion, there is no good evidence that compression stockings prevent post-thrombotic syndrome, and they should not be recommended.