The quality of evidence is downgraded by study limitations (lack of blinding), by inconsistency (variability in results), and by imprecise results (wide confidence intervals).
A Cochrane review included 10 studies with a total of 2 361 subjects that evaluated compression therapy. Only 5 studies were used in meta-analysis owing to differences in intervention types and lack of data. Three studies compared elastic compression stockings with a pressure of 30-40 mm Hg at the ankle versus no intervention.Two studies compared elastic compression stockings (pressure 20 to 40 mmHg) versus placebo stockings.
| Outcome | Relative effect (95% CI) | Assumed risk: No compression/placebo | Corresponding risk: Compression (95% CI) | Participants (studies) |
|---|---|---|---|---|
| Any PTS | RR 0.62 (0.38 to 1.01)* | 400 per 1000 | 248 per 1000 (152 to 404) | 1 393 (5) |
| Severe PTS | RR 0.78 (0.53 to 1.15)* | 86 per 1000 | 67 per 1000 (46 to 99) | 1 224 (4) |
| Recurrence of DVT** | RR 0.94 (0.69 to 1.28) | 118 per 1000 | 111 per 1000 (81 to 151) | 1 224 (4) |
Overall, use of elastic compression stockings led to a clinically significant but statistically non-significant reduction in the incidence of post-thrombotic syndrome, no reduction in the incidence of severe PTS, and no difference in DVT recurrence (table ). Two studies evaluated effects of compression in the acute phase versus no compression treatment and found no differences in the incidence of PTS (RR 0.76, 95% CI 0.49 to 1.16; n=101). One study reported that thigh-length stockings did not provide better protection against development of PTS than knee-length stockings (RR 0.92, 95% CI 0.66 to 1.28; n=267). Another study reported that wearing compression stockings for 2 years seemed to be superior to wearing them for 1 year in terms of PTS incidence. Two of the 10 included studies described patient satisfaction and quality of life, using different measurement systems. The first study showed significant improvement in well-being and DVT-related quality of life with compression treatment (P < 0.05) compared with bed rest, and the second study showed no differences in quality of life scores between compression and placebo groups. Four studies poorly reported side effects that included itching, erythema, and other forms of allergic reaction and described no serious adverse events. Compliance with wearing of compression stockings was generally high but varied across studies.
A Cochrane review