In my days as a junior doctor, when I was taught to use compression stockings for DVT treatment, I was taught that it was to help treat the existing DVT/reduce risk of DVT in the other leg. Whether this is the case or not I don’t know, but, many years later, I’ve just learned that actually the purpose (or at least one of the purposes) is to reduce the risk of post-thrombotic syndrome (long-term swelling of the leg with increased ulceration risk). And that there is conflicting evidence on whether it actually does that or not.
The reason this came up in this week’s issue of the BMJ is because a further study – the OCTAVIA study – has been done to look at the question of how long stockings should be used for if indeed they are used. A group of patients with DVTs who had been fine with wearing compression stockings for the first year post-DVT (which makes them something of a selected subgroup for starters, of course) were randomised to stop at 12 months or continue for 24 months, and the rates of post-thrombotic syndrome compared. They did come out as a little lower in the ‘continue’ group, with an NNT of 14, but the attached editorial (to which I linked above) points out that overall rates of post-thrombotic syndrome in that year were substantially higher than normal overall (though most cases were very mild, which makes me wonder whether the issue was that researchers were setting the bar for diagnosis too low).
So, the answer to ‘Can I stop wearing my stockings now, Doctor?’ from a patient one year post-DVT seems to be, currently, that there’s a bit of evidence that continuing for an extra year may reduce risk, but that it isn’t conclusive and must be weighed up against the inconvenience of wearing compression stockings for an extra year.