Chaps,
I’ve tried to make sense of the discourse that Paul shared with us about the ARUBA study. My reading of it is along the lines of…
If you’ve had a rupture of an AVM, then nobody is disputing the efficacy of surgical or endovascular or radiotheraputic intervention to reducing future risks. However, this entire article seems to me to be a set of disagreements between two sets of doctors as to how to determine whether interventions such as surgery or embolisation or radiotherapy are “better” at reducing future risk than merely treating symptoms “conservatively”. I’m not quite sure whether that conservative treatment means painkillers or anti-seizure medication, or just waiting for those symptoms to appear before then concluding that the other treatments should be started.
Both sets of doctors agree that the ARUBA study done between about 2007 and 2014 was flawed and possibly unbalanced. So although the results appeared to show that “conservative” management of unruptured AVMs was more successful than where intervention was taken, the way the study was done is cited as unbalanced and not to be relied upon.
The problem is that AVMs are quite rare and no two presentations are sufficiently alike for the probability of determining exact outcomes: whether to treat or not to treat. Both sets of doctors agree in their own ways that clear separation of results (as illustrated in figure 1) is unlikely. The problem, therefore, is how to set the scope for study such that people taking part are not disadvantaged by either conservative management or interventional treatment. In some cases, randomly allocating treatment would arrive at the wrong answer, where other knowledge suggests that it is perhaps obvious. The argument set out in the response is that interventional treatment is unproven and therefore the starting point should be “not to treat” but by randomly allocating patients 50% to treatment and 50% to continue with no treatment should be seen as an avoidance of surgical risk for the latter and the chance for participation in a trial for a better outcome for the others.
However, my reading of it is that it is all about semantics. Neither set of doctors is satisfied that there is useful, independent evidence one way or another that tells us whether intervention is the best thing to do, or not. Should a trial be undertaken including all types of AVM, or should the apparently obvious, extreme instances be excluded? – those where other work suggests that intervention is best should carry on receiving treatment and those where intervention would not today be recommended are also excluded from the 50% chance of being recommended treatment.
CONCLUSION: It is perfectly unclear whether treatment or “conservative management” is best for most unruptured AVMs.
Does that help at all? I know I’ve continued to use long words!
Best wishes,
Richard