A recent edition of the BMJ took a big focus on the issue of “surrogate outcomes” – in other words, changes in some lab tests instead of changes which matter to the patient.
Does this comment surprise you?
“In order to fully engage our patients in treatment decisions, we must understand how therapies affect outcomes that are important to them,”
It shouldn’t really, but in recent years, certain flavours of “evidence based” enthusiasts have completely dismissed patients reports of differences in their health experience. Often the patients reports are dismissed as either “anecdotes”, as “soft evidence”, or as “just feeling better” (ie not REALLY better – whatever that means!)
I think health is a subjective experience as well as a state of potential change in objective signs or measures. I’m delighted, therefore, to see these calls for a PRIORITY to be given to “outcomes which matter to patients”. After all, whose life is it?
Here are a couple of examples from the BMJ articles -
Citing the 2010 report from the US Institute of Medicine, which urged much greater caution in how we use surrogates, Moynihan called for a shift “from numbers to people” so that patients and doctors stop mistaking “a numerical benefit for a genuine one.”
From their perspective within the world of diabetes they warn that surrogates like HbA1c generally show much larger responses to treatment than “hard” outcomes that matter to patients, such as renal and visual impairment or quality of life.
Why are they arguing for this?
What’s the problem with surrogates?
Why have doctors become so invested in surrogate markers? The main reason is that the evidence base is built from trials that focus on the effect on surrogates. Since they respond sooner than outcomes that are important to patients, surrogates are better suited as end points in clinical trials that need to be completed quickly and at low cost. Evidence that builds in this way shapes practice and policy. Consequently, clinicians see this evidence converted into guidelines, quality of care measures, and pay for performance targets. We could speculate that the short term goals of the drug industry contribute to the predominance of surrogates in clinical practice. But this is an oversimplistic analysis. A historical view points more broadly to an alliance of public health advocates, scientists and clinicians, professional societies, and test and treatment companies who see their interests coincide. Idolisation of the surrogate end point has turned doctors away from the focal point of patient centred therapy based on hard end points. (Yudkin)
We need to change this primarily to reduce the potential harms caused by promoting drugs which don’t actually make patients lives better, but where the side effects can be fatal (think flecainide or rosiglitazone), but also….
Focusing on outcomes that matter to patients should improve decision making and patient engagement. It should also stop us spending money on treatments that deliver minimal or no benefit.
Nobody can define “benefit” better than the patient whose life is being affected by the disease and by the treatment.
Read Full Post »