I am frequently impressed with the writings of Ray Moynihan, and his article in this week’s BMJ is probably one of his best. It’s entitled “Surrogates Under Scrutiny” – not a title which immediately appealed to me because I mistakenly thought it would be an article about surrogate pregnancy. I was wrong! It refers to use of “surrogate” markers for health outcomes. I must confess I’ve never come across this use of the term before, but he relates it to The Institute Of Medicine’s report “Evaluation of Biomarkers and Surrogate Endpoints in Chronic Disease“.
This is, potentially, an enormously important article (or, at least, it’s a great introduction to an enormously important issue)
It’s a constant source of frustration to me that the reductionist, materialistic promotion of “evidence” in Medicine, seems to prioritise biomarkers, and to trivialise patient centred outcomes, or any attempt to capture the narratives of health and wellbeing. I now understand more clearly why.
It’s also a source of concern for me that human beings are consuming ever greater quantities of pharmaceuticals without any evidence that is producing greater health, wellbeing or happiness. Don’t get me wrong. Drugs can produce great changes in disease and, consequently, can open the opportunities for people to thrive, grow and experience better health. I wouldn’t like to see diabetics trying to get by without insulin for example. However, the limited view that only drugs can produce better health, strikes me as fundamentally naive. In fact, in many situations, the balance between potential harms and potential benefits has swung way far in the direction of harm. I now understand more clearly why we’re getting this wrong.
Let me just replicate for you here the closing paragraphs of Ray Moynihan’s article, because I don’t think I could put it better myself.
Shift from numbers to people
A major rethink of the role of surrogates in medicine is timely. Routinely approving and prescribing therapies on the basis of their effects on someone’s numbers, rather than their health, is increasingly seen as irresponsible and dangerous. And even when evidence suggests clinical benefits of popular “preventive” medicines for those at lower risks, a rational assessment reveals many people must be treated to prevent one adverse event, so most users gain no direct benefit despite years of treatment. The cost effectiveness of this approach is unsurprisingly in doubt. More disturbing still are the questions about whether some of the suggested clinical benefits are real or simply artefacts of sponsorship bias. The rigour of the evidence informed approach to medicine has in recent decades helped us all understand the limitations of relying on surrogates, and for one of its key architects—McMaster University professor Gordon Guyatt—this problem is both historical and cultural. He argues that central to putting American medicine on a scientific basis was the assumption that an understanding of biological mechanisms would translate into improved management of patients. And while medical students over a century later are still taught to focus on fixing a person’s biological numbers—whether it’s cholesterol or bone density—what is urgently required is a new approach that provides genuine improvement for the person. Understanding biological mechanisms and diagnosing by numbers has undoubtedly brought great benefits. Yet as the definitions of medical conditions relentlessly expand via that porous relationship between the science and business of healthcare, this fragmented reductionist approach is conferring multiple medical labels on vast swathes of healthy people, who are then treated with preventive drugs that won’t help most of them and may hurt many. The magic of numbers may help corporate profits and professional pride, but at what cost to the health of ordinary people who mistake a numerical benefit for a genuine one? Surely it’s time to ask if there might be a healthier new model for medicine based on far less harmful and costly ways to try to reduce human suffering.
Using proxy markers as a substitute for reality is sadly not limited to medicine. We see this “bait & switch” being used all the time in politics and policy-setting. It takes a lot of effort, as well as clarity of thought, to recognise it consistently as more often than not, even the best of us find it intellectually easier to go with the flow sometimes. In fact, if you point it out too regularly, the flow can turn against you…! 😉
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