Wednesday, August 31, 2005

Sensational Headlines: Metabolic Syndrome and the ADA

In recent days a number of headlines have suggested that the American Diabetes Association (ADA), in a joint statement with the European Association for the Study of Diabetes (EASD), have stated that Metabolic Syndrome doesn't exist.

Based on the headlines, I, too, was outraged at the suggestion that one of the leading organizations for diabetes would take such an erroneous position. But, as is often the case, the published review does not synch with the headlines. This is one reason why it is so important that we look at the actual primary sources rather than headlines reporting on the primary! In this instance, the media has sensationalized the published paper, leading to a gross misrepresentation of what the review actually says and why it was published.

Let's take a look at the actual publication in Diabetes Care: The Metabolic Syndrome: Time for a Critical Appraisal

The review opens with the critical paragraph:

The term "metabolic syndrome" refers to a clustering of specific cardiovascular disease (CVD) risk factors whose underlying pathophysiology is thought to be related to insulin resistance. Since the term is widely used in research and clinical practice, we undertook an extensive review of the literature in relation to the syndrome’s definition, underlying pathogenesis, and association with CVD and to the goals and impact of treatment. While there is no question that certain CVD risk factors are prone to cluster, we found that the metabolic syndrome has been imprecisely defined, there is a lack of certainty regarding its pathogenesis, and there is considerable doubt regarding its value as a CVD risk marker. Our analysis indicates that too much critically important information is missing to warrant its designation as a "syndrome." Until much needed research is completed, clinicians should evaluate and treat all CVD risk factors without regard to whether a patient meets the criteria for diagnosis of the "metabolic syndrome."

Basically, the statement makes sense - we know from the evidence (which dates back to the 1980's and continues through the present) of the existence of metabolic-type syndrome: a cluster of oft-related components - obesity, hypertention, dislypidemia and insulin resistence.

What is presently lacking, and what the paper highlights, is:

  • A solid, working definition that has consensus/agreement
  • A thoroughly-understood pathogenesis (that is what happens to someone with the syndrome)
  • An agreed upon treatment course for those diagnoised
  • A standard of care for those diagnosed
  • Effective strategies that can help prevent metabolic syndrome

And these are the core of the paper published - the lack of adequate evidence about what to do with a patient presenting with the components in the cluster of symptoms known as "metabolic syndrome." Nowhere in this paper is there a denial that there is real medical problem in people with this cluster of symptoms.

In reviewing the paper published it comes to light that the ADA and EASD are concerned that without the critical scientific data, we're missing critical information to guide the best treatment.

They call for additional research with specific attention directed toward:

  • A critical analysis of how the syndrome is defined. Are all risk factors equally important? Do some combinations (of two, three, or four factors) portend greater CVD risk than others?
  • A definition of the syndrome, in which variables have defined lower and upper cut points or that uses continuous variables in a multivariate score system (e.g., Framingham/UKPDS risk engine).
  • An evidence-based analysis assessing the rationale and value of adding (or replacing) other CVD risk factors (e.g., age, CRP, family history, a direct measure of insulin resistance) to the definition.
  • An assessment of CVD risk in subjects with combinations of intermediate phenotypes only (e.g., IFG/IGT, mildly elevated triglycerides, blood pressure 120–140 mmHg) and who have, or don’t have, insulin resistance or hyperinsulinemia.
  • An aggressive research agenda to identify the underlying cause(s) of the CVD risk factor clustering.

So, while the headlines blared at us that the ADA has suddenly taken to the idea that Metabolic Syndrome doesn't exist - the actual publication shows that the ADA is concerned with a lack of definition, pathogenesis and treatment; and strongly states we must use an evidence-based approach to tackle these issues. I have to say I agree!

If you're one of millions already diagnoised with Metabolic Syndrome, this paper does not sweep away your diagnosis or diminish the risks you're facing. We know, based on the evidence to date, that the most effective way to reduce risks right now, in those with Metabolic Syndrome (that is with components of the cluster of symptoms) is - weight reduction, adequate nutrition, exercise and reduction of stress.

With regard to nutrition, we now also know through Level 1 evidence that carbohydrate restriction is the fastest drug-free method for addressing the "cholesterol" (e.g. HDL and triglyceride) and "insulin" issues seen in the vast majority of those with the condition.

1 comment:

  1. Terrific post, Regina--I love how you're able to decipher these often difficult and tedious reports for me! I do hope more evidence becomes evident(that was awkward, right?) that Metabolic Syndrome IS the main culprit in these modern-day diseases (heart disease, high cholesterol, type two diabetes, high blood pressure, etc.) It's something I've always felt strongly about--that all of the above are merely symptoms of something bigger going on out there--and that the answer, believe it or not (as you stated) is carbohydrate restriction.
    Great post;-)