Glycemic control and diabetes: today's evidence

This paper has the potential to be pretty important:

Intensive glycaemic control for patients with type 2 diabetes: systematic review with meta-analysis and trial sequential analysis of randomised clinical trials

The article is free online but let me quote from the conclusion:

Intensive glycaemic control does not seem to reduce all cause mortality in patients with type 2 diabetes. Data available from randomised clinical trials remain insufficient to prove or refute a relative risk reduction for cardiovascular mortality, non-fatal myocardial infarction, composite microvascular complications, or retinopathy at a magnitude of 10%. Intensive glycaemic control increases the relative risk of severe hypoglycaemia by 30%.

This is actually quite important. It is very difficult for patients to maintain low levels of blood glucose, with consequences in both quality of life and adverse events. Tight glycemic control, for example is the reason that some policy makers have concerns about diabetics driving (due to worries about hypoglycemic attacks).

Given the difficulty of getting diabetics to adhere to tight glycemic control (and concerns about issues like driving), perhaps we should be more cautious in pushing tight control? More interestingly, we should ask why this association seems non-linear, as it is obvious that objectively poor glycemic control is very cardiotoxic.

But this was a very interesting paper for highlighting what we do and not not know.

Epidemiology is about communication

This article highlights the critical importance of continuing to try and communicate evidence-based medical information:

Most pancreatic cancers are aggressive and always terminal, but Steve was lucky (if you can call it that) and had a rare form called an islet cell neuroendocrine tumor, which is actually quite treatable with excellent survival rates — if caught soon enough. The median survival is about a decade, but it depends on how soon it’s removed surgically. Steve caught his very early, and should have expected to survive much longer than a decade. Unfortunately Steve relied on a diet instead of early surgery. There is no evidence that diet has any effect on islet cell carcinoma. As he dieted for nine months, the tumor progressed, and took him from the high end to the low end of the survival rate.

Why did he do this? Well, outsiders like us can’t know; but many who avoid medical treatment in favor of unproven alternatives do so because they’ve been given bad information, without the tools or expertise to discriminate good from bad.

Everyone would prefer to avoid surgery -- especially painful, high-risk surgery with an uncertain prognosis. But this seems to be a clear case where better advice could have made a real difference. Unfortunately, the literature is full of spurious findings and it can be hard for even experts to sort these issues out.

The ultimate goal of Epidemiology is to give patients the best (high-quality) evidence available in order to assist them in making optimal decisions. We'll never know if the advice given to Steve Jobs was good or bad, but stories like this highlight how important it is to keep focusing on communication.