The EASD and the ADA have worked over many years to produce joint guidelines and statements about the treatment of type 2 diabetes. Additionally the ADA publishes its ‘Standards of Care’ annually. All these documents are opinion pieces put together on the basis of evidence, experience and accepted practice. They are helpful, have a wide readership and are useful for clinicians, health-care workers, payers, hospitals, clinics and sometimes lawyers!
Nevertheless, it is worth asking ‘how do we know what we know?’. Indeed that question forms a significant branch of philosophy called ‘epistemology’. In diabetes we know much from trials and meta-analyses, from physiology and diagnostic techniques and clinical measurements. But how ‘true’ are the trials?
All major studies have had flaws – can we extract the truths?
Most of the science of how we treat diabetes comes from the building together of a coherent edifice of science. This edifice has some important corner-stones – the UKPDS (with coherent resonances from the DCCT), ADVANCE, ACCORD and the VADT. Beyond these generic trials we have drug-specific trials including RECORD (rosiglitazone), LEADER (liraglutide), and CANVAS (canagliflozin), and subsets of these trials examining specifics including SUSTAIN (once-weekly GLP1), PIONEER (oral semaglutide) and CREDENCE (renal protection of SGLT2s). Each of these trials gives a differing insight into our care of type 2 diabetes and none alone can inform us of the best course of action. Nevertheless, over the years we move towards a consensus, hoping that we also learn the wisdom of when to deviate from the strictures of dogma.