Type II diabetes is a serious chronic condition that can have debilitating complications and affect patient's quality of life severely. Simply put it is characterised by a heightened level of blood glucose, because of the body's inability to process sugar or glucose sufficiently. This has several consequences as it increases the risk that (severe) complications will ensue such as stroke, heart attack, blindness, kidney failure, neuropathic pain and amputation. Diabetes treatment is not (yet) aimed at curing diabetes, but the aim of treatment is to normalise the blood glucose and lipid levels in the blood as much as possible so that the risks of developing these complications is reduced. Successful treatment would find the optimal point between reducing the risks of the disease and the harm from the side effects of the treatment.

Type II diabetes is distinct from type I diabetes: type I is a condition with a predominantly auto-immune component where the patients are not able to produce any insulin and are dependent on external injections of insulin. Type I diabetes will not be covered in this book. For patients with type II diabetes, the treatment is evolving fast and new medication is coming onto the market every year. The challenge in drafting medical guidelines is to provide up-to-date advice while being mindful of the cost of new treatments versus the health benefits gained.

The treatment of diabetes recommended in guidelines is variable but often involves one or more of the following steps: providing patients with information/advice to lose weight; a diet; a drug to lower blood glucose, moving on to two or even three drugs lowering blood glucose and, finally, insulin by injection possibly in combination with medication to lower blood glucose. This treatment pathway is thus one that increases in severity to help control the blood sugar levels of a diabetes patient. The treatment of diabetes is, however, related to how long a person has had diabetes, the age of the patient and the other healthcare conditions a patient might suffer from. In designing diabetes guidelines, the group members must decide when to intensify treatment and which combination of drugs should be provided at the different stages of treatment.