Those labouring with this Disease, piss a great deal more than they drink. Authors who affirm the drink to be little or nothing changed are very far from the truth, because the urine very much differed both from the drink taken in and also in being wonderfully sweet as if it were imbued with honey or sugar.
THOMAS WILLIS (1621–75), THE PISSING EVIL
Diabetes comes from a Greek word meaning ‘to pass or flow through’ (i.e. excessive urination) and mellitus means ‘sweet’. It is a disease caused by a relative or absolute deficiency of insulin.
There are two main types of diabetes (see TABLE 20.1).
Table 20.1Clinical differentiation between type 1 and type 2 diabetes |Favorite Table|Download (.pdf) Table 20.1 Clinical differentiation between type 1 and type 2 diabetes
| ||Type 1 ||Type 2 |
|Relative frequency (approx.) ||10–15% ||85–90% |
|Peak age incidence ||10–30 years ||>40 years |
|Age of onset ||Usually young <20 ||Usually middle-aged >40 |
|Onset ||Rapid ||Insidious/slow |
|Presentation ||Polyuria, polydipsia weight loss ||Milder symptoms, often asymptomatic |
|Weight at onset ||Low (thin) ||High (obese) |
|Ketoacidosis ||Yes ||Rare |
|Familial ||Weak ||Strong |
|Insulin status ||Deficient ||Resistant |
Type 1 has an autoimmune causation which is also responsible for a late-onset form known as late onset autoimmune diabetes in adults (LADA).
DIABETES: A REAL MASQUERADE
The onset of type 2 diabetes can be subtle and by stealth. Studies have demonstrated that it takes, on average, 7–9 years before a patient is diagnosed.1 At any one given time almost half of patients with type 2 diabetes are undiagnosed. In 2014–15, around 5% of Australians had diabetes.2 A further 16% have impaired fasting glucose or impaired glucose tolerance.3 Very importantly, about 35% of newly diagnosed diabetic patients are already harbouring complications of diabetes.1 The challenge for GPs is to be on constant lookout for these patients, especially those at risk. Type 2 diabetes is becoming more prevalent in industrial countries—partly due to the ageing population and partly because our lifestyle encourages us to ‘eat more and walk less’.3 Furthermore, 60% of our population are overweight or obese.
Complications occur in type 2 diabetes as well as in type 1.
Table 20.2Causes of secondary diabetes