Management of type 2 diabetes focuses on lifestyle interventions, lowering other cardiovascular risk factors such as obesity/smoking, and maintaining blood glucose levels in the normal range. Various medications exist which aim to do this, failing which, insulin therapy may be required.
>Sulphonyureas, e.g. Tolbutamide, Glibenclimide, Gliclazide, Chlorpropramide
Mainly act to promote insulin secretion in response to glucose or other secretagogues. Ineffective in patients without some beta-cell function, ie. young ketotic patients.Used with care in patients with liver disease. All these drugs encourage weight gain so not first choice for obese patients. Hypoglycaemia is the most common and dangerous side effect, especially as action of the drug persists often for over 24hours. >Biguanides e.g. Metformin.
Unclear mechanism. Reduces gluconeogenesis, thus suppressing hepatic glucose output, and increases insulin sensitivity. It does not induce hypoglycaemia in normal volunteers and can be used in combinations when monotherapy is not sufficient. Does not induce weight gain so good for obese patients. Side-effects include anorexia, epigastric discomfort, and diarrhoea. Contraindicated in the presence of hepatic or renal disease due to some cases of lactic acidosis.
>Alpha-glucosidase Inhibitors e.g. Acarbose
An alternative approach for overweight patients with type 2 diabetes. Inhibits the enzymes involved in the breakdown of carbohydrates in the intestine. Dietary carbohydrate is poorly absorbed, so post-prandial rise in blood glucose is reduced. Due to undigested starch entering the large intestine, abdominal discomfort, flatulence and diarrhoea can result.
>Thiazolidinediones/Glitazones e.g. Rosiglitazon, Pioglitazone
Reduces insulin resistance by interaction with PPAR-γ. They reduce hepatic glucose formation (synergistic with metformin) and enhance peripheral glucose uptake. However they work best in combination, because as a monotherapy, their glucose-lowering effect is less or similar to other oral agents. Bi-monthly LFT’s recommended for first year of treatment. Tend to cause weight gain and some salt retention.
DIETARY MANAGEMENT
The diet for a diabetic patient is principally the same as that considered healthy for the population as a whole.
Carbohydrates should consist of unrefined carbohydrates rather than simple sugars i.e. foods with a lower glycaemic index. For those on insulin regimes, a knowledge of the carbohydrate component of food is important, and now it is possible to match the amount of carbohydrate in a meal with a dose of short-acting insulin using methods such as DAFNE (Dose Adjustment For Normal Eating). However patient education is very important for this to be possible.
Fatshould be restricted to less than 35% of the total diet with less than 10% being made up of saturated fat and 10-20% of monounsaturated fats.
Protein should only make up 10-15% of the diet and not exceed 1g/kg of body weight.
Salt is the same advice given to the population, under 6g a day. This is reduced to 3 grams a day in a hypertensive diabetic patient.
Alcohol can be consumed in moderation unless there is a coexisting medical problem that requires abstinence. As alcohol suppresses gluconeogenesis, it can precipitate or protract hypoglycaemia, particularly in patients taking insulin or sulphonylureas.
Calories should be tailored to the individual needs of the diabetic patien
An overweight patient is started on a reducing diet (1000-1600 kcal) daily. A lean patient is put on an isocaloric diet. Patients who are underweight because of untreated diabetes require energy supplementation.