Hepatogenous diabetes differs from type 2 diabetes in that there is less often a positive family history and that the cardiovascular and retinopathic risk is low. The prognosis of cirrhotic patients with diabetes is more likely to be negatively affected by the underlying hepatic disease and its complications than by the diabetes. Antihyperglycemic treatment of hepatogenous diabetes should always be carefully weighed up in each individual case.

In people with type 2 diabetes, glimepiride was associated with fewer episodes of severe hypoglycaemia than glibenclamide in routine clinical use. However, severe hypoglycaemia did occur with glimepiride and may be minimised if treatment targets are determined on an individual basis.

Metformin is an effective anti-hyperglycaemic and cardioprotective agent, but a long list of contraindications precludes millions of patients with type 2 diabetes from using it. This is largely due to the historical experience of lactic acidosis with phenformin, despite the fact that metformin does not predispose to this when compared with other therapies. Contraindications such as old age, renal impairment and cardiac insufficiency are increasingly disregarded in clinical practice, yet there is no evidence that the incidence of lactic acidosis has changed. Metformin has been shown to improve metabolic control without causing lactic acidosis in elderly patients with multiple comorbidities, including explicit contraindications, and its use in patients with type 2 diabetes over the age of 70 with mild renal impairment did not produce a clinically relevant increase in plasma lactate. There is no correlation between levels of metformin and lactate in patients with lactic acidosis, and its prognosis is mainly related to the causal hypoxic underlying disease and comorbidities. These findings raise doubts about the pathogenetic significance of metformin in lactic acidosis. We propose that advanced age per se, mild renal impairment and compensated heart failure can no longer be upheld as contraindications for metformin. A clear re-definition of contraindications to metformin will enable more physicians to prescribe within guidelines.

In patients with Type 2 diabetes, the appropriate intensity of glucose control is determined by age, life expectancy, and the presence of concomitant disease. Geriatric patients are especially susceptible to hypoglycaemia and therefore particular care should be taken in this group characterized by polypharmacy, renal or hepatic dysfunction, cardiovascular multimorbidity and malnutrition. As hypoglycaemia is a significant cause of morbidity and mortality, treatment regimens for diabetes should minimize the occurrence of hypoglycaemic episodes and be tailored to the patient's individual needs. The pharmacological options for treating Type 2 diabetes have increased considerably and the risk of hypoglycaemia of the currently available drugs varies considerably. Metformin, thiazolidinediones, and acarbose, oral antidiabetic drugs that decrease insulin resistance or postprandial glucose absorption, are associated with a low risk of hypoglycaemia. These drugs can also be used effectively in various combination regimens; however, by improving insulin sensitivity, combinations of metformin and thiolidinediones with sulphonylureas or meglitinides may considerably increase the risk of hypoglycaemia. On account of its complex pharmacoprofile glibenclamide is a problematic substance carrying a high risk of hypoglycaemia. There are limited preliminary data indicating that, under routine conditions, glimepiride may be associated with a lower risk of hypoglycaemia than glibenclamide and is no more likely to cause hypoglycaemia than other shorter-acting agents such as gliclazide and glipizide. Nateglinide and repaglinide as short-acting insulin secretagogues may be associated with a reduced risk of hypoglycaemia compared with glibenclamide, in particular when dosed flexibly. Repaglinide might be beneficial in individuals with renal impairment.

Despite the considerable risk of lactic acidosis in the majority of patients, no cases were observed.

AimsThe genetically polymorphic cytochrome P450 (CYP) enzyme CYP2C9 metabolizes most sulphonylurea oral hypoglycaemic agents. The aim of this study was to test the hypothesis that individuals with genotypes predicting low CYP2C9 activity may be at a higher risk of severe drug-associated hypoglycaemia. MethodsIn a case-control study, 20 diabetic patients admitted to the emergency department with severe hypoglycaemia during sulphonylurea drug treatment were compared with a control group of 337 patients with type 2 diabetes but without a history of severe hypoglycaemia. A large sample of 1988 healthy Caucasian subjects served as a second control group. ResultsThe CYP2C9 genotypes * 3/ * 3 and *2/*3 that are predictive of low enzyme activity were more common in the hypoglycaemic group than in the comparison groups (10% vs < 2%, respectively: odds ratio 5.2; 95% confidence interval 1.01, 27). Furthermore, the diabetic patient group with severe hypoglycaemia exhibited lower body mass indexes, higher rates of renal failure, were older compared with the diabetic group without severe hypoglycaemia, and were being treated with higher doses of glibenclamide. ConclusionsThese findings suggest that among other factors, individuals with genetically determined low CYP2C9 activity are at an increased risk of sulphonylurea-associated severe hypoglycaemia. Thus, genotyping might be a tool for the better prediction of adverse effects caused by oral hypoglycaemic agents.

In elderly, multimorbid patients approaching the insulin-deficient end of the spectrum of type 2 diabetes the risk of developing SH increases considerably, nearing that in patients with type 1 diabetes. In order to avoid SH in geriatric patients, the treatment targets should be defined critically, taking into account individual quality of life and life expectancy. Hypoglycaemia unawareness is a major risk factor for SH in type 1 diabetes.

Uncritical prescription of sulfonylureas neglecting crucial contraindications - particularly renal insufficiency - and deficiencies of diabetes care contributed substantially to the risk of SH in the mainly geriatric patients. There is a need for alternative therapeutic concepts that minimize the risk of hypoglycemia in geriatric patients with T2DM.