The growing global burden of diabetes

While local figures are not current and at best nebulous, experts estimate around 3-million South Africans have diabetes, of which approximately 95% are type 2 diabetes. These figures are further underestimated by the fact that many cases go undiagnosed.

While the prevalence of diabetes is increasing throughout the world, the developing countries will bear the greatest burden of this disease. For example, the number of people with diabetes will increase by about 90% in Africa by 2025. The International Diabetes Federation (IDF) figures report that at least 194-million people worldwide suffer from diabetes, with the incidence of the disease rapidly increasing. It is estimated that by the year 2025, this number will double.

An increasing trend towards urbanisation, with adoption of sedentary lifestyle and high-energy diets, is the main driving force for diabetes in the developing world. In South Africa about 42% of the female population and 15 to 20% of the male population are overweight. This, coupled with late diagnosis (on average patients live with the disease for seven-years prior to diagnosis) makes a case for closer examination of the disease, its identification and early aggressive intervention strategies to reduce the burden of morbidity and mortality.

Prof Charles Reasner, a Professor of Medicine at the University of Texas Health Sciences Centre and Medical Director at the Texas Diabetes Institute, one of the largest diabetes centres in the USA, who delivered lectures around the country in May, says that type 2 diabetes confers the same adverse prognosis as a prior myocardial infarction.

“Data from a population-based study in Finland involving 1 373 type two diabetic patients and 1 059 non-diabetic control subjects were used to establish the influence of type 2 diabetes on prognosis. The average follow-up was seven-years. The mortality rate in non-diabetic subjects without a history of myocardial infarction was lowest, and the mortality rate among diabetic subjects with a previous myocardial infarction was highest, as would be expected1,” says Reasner. “However these data show that developing diabetes, or having previously had a myocardial infarction, confers the same risk of a subsequent myocardial infarction.”

He added that the effects of cardiovascular risk factors associated with the metabolic syndrome - which include insulin resistance, hyperinsilinaemia, obesity, dyslipidaemia, glucose intolerance, type 2 diabetes and hypertension - on clinical outcomes is magnified in type 2 diabetic patients compared with non-diabetic subjects.

Data from the UK Prospective Diabetes Study main analysis predict that for every 100 patients diagnosed at age 55-years of age, 27 will suffer a myocardial infarction, 10 will have a stroke, 23 will develop diabetic retinopathy (the leading cause of blindness in western populations), and 28 will die from a cause related to their diabetes.

It is well established that patients diagnosed with type two diabetes in their middle age have most to lose, with a potential loss of five-to-seven years of life, due to long-term complications of the disease. “Prevention of complications is key, as they bring unacceptable burden in costs, complications including death. This requires a multifactorial approach where factors such as obesity, hyperglycaemia, microalbimunuria, dyslipidaemia and hypertension, are effectively addressed through lifestyle and pharmacological intervention to reduce the risks,” says Glucovance product manager Taki Radzilani.

“The hyperglycaemia associated with type 2 diabetes is progressive and is driven primarily by the dual endocrine defects of type 2 diabetes i.e. insulin resistance and impaired beta-cell function. This, coupled with the fact that treatment based on diet or oral monotherapy is usually only effective for a limited time, adequately demonstrates the need for ongoing tight disease management strategies, of this complex disease that burdens so many,” adds Radzilani.

The most recent guidelines from the ADA/EASD advocates early intensification of therapy once the goal glycaemic targets are exceeded. Glucovance®, a fixed-combination drug therapy - is a rational choice when more effective glycaemic control is required post monotherapy failure.

Radzilani goes on to say that as with any oral antidiabetic agent, therapy with Glucovance should be initiated using lower dosages, intensifying therapy every one-to-two weeks depending on patient response and tolerability.

Commenting on Merck's anti-diabetic combination oral therapy, Reasner says: “Patients who present with HbA1c in excess of 9% are unlikely to reach goal glycaemia with any monotherapy. Glucovance addresses both components of the dual endocrine defect of type 2 diabetes. Well-designed clinical trials have shown that Glucovance is effective in patients with hyperglycaemia inadequately controlled by diet and exercise or prior oral monotherapy. It's effective irrespective of the severity of hyperglycaemia, age or body mass index of patients prior to treatment5. A further double-blind randomised trial showed that Glucovance was more effective than the free combination of metformin and sulphonylurea given separately.”

“Poor compliance with treatment is common among type 2 diabetic patients. The potential for simplification of oral antidiabetic regimes with Glucovance helps to support good compliance with therapy.” concludes Reasner.

Diabetes is in the top 10, and perhaps the top five, of the most significant diseases in the developed world, and is gaining in significance there and elsewhere. For further information mail: Taki Radzilani on .