Diabetes – what needs to be done

During the recent NIPC conference, Prof Tim O’Brien, consultant endocrinologist and dean of the College of Medicine, Nursing and Health Sciences at NUI Galway, highlighted the hidden epidemic that is diabetes, which he stressed is a vascular disease. He pointed out that the WHO has pinpointed diabetes as the greatest threat to public health in the next century, with type two diabetes being the main driver of the increased incidence, accounting for 90% of all cases.

In Ireland, nearly one in 10 adults has diabetes and it costs the State E580 million per annum to deal with it. These costs are projected to rise significantly in future years, Prof O’Brien told the NIPC conference in Galway.

He said there is evidence that diabetes and its complications can be prevented, but this requires a systems-wide approach. The Finnish Diabetes Prevention study of 2001, among other research, has shown how prevention strategies can have an effect. In the Finnish trial, the risk of diabetes was reduced by 58% in the intervention group, where intervention included counselling on diet and physical activity.

Lifestyle intervention

In the US Diabetes Prevention Programme, lifestyle intervention reduced the incidence of diabetes by 58% and taking metformin reduced it by 31%. The message was that lifestyle and dietary intervention did have a major role in preventing diabetes, Prof O’Brien told the meeting.

On testing for diabetes in asymptomatic patients, he said, key criteria included obesity/overweight (BMI over 25) with one additional risk factor such (eg. CVD, physical inactivity), or age over 45. The type of testing to be done can be either HbA1c (probably the fastest and simplest test), fasting plasma glucose, or a 75g two-hour glucose tolerance test. If the test is normal, it should be carried out three years later.

Patients designated as ‘prediabetes’ – those at increased risk of developing the condition – are those who would have a fasting glucose level of 5.6 to 6.9; a two-hour glucose tolerance test where the two-hour values are between 7.8 and 11.0 and a HbA1c of 39-46mmol/mol.

Diagnosis of diabetes mellitus is where there is a HbA1c of 48mmol/mol or more; a fasting glucose level greater than seven or a random glucose of more than 11 plus symptoms and a two-hour oral glucose tolerance test of over 11.

For the prevention or delay of type 2 diabetes, patients with impaired glucose tolerance or impaired fasting glucose, or A1c 39-46mmol should be referred to an ongoing support programme. A weight loss of 7% of body weight should be targeted with at least 150 minutes per week of moderate physical exercise recommended.

Metformin can be considered where there is IGT, IFG or A1c of 39-46. Those with prediabetes require yearly monitoring and modifiable risk factors for CVD should be screened for and treated. Prof O’Brien said follow-up counselling was important.

On prevention of diabetes complications once diabetes develops, he said there was now substantial evidence that these complications can be prevented, both microvascular and cardiovascular.

There is a ‘trinity’ of factors involved in preventing diabetes complications – glucose, blood pressure and lipid control,  and this is best achieved through intensive lifestyle management involving exercise, weight control and smoking cessation. Added to this is the use of pharmacotherapy.

Prof O‘Brien pointed out that recent information indicated that over-aggressive pharmacological treatment to reach glycaemic targets can be harmful in type 2 patients, and therefore it is now being recommended that targets be individualised. BP targets with pharmacotherapy had recently been raised to 140/80 from 130/80 following recent research.

Medication

He said in practice, while lifestyle, diet and exercise are key management components, 80% of diabetes patients will require a minimum of three medications for control of hypertension in diabetes.

It is recommended that everybody with diabetes who has overt CAD or patients over 40 with at least one other risk factor should be on a statin regardless of their LDL.

Prof O’Brien said primary prevention in diabetes can be achieved through lifestyle interventions. In terms of finding the unrecognised diabetes patients, this can be done through screening and diagnosis. However, this will push these patients into the recognised diabetes cohort and enter a healthcare system already creaking at the seams.

Prof O’Brien said therefore, in order to tackle the increasing burden of diabetes, a concerted effort is required to move the current model of care to one where we will prevent diabetes taking place, where more cases of diabetes are recognised, and where patients with the condition will be properly cared for.

However, that model will not be achieved by any one stakeholder in the health service and the concerted effort would have to include primary/community care; public health; secondary care; action from the government/HSE through clinical care programmes; academia and industry and charities (Croi/Diabetes Ireland, etc) and philanthropy.