This group addresses appropriate issues around blood glucose monitoring in relation to the Drug Tariff, NHS Supply Chain, patient safety and government policy regarding diabetes.
The diabetes working party aims to engage constructively with government, NHS and patient groups to the benefit of industry and the diabetes community.
What is diabetes?
Diabetes mellitus is due to an absolute or relative deficiency of insulin, a hormone produced in the pancreas. There are two main types of diabetes.
Type 1- Insulin Dependent Diabetes Mellitus (IDDM)
Type 2 - Non-Insulin Dependent Diabetes Mellitus (NIDDM)
Approximately 90% of people with diabetes have Type 2.
Type I manifests itself in the form of serious acute illness and usually becomes apparent before the age of 40. There is absolute insulin deficiency and life-long injections of insulin are essential.
Type 2 is usually a disease of older people and is caused by alteration of the body's response to insulin. Although treatment with insulin may be needed, Type 2 diabetes can often be controlled by diet and exercise, sometimes combined with tablets which lower the level of glucose in the blood.
The onset of Type 2 is gradual and may be preceded by a long period of impaired glucose tolerance (IGT). Consequently the identification of IGT in an individual implies a high risk of developing clinical diabetes. Impaired fasting glycaemia (IFG), where the fasting blood glucose is higher than it should be, has been found to be a risk factor for the development of diabetes and/or cardiovascular disease.
There are other less common types if diabetes, the most important of which, in the UK, is gestational diabetes which occurs in pregnancy.
Who does it affect?
Approximately 3% of the UK adult population (1.4 million people) have been diagnosed as having diabetes. Estimates suggest that a further one million people have diabetes but are not aware of it. The statistical risk of developing diabetes in the UK is one person in every 10, with some ethnic groups showing even higher incidence rates.
Recent research in the UK has found that the incidence of Type 1 in children under five doubled between 1985 and 1995, whilst cases of diabetes in children under 15 years have seen an overall increase of about 4% each year.
High risk groups for Type 2 diabetes
Older age (over 40)
Close family member affected
Asian or African/Caribbean origin
Overweight
Physical inactivity
History of gestational diabetes
Evidence of impaired glucose tolerance
Classical Symptoms
Thirst
Increased urine volume
Weight loss
Lack of energy
Irritability
Genital itching
Infections
What are the symptoms?
Type 2 is often difficult to recognise and many patients have no or only mild symptoms. Consequently it is not sufficient to rely on classical symptoms especially in high risk groups. Measurement of blood glucose levels is the only definitive test.
What are the complications?
Diabetes is the single biggest cause of blindness in the working population in the UK.
The risk of coronary heart disease is increased 2-3 fold in men with diabetes and 4-5 fold in women. The risk of a stroke is increased 2-3 fold.
Half of all lower limb amputations are a consequence of diabetes.
40% of people awaiting renal transplants have diabetes.
Cost to the NHS
The latest figures from Diabetes Uk (British Diabetic Association) indicate that the annual cost of all diabetes to UK NHS hospitals exceeds £2 billion. Whilst this represents approximately 8% of the total NHS budget, it is an underestimate of the true cost of diabetes as it does not include the cost of primary care nor the cost of care for conditions not reported as being diabetes related.
What further action is needed?
Early treatment - Earlier diagnosis, with screening of high risk groups such as the overweight, inactive elderly, those with a family history of diabetes and some ethnic groups. Early treatment is important as effective management can help to prevent complications and delay progression of the disease.
Control of blood glucose – Achieving good control of blood glucose is important. The Diabetes Control and Complications Trial (DCCT) report clearly showed that intensive insulin treatment to control blood glucose, more than halved the risk of microvascular complications in Type 1 diabetes. The United Kingdom Prospective Diabetes Study (UKPDS) showed similar findings for Type 2.
Patient education - Regular health checks to detect complications. Closer links between specialists in hospitals and local family doctors to monitor patient care jointly. Provision of dietitians, chiropodists and health educators in the specialist diabetes teams.
The role of diagnostic (IVD) testing
Blood Glucose test
This can be done by the doctor, either in his clinic or by sending a blood sample to the hospital laboratory. There are also a number of easy-to-use home testing products, which the individual can use to test their own blood glucose level. Many people with diabetes test their own blood glucose level two to four times a day. Blood glucose testing can help a diabetic understand how food, physical activity, and medicines affect their blood glucose level. Testing can help make day-to-day choices about how to balance these things. It can also tell when the glucose level is too low or too high so that corrective action can be taken.
The diagnosis of dabetes should always be made on the basis of glucose measurement performed in a clinical laboratory.
HbAIc, also called Haemoglobin A1c or Glycated Haemoglobin test
Haemoglobin is the red pigment in the millions of red cells in the blood that carry the oxygen around the body. Some of the glucose in the blood sticks to the haemoglobin, (called glycation of the haemoglobin) and stays there until each red cell naturally ends it's life and is replaced by a new one. If someone has a high blood glucose level, more glucose will stick to the haemoglobin. As the red blood cells live for several weeks, measuring the amount of haemoglobin that has glucose attached to it, indicates the general level of blood glucose over that period of time. This laboratory test helps doctors to have a long term view of how well a person is controlling their glucose levels, whereas a blood glucose test only tells them what the level is at the moment the test is done.
Urinary Glucose test (also known as urine sugar test)
Sometimes urine tests are used to monitor the level of blood glucose. The kidneys filter our blood and produce urine, to get rid of waste chemicals the body makes. If the blood sugar rises above a certain level, the kidneys 'overflow’ with glucose and some escapes, and can be detected by diagnostic tests. It just happens that the blood glucose level at which the kidneys start to let some go into the urine (known as the renal threshold), is close to the level that diabetics who control their blood glucose levels by diet do not wish to exceed, so it can be a useful test. It cannot, of course, indicate if the blood glucose level is too low. Measuring glucose in the blood is always preferable to relying on urine testing.
Urine test for 'microalbuminuria'.
This test is carried out in the hospital laboratory and measures the tiny amounts of one of the body's proteins, which can leak into the urine and indicates the way the kidneys are coping with the effects of diabetes. The better the control of the blood glucose level in the long term, the less likely that the kidneys will let the protein escape into the urine.
Summary of testing
From this we see that the tests for blood glucose (blood sugar) and urine glucose (urine sugar) tell us about the glucose level at the time the test is done. On the other hand, the test for Glycated Haemoglobin (HbA1c) indicates the level of blood glucose control over a period of weeks, and the urinary microalbumin test indicates the long term effects of blood glucose levels on the kidneys. This is why the doctor and the scientists in the hospital laboratory will use all of them at different times to better understand what the glucose levels are and have been, because all the evidence is that the better the control of the blood glucose levels, the less likely the individual is to suffer ill health as a consequence of Diabetes.
References
(1) The T2ARDIS (Type 2 diabetes: Accounting for a Major Resource Demand in Society) survey was carried out by the BDA, the King's Fund, the Economists Advisory Group and SmithKline Beecham Pharmaceuticals, UK. The survey builds on the work of the UKPDS (UK Prospective Diabetes Study) and the CODE-2 (Cost of Diabetes in Europe - Type 2) studies and emphasises the economic burden placed on the individual and their carers.
(2) New.Eng.J.Med. (1993) 329: 977-986 (DCCT)
(3) UKPDS (UK Prospective Diabetes Study)
(4) "Testing Times" Audit Commission Report April 2000
BMJ 2001;322:377-378 ( 17 February )
Editorial
Type 2 diabetes in children
Exemplifies the growing problem of chronic diseases Type 2 diabetes mellitus in children is an emotionally charged issue and an emerging public health problem. 1 2 Until recently most children with diabetes mellitus had type 1, one of the most common3 and increasingly prevalent4 chronic diseases in children. Increasingly, however, type 2 diabetes is being reported in children from the United States, Canada, Japan, Hong Kong, Australia, New Zealand, Libya, and Bangladesh.5 The prevalence of type 2 diabetes in children ranges from 4.1 per 1000 12-19 year olds in the US to 50.9 per 1000 15-19 year old Pima Indians of Arizona. 1 2 Between 8% and 45% of recently diagnosed cases of diabetes among children and adolescents in the United States is type 2, and the magnitude of this disease may be underestimated. 1 2 The prevalence of the disease is on the rise in North America, and its incidence almost doubled in Japan between 1976-80 and 1991-5from 7.3 to 13.9 per 100 000 junior high school children.5 These trends coincide with the rising prevalence of overweight and physical inactivity world wide. 5 6-8
Among US children the mean age at diagnosis of type 2 diabetes is between 12 and 14 years, corresponding with puberty; the disease affects girls more than boys, predominantly people of non-European origin, and is associated with obesity, physical inactivity, a family history of type 2 diabetes, exposure to diabetes in utero, and signs of insulin resistance. 1 2 At diagnosis the affected child may present with weight loss, ketosis, and acidosis. 1 2 Insulin and C peptide levels are often raised and antibodies absent, which may help differentiate type 1 from type 2 diabetes, but insulin secretion may well be blunted at diagnosis.1 Haemoglobin A1c levels may range from 10% to 13%, and a sizeable proportion of patients have hypertension, hypertriglyceridemia, albuminuria, sleep apnoea, and depression,2 and these factors may worsen over time.9 However, treatment protocols vary considerably, and several of the drugs used for glycaemic, blood pressure, and lipid control are not approved for use in children. 1 2
To respond to this emerging problem, the American Diabetes Association and the American Academy of Pediatrics issued a joint consensus statement, and the Committee for Native American Child Health is developing treatment guidelines based on expert opinion. The National Institutes of Health and the Centers for Disease Control and Prevention have each embarked on new research programmes to improve gaps in our knowledge. So, what do we need to know and do?
Firstly, we need to develop case definition(s) that will differentiate between types of diabetes in children, and will be suitable for estimating the magnitude of the disease in populations 2 and for clinical diagnosis.1 Case definitions for public health surveillance and clinical purposes should involve simple low cost tests, an issue of importance to poor countries and communities.
Secondly, epidemiological data on the magnitude of the problem, its secular trends, and follow up of incident cases are needed for several at risk populations. 1 2 Limited data are available in selected populations such as the American Indians, but few data exist for several parts of the world where the disease is prevalent.
Thirdly, adult studies have shown efficacious interventions for type 2 diabetes, but their safety and efficacy in children is not known. Also needed are well coordinated, multicentre trials testing the feasibility of multiple risk factor reduction in children and its benefits for practical health outcomes, such as the early stages of vascular disease.
Fourthly, despite efficacious treatments, the quality of care for adults with type 2 diabetes remains suboptimal.10 This situation is likely to be worse for children and adolescents 1 2 because this is a new problem for clinicians; adolescents may be particularly reluctant to make behavioural changes, manage their disease, and accept follow up; and access to health care may be inadequate. Carefully conducted studies of quality of care and of potential interventions among children are needed.
Finally, type 2 diabetes in children offers some unique opportunities to understand the causes of the disease and of insulin resistance 1 2 and to plan primary prevention. Early onset of diabetes may be due largely to genetic factors, which would mean that identification of genetic mechanisms might be profitably pursued in children. On the other hand, all societies worldwide are undergoing changes that are leading to major behavioural and environmental modifications. Among adults type 2 diabetes is highly related to behavioural and environmental factors 11; the effect of these factors on children needs to be understood.
The emergence of the disease in young people embodies the growing problem of chronic diseases worldwide and their extension to youth. The rising prevalence of obesity and type 2 diabetes in children is also the unforeseen consequence of worldwide industrialisation. To fight type 2 diabetes as a paediatric disease will require use of recent medical advances but will also require understanding and questioning the unwanted changes from industrialisation. Gaps still exist in our knowledge of disease classification, magnitude and trends, causes, treatment efficacy and safety, quality of care, and behavioural and environmental factors. Thus, we need worldwide cooperation and collaboration to develop studies in each of these areas using standardised protocols. In the meantime primary care workers should watch out for type 2 diabetes in children.
Anne Fagot-Campagna, medical epidemiologist.
K M Venkat Narayan, chief, diabetes epidemiology section (kav4@cdc.gov)
Giuseppina Imperatore, medical epidemiologist.
Division of Diabetes Translation, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Mailstop K-68, Atlanta, GA 30341, USA
1. American Diabetes Association. Type 2 diabetes in children and adolescents. Diabetes Care 2000; 23: 381-389[Medline].
2. Fagot-Campagna A, Pettitt DJ, Engelgau MM, Ríos Burrows N, Geiss LS, Valdez R, et al. Type 2 diabetes among North American children and adolescents: an epidemiological review and a public health perspective. J Pediatr 2000; 136: 664-672[Medline].
3. LaPorte RE, Matsushima M, Chang YF. Prevalence and incidence of insulin-dependent diabetes. In: Harris MI, Cowie CC, Stern MP, Boyko EJ, Reiher GE, Bennett PH, eds. Diabetes in America. 2nd ed. Washington, DC: National Institutes of Health, NIDDK, 1995:37-46.
4. Onkamo P, Väänänen S, Karnoven M, Tuomilehto J. Worldwide increase in incidence of type 1 diabetes: the analysis of the data on published incidence trends. Diabetologia 1999; 42: 1395-1403[Medline].
5. Fagot-Campagna A. Emergence of type 2 diabetes mellitus in children: the epidemiological evidence. J Pediatr Endocrinol Metabol (in press).
6. Troiano RP, Flegal KM, Kuczmarski RJ, Campbell SM, Johnson CL. Overweight prevalence and trends for children and adolescents. The National Health and Nutrition Examination Surveys, 1963 to 1991. Arch Pediatr Adolesc Med 1995; 149: 1085-1091[Medline].
7. Ingram M. British children are getting fatter and many are dangerously overweight. What can be done? Times 2000;21 Jul.
8. Bursaux E. Le nombre d'enfants obèses a doublé au cours des dix dernières années. Le Monde 2000;21 Jun.
9. Fagot-Campagna A, Knowler WC, Pettitt DJ. Type 2 diabetes in Pima Indian children: cardiovascular risk factors at diagnosis and 10 years later. Diabetes 1998; 47(suppl 1): A155.
10. Narayan KMV, Gregg EW, Fagot-Campagna A, Engelgau MM, Vinicor F. DiabetesA common, serious, costly, and potentially preventable public health problem. Diab Res Clin Pract 2000; 50 (suppl 2): 77-84.
11. Rewers M, Hamman RF. Risk factors for non-insulin-dependent diabetes. In: Harris MI, Cowie CC, Stern MP, Boyko EJ, Reiher GE, Bennett PH, eds. Diabetes in America. 2nd ed. Washington, DC: National Institutes of Health, NIDDK, 1995:179-220.