Rapid Responses to:

EDITORIALS: Ronald P Stolk Screening for diabetes BMJ 2007; 335: 457-458 [Full text]

Rapid Responses: Submit a response to this article

Rapid Responses published:

Is anxiety induced by screening for cardiovascular risk factors such a bad thing?

Colin White, WF8 1PL   (9 September 2007)

Screening for Diabetes - Much Uncertainty Remains

james m lawrence   (10 September 2007)

EBM or ethical pragmatism

Rupert Gude   (22 September 2007)

Importance of (Targeted) Screening for Diabetes

Mayer Davidson   (29 September 2007)

Is anxiety induced by screening for cardiovascular risk factors such a bad thing? 9 September 2007
Colin White, Consultant Diabetologist Pontefract General Infirmary, WF8 1PL Send response to journal: Re: Is anxiety induced by screening for cardiovascular risk factors such a bad thing?	There is an implicit assumption in the editorial written by Professor Stolk, "Screening for diabetes" and the two accompanying studies by Eborall and colleagues, that anxiety caused by screening for diabetes should be avoided or at least minimised. Eborall and colleagues acknowlege that "qualitative work has shown that patients with screen detected type 2 diabetes tend to think their disease is not serious". That is certainly my experience as a diabetes specialist and a large part of my work is persuading people with type 2 diabetes that it presents a very significant risk to their health and life expectancy and motivating them to adopt a healthy lifestyle and accept a variety of evidence based treatments. It is my duty as a doctor to explain all of this to my patients and to make sure that they understand but there is a difficult line to tread between causing the minor degree of anxiety inevitable in changing behaviour and creating alarm and despondency leading to disengagement. Diabetes aside, there a similar problem in the population wide approach to healthier living, recognition of cardiovascular risk factors and the use of cost effective treatments. Surely, making people worry about all of this is a necessity; isn't that the aim of the graphic warnings on cigarette packets? Competing interests: None declared
Screening for Diabetes - Much Uncertainty Remains 10 September 2007
james m lawrence, Consultant Diabetes and Endocrinology Salisbury Hospital SP2 Send response to journal: Re: Screening for Diabetes - Much Uncertainty Remains	A number of points warrant comment on the editorial by Professor Stolk in this weeks BMJ. Firstly, potential benefits of diabetes screening are multifaceted. Screening to recognise cardiovascular risk is clearly important as this is the major cause of premature death. However, much morbidity is caused by microvascular complications and it remains an important question whether screening for diabetes and potential earlier treatment will reduce the burden of eye, renal and foot complications - something which is brushed over. Secondly, diabetes diagnostic criteria are based on the risk of microvascular complications with a two hour value of >11mmol/l on a glucose tolerance test a threshold at which this risk rises rapidly. Many patients will meet this criteria on an OGTT but will be completely asymptomatic day to day. Isolated raised 2-hour glucose is more common in the elderly - the benefit of identifying such people with earlier treatment with screening is uncertain. Thirdly, if someone has symptoms of a disease and a test is done to make a diagnosis this is not screening but rather a diagnostic test to confirm a clinical suspicion - an important distinction when considering any 'screening' The debate regarding diabetes screening is ongoing - do we need to identify people as having diabetes at all in order to identify those at risk from cardiovascular disease and to modify that risk? Should we just screen with a fasting glucose or does the OGTT add something additional? Should we screen for IGT and does intervention to prevent diabetes reduce long-term complications (both CVD and microvascular)? Answers to these questions will inform the outgoing debate on screening for diabetes - the answers are not yet clear. Competing interests: None declared
EBM or ethical pragmatism 22 September 2007
Rupert Gude, Retired General Practitioner Tavistock, Devon, PL19 9EL Send response to journal: Re: EBM or ethical pragmatism	One guiding principle in my work has been to treat my patients as I would myself or family. 1. Hypertensive patients tend to have metabolic syndrome and screening them for diabetes yields about 1 in 6 tested. 2. Diabetes carries twice to four times the cardiovascular morbidity and mortality of nondiabetics. 3.A significent proportion of type 2 diabetics have microvascular complications at diagnosis especially retinopathy. 4. It is known that early intervention of lifestyle changes like weight loss and increased exercise in impaired fasting glycaemic patients produces a significent reversal of insulin resistance. 5. I know that I, my family and many of my patients need a focus to create meaningful sustained lifestyle changes, ie a diagnosis that concerns us. 6. Neither I nor my 50 , 60 or 70 year old patients have time to wait and see what trials show. I must intervene now or follow Professor Stolks advice to wait for polyuria, polydipsia or even a ketotic admission with its attendant significent mortality. 7.If I was hypertensive or had a waist circumference of greater than 102 cms I would do a fasting blood sugar every 3 years or even persuade my GP to let me have a glucose tolerence test. 8.Therefore on the premise that my patients need to be informed of adverse conditions like early diabetes despite the lack of evidence that early diagnosis will benefit them, I will advise them ( or myself) that it would be prudent to take steps to make significent lifestyle changes. 9.Professor Stolk talks about 'treating asymptomatic people...'. In my practice I inform them of their risks and encourage changes in behaviour. I think it would be unethical to do otherwise. Competing interests: None declared
Importance of (Targeted) Screening for Diabetes 29 September 2007
Mayer Davidson, Professor of Medicine Charles R. Drew University; Los Angeles CA, 90059 Send response to journal: Re: Importance of (Targeted) Screening for Diabetes	It is highly regrettable that an editorial (1) in the British Medical Journal in 2007 can recommend that “we will have to wait until people present with the classic symptoms of thirst and polyuria before screening them” for diabetes. Perhaps the author can be excused because he is an epidemiologist, not a clinician. “Will treating asymptomatic hyperglycemia help prevent cardiovascular disease” is the wrong question. Even though there is an association between glucose levels with cardiovascular disease, even down into the normal range(2,3), there is not good evidence that lowering glycemia will be beneficial in type 2 diabetic patients (4) (although it was helpful in type 1 diabetic patients some 18 years after treatment was initiated [5]). The pertinent question is whether treating asymptomatic hyperglycemia could prevent (or at least lessen) the microvascular complications of diabetes and there the answer is a resounding yes. It is estimated that asymptomatic hyperglycemia has been present for 7 to 10 years before the diagnosis of diabetes (6). This explains the 10%-25% prevalence of microvascular complications when the diagnosis of type 2 diabetes is finally made (7). The distribution of glucose concentrations in most populations is unimodal and there is no clear cut-point that delineates diabetes (8). In 1979 (before the clinical availability of Hb A1c measurements), the National Diabetes Data Group chose a level of glycemia to diagnose diabetes that they believed would cause retinopathy (9). In over 2000 type 1 (10-12) and type 2 (13,14) diabetic patients followed for 6 to 9 years, retinopathy and nephropathy did not develop, or if present at baseline, did not progress, if the mean Hb A1c level were <7.0%. Perhaps then if the rationale for screening for (or possibly diagnosing) diabetes is to identify people who are at risk for the microvascular complications, and since good evidence exists for the attenuation of this risk by lowering glycemia (10,11), using a Hb A1c level of ≥7.0% (8) would fulfill this criteria. Regardless of the method of screening in high risk individuals for diabetes (and there is disagreement concerning how to do this), withholding screening until a person has the symptoms of uncontrolled diabetes would be a great disservice, not only to the individual, but also to society which will have to bear even greater costs for the microvascular complications of diabetes. REFERENCES 1. Stolk RP. Screening for diabetes. Targeted screening causes less stress than mass screening, but there is insufficient evidence to advocate either. BMJ 2007;335:457-8. 2. Coutinho M, Gerstein HC, Wang Y, Yusuf S. The relationship between glucose and incident cardiovascular events. A metaregression analysis of published data from 20 studies of 95,783 individuals followed for 12.4 years. Diabetes Care 1999;22:233-40. 3. Khaw K-T, Wareham N, Luben R, et al. Glycosylated haemoglobin, diabetes and mortality in men in Norfolk cohort of European Prospective Investigation of Cancer and Nutrition (EPIC• Norfolk). BMJ 2001;322:15-8. 4. Huang ES, Meigs JB, Singer DE. The effect of interventions to prevent cardiovascular disease in patients with type 2 diabetes. Am J Med 2001;111:633-42. 5. The Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study Research Group. Intensive diabetes treatment and cardiovascular disease in patients with type1 diabetes. N Engl J Med 2005;353:2643-53. 6. Harris ML, Klein R, Welborn TA, Knuiman MW. Onset of NIDDM at least 4- 7 years before clinical diagnosis. Diabetes Care 1992;15:815-9. 7. Harris MI. Undiagnosed NIDDM: clinical and public health issues. Diabetes Care 1993;16:642-52. 8. Davidson MB. Clinical irrelevance of the current diagnostic criteria for abnormal carbohydrate metabolism in asymptomatic individuals. Curr Opin Endocrinol Diabetes 2005;12:437-43. 9. National Diabetes Data Group. Classification and diagnosis of diabetes mellitus and other categories of glucose intolerance. Diabetes 1979;28:1039-57 10. The Diabetes Control and Complications Trial Research Group. The relationship of glycemic exposure (HbA1c) to the risk of development and progression of retinopathy in the diabetes control and complications trial. Diabetes 1995;44:968-83. 11. Ohkubo Y, Kishikawa H, Araki E, et al. Intensive insulin therapy prevents the progression of diabetic microvascular complications in Japanese patients with non-insulin•dependent diabetes mellitus: a randomized prospective 6-year study. Diabetes Res Clin Pract 1995;28:103-7. 12. Krolewski AS, Laffel LMB, Krolewski M, et al. Glycosylated hemoglobin and the risk of microalbuminuria in patients with insulin-dependent diabetes mellitus. N Engl J Med 1995;332:1251-5. 13. Tanaka Y, Atsumi Y, Matsuoka K, et al. Role of glycemic control and blood pressure in the development and progression of nephropathy in elderly Japanese NIDDM patients. Diabetes Care 1998;21 :116-20. 14. Warram JH, Scott U, Hanna LS, et al. Progression of microalbuminuria to proteinuria in type 1 diabetes: nonlinear relationship with hyperglycemia. Diabetes 2000;49:94-100. Competing interests: None declared Dr. Davidson is supported by NIH grant U54_RR014616 Competing interests: None declared