Evidence Limited for Screening Most Adults for Type 2 Diabetes – You have got to be kidding!!

Evidence Limited for Screening Most Adults for Type 2 Diabetes – You have got to be kidding!!

The US Preventive Services Task Force (USPSTF) has issued a statement that limited evidence exists to recommend screening adults for type 2 diabetes but that screening may be helpful in those with hypertension, according to a report published in the June 3 issue of the Annals of Internal Medicine.

"More than 19 million Americans are affected by type 2 diabetes mellitus, which is undiagnosed in one third of these persons," write Susan L. Norris, MD, MPH, from the Oregon Evidence-based Practice Center of the Oregon Health & Science University and Portland Veterans Administration Medical Center, and colleagues. "In addition, it is estimated that more than 54 million adults have prediabetes. Debate continues over the benefits and harms of screening and then treating adults who have asymptomatic diabetes or prediabetes."

The goal of this statement was to update the 2003 USPSTF review of the evidence with regard to potential benefits and risks of screening adults for type 2 diabetes and prediabetes in the primary care setting.

The reviewers searched MEDLINE and the Cochrane Library for relevant studies and systematic reviews published in English between March 2001 and July 2007 and included trials and observational studies that evaluated the effectiveness and adverse effects of screening interventions. The efficacy of treatments of diabetes and prediabetes were evaluated with randomized controlled trials of patients with disease for 1 year or less. Trials comparing outcomes among patients with and without diabetes were also reviewed.

The reviewers abstracted relevant data in duplicate using a standardized template, and they synthesized data in a qualitative fashion. A random-effects meta-analysis determined the effects of interventions in prediabetes on the incidence of diabetes.
Limitations of the review were that most of the evidence concerning diabetes treatment came from subgroup analyses vs primary trial data and that participants in intensive lifestyle interventions for prediabetes may not be representative of general prediabetic populations.

"Direct evidence is lacking on the health benefits of detecting type 2 diabetes by either targeted or mass screening, and indirect evidence also fails to demonstrate health benefits for screening general populations," the review authors write. "Persons with hypertension probably benefit from screening, because blood pressure targets for persons with diabetes are lower than those for persons without diabetes. Intensive lifestyle and pharmacotherapeutic interventions reduce the progression of prediabetes to diabetes, but few data examine the effect of these interventions on long-term health outcomes."
Specific recommendations of the USPSTF with regard to screening for type 2 diabetes mellitus in adults are as follows:

• Because high blood pressure is a recognized risk factor for cardiovascular complications in people with type 2 diabetes mellitus, blood pressure should be measured.
• Asymptomatic adults with no symptoms of type 2 diabetes mellitus or evidence of possible complications of diabetes but with sustained blood pressure greater than 135/80 mm Hg (treated or untreated) should be screened for type 2 diabetes mellitus (level of evidence, B).
• For asymptomatic adults with sustained blood pressure of 135/80 mm Hg or lower, no recommendation has been made regarding screening for type 2 diabetes mellitus (grade: I; insufficient evidence).
• Screening may be considered on an individual basis when blood pressure is 135/80 mm Hg and when knowledge of diabetes status would facilitate decisions with regard to preventive strategies for coronary heart disease, including consideration of lipid lowering.
• To screen for diabetes, 3 tests that have been used are fasting plasma glucose, 2-hour postload plasma, and hemoglobin A1c.
• The American Diabetes Association recommends screening with fasting plasma glucose, defining diabetes as a fasting plasma glucose level of 126 mg/dL or greater, and confirming an abnormal result with a repeated screening test on a separate day.
• Although the optimal screening interval is still unknown, expert opinion from the American Diabetes Association recommends a screening interval of every 3 years.
• Information about the 10-year risk for coronary heart disease must be considered when deciding if screening would be helpful on an individual basis. As a hypothetical example, if the risk for coronary heart disease without diabetes was 17% and the risk with diabetes was more than 20%, screening for diabetes would be helpful because diabetes status would determine lipid treatment. In contrast, if the risk without diabetes was 10% and the risk with diabetes was 15%, screening would not influence the decision to use lipid-lowering treatment, and it would not be indicated.

"Further research is needed to define the benefits and harms of screening average-risk individuals for type 2 diabetes," the review authors write. "We must learn whether early, aggressive glycemic control in persons with diabetes produces improvements in clinical outcomes after many years of follow-up. . . . Further work is also needed to examine the effect of screening and diagnosis on patient self-efficacy, motivation for lifestyle change, and the potential psychological effects of labeling."

"No direct evidence clearly determines whether screening asymptomatic individuals for diabetes or prediabetes alters health outcomes," the authors of the statement conclude. "Evidence shows that persons with diabetes benefit from control of blood pressure and lipid levels, but studies have not included persons with screening-detected diabetes. Persons with hypertension and type 2 diabetes benefit from lower blood pressure targets than persons with hypertension but without diabetes."
Ann Intern Med. 2008;148:853-854, 855-868.

Clinical Context

Nearly 10% of US adults have diabetes mellitus, and one third of these individuals have not been diagnosed with diabetes. Twenty-six percent of adults have impaired fasting glucose levels or impaired glucose tolerance. These patients with prediabetes have been demonstrated to have an increased risk for macrovascular complications vs adults without impaired fasting glucose levels or impaired glucose tolerance, and the average preclinical phase of diabetes has been estimated to last 10 to 12 years.

Despite these factors, a recommendation from the USPSTF in 2003 concluded that there was insufficient evidence to recommend for or against routine screening for type 2 diabetes in asymptomatic adults. The current review updates these recommendations.

Publishers Comments:
Studies like this just MAKE ME MAD!

Whether it is a study that says it is not cost effective to have Type 2 diabetics on oral drugs not monitor their blood sugars or it is not cost effective to screen for prediabetes, or even diabetes, it just makes me mad.

If we can spend 600 Billion dollars to improve our financial institutions, we can certainly spend 10 dollars for an A1c test for every person who is overweight to find pre-diabetes and diabetes and give them the option to improve their quality of life.

If we just don’t pay one CEO his golden parachute, we would have the money to test every person in this country who is over-weight with a OGTT or A1c test.

What is more important, your financial health or quality of life?  What would you spend to save your eye sight, or your kidneys?  How much are they worth?

If you had to decide, whether to have an extra 10,000 dollars in the bank or live 10 years longer, prevent a debilating stroke and be healthy, which would you choose?

If you had to decide whether to have an extra 100,000 dollars in the bank or not have to live in a nursing home for the last 10 years of your life, which would you choose?

How much is it worth to walk down the aisle with your granddaughter at her wedding?

People have right to know if they are at risk and it is their decision to make life-style changes to improve their chances for a better quality of life, once they know the facts and have been educated!.

WAKE-UP AMERICA!

In the Epic-Norfolk study they looked at people with A1c’s of 5% and compared them to people with A1c’s of 6% and found that people with an A1c of 6%, had a 28% increase in cardio-vascular death, regardless of diabetes!  And we are still trying to get people to an A1c of 7%?

In a recent study on the people who were in the UKPDS and the DCCT trials study they found that treating patients aggressively and early protected them years later.

We know that treating patients early will save their beta-cells so they can work more effectively and even possibly allow them to regenerate themselves,  so they can live a more normal life.

So tell me why we should not invest in our health?

Last week, I sat with 10 newly diagnosed patients with diabetes and prediabetes and spent 2 hours of my time to educate them.  I taught them how to read food labels, count carbs, why they should monitor their blood sugars after eating and how to monitor their physical activity with the use of a pedometer, which I provided. At the end of the program, they thanked me and said that it was the best program they have ever attended and that they would make the changes to improve their quality of life, that they now had the correct information on how to control their diabetes and prevent the complications.

We can make a difference.

WAKE-UP AMERICA!  Before it is too late.

Steve Freed, Publisher: www.diabetesincontrol.com

Pres of the Chicago Chapter of the American Association of Diabetes Educators

Additional Research Making the point, we need to find people early in the progression of diabetes and we need to treat aggressively and as early as possible:

In the Diabetes Prevention Program (DPP), even in patients with pre-diabetes, diabetic retinopathy was noted in 8% of patients.3,8,9 Neuropathy has also been noted in patients with pre-diabetes. In population-based studies, it is estimated that peripheral neuropathy is seen in up to 14% of the general population. However, a number of studies have shown that the prevalence of peripheral neuropathy is much higher in those with pre-diabetes. For example, in a group of 187 sequential patients with idiopathic neuropathy, 45% had pre-diabetes, and 15% had unrecognized diabetes.10 In terms of nephropathy, the prevalence of nephropathy was assessed in more than 5,000 Pima Indians who had pre-diabetes over a ten-year period. In patients with pre-diabetes, the rate of nephropathy was found to be related to higher fasting plasma glucose or two-hour post glucose load levels.21

In a study of 47,904 persons in New Zealand, A1c testing was offered as part of a screening campaign for hepatitis B. The goal of the study was to determine the association between A1c and mortality. For patients without a diagnosis of diabetes, the risk of all-cause mortality increased steadily as the A1c value increased. In fact, each 1% increase in A1c in patients without diabetes over the reference range of 4% to <5% was associated with a 16% increase in rate of mortality.11

Two additional studies also show that A1c concentration is associated with mortality. In a study by Khaw and colleagues of over 10,000 patients in England, the risk of cardiovascular disease and total mortality associated with A1c concentrations increased as A1c increased over 5%. An increase in A1c of 1% (using less than 5% as a baseline) was associated with a 24% and 28% increase in the relative risk of death in men and women, respectively.15

More recently, as a secondary analysis of the Candesartan in Heart Failure: Assessment of Reduction in Mortality and Morbidity (CHARM) study, it was noted that in both diabetic patients and nondiabetic patients with symptomatic chronic heart failure, that A1c concentration was an independent risk factor for cardiovascular death, hospitalization for heart failure, and total mortality.16

A number of studies evaluating pharmacotherapy of pre-diabetes have found that treatment of pre-diabetes can positively benefit both surrogate markers of cardiovascular disease and actual cardiovascular events. For example, in the DPP trial, lifestyle changes in patients with pre-diabetes had a beneficial effect on blood pressure and plasma lipids.12 In other trials, both troglitazone (Rezulin, no longer marketed) and acarbose (Precose) were associated with a reduced rate of carotid intima-media thickness in patients with pre-diabetes.13 Finally, a single study comparing acarbose to placebo in patients with pre-diabetes, showed that acarbose was associated with a reduced risk of composite cardiovascular outcome.14

• American Diabetes Association. Report of the expert committee on the diagnosis and classification of diabetes mellitus. Diabetes Care 1997;20:1183-97.
• Kuzuya T, Nakagawa S, Satoh J, et al. Report of the Committee on the classification and diagnostic criteria of diabetes mellitus. Diabetes Res Clin Pract 2002;55:65-85.
• Eldin WS, Emara M, Shoker A. Prediabetes: a must to recognize disease state. Int J Clin Pract 2008;62:642-48.
• Canadian Diabetes Association. Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada. Can J Diabetes 2003;27(suppl 2):S1-S152.
• Saudek CD, Herman WH, Sacks DB, et al. A new look at screening and diagnosing diabetes mellitus. J Clin Endocrinol Metab 2008;93:2447-53.
• American Diabetes Association. Standards of medical care in diabetes-2008. Diabetes Care 2008;31(suppl 1)S12-54.
• U.S. Preventive Services Task Force. Screening for type 2 diabetes mellitus in adults: U.S. Preventative Task Force recommendations statement. Ann Intern Med 2008;148:846-54.
• National Institutes of Health, American Diabetes Association. Diabetic retinopathy occurs in pre-diabetes. June 12, 2005. http://www.diabetes.org/uedocuments/DPPRetinopathy.REV.pdf. (Accessed August 9, 2008).
• Diabetes Prevention Program Research Group. Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med 2002;346:393-403.
• Smith AG, Singleton JR. Impaired glucose tolerance and neuropathy. Neurologist 2008;14:23-29.
• Brewer N, Wright CS, Travier N, et al. A New Zealand linkage study examining the associations between A1c concentrations and mortality. Diabetes Care 2008;31:1144-46.
• Rosenstock J. Reflecting on type 2 diabetes prevention: more questions than answers! Diabetes Obes Metab 2007;9(suppl 1):3-11.
• Nathan DM, Henry RR, Davidson MB, et al. Impaired fasting glucose and impaired glucose tolerance. Diabetes Care 2007;30:753-59.
• Chiasson JL, Josse RG, Gomis R, et al. Acarbose for the prevention of type 2 diabetes mellitus: the STOP-NIDDM randomized trial. Lancet 2002;359:2072-77.
• Khaw KT, Wareham N, Binggham S, et al. Association of hemoglobin A1c with cardiovascular disease and mortality in adults: the European prospective investigation into cancer in Norfolk. Ann Intern Med 2004;141:413-20.
• Gerstein HC, Swedberg K, Carlsson J, et al. The hemoglobin A1c as a progressive risk factor for cardiovascular death, hospitalization for heart failure, or death in patients with chronic heart failure. Arch Intern Med 2008;168:1699-1704.
• Gerstein HC, Yusuf S, Bosch J, et al. Effect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired glucose tolerance: a randomized controlled trial. Lancet 2006;368:1096-1105.
• Solski LV, Longyhore DS. Prevention of type 2 diabetes mellitus with angiotensin-converting-enzyme inhibitors. Am J Health-Syst Pharm 2008;65:935-40.
• Fonseca VA. Identification and treatment of prediabetes to prevent progression to type 2 diabetes. Clinical Cornerstone 2007;8:10-20.
• American College of Endocrinology Task Force on Pre-diabetes. American College of Endocrinology consensus statement on the diagnosis and management of pre-diabetes in the continuum of hyperglycemia-when do the risks of diabetes begin? Endocrine Practice 2008 (September issue). In press.
• Gagir MM, Roumain J, Hanson RL, et al. Plasma glucose and prediction of macrovascular disease and mortality. Diabetes Care 2000;23:1113-18.
• Yusef S, Ostergren JB, Gerstein HC, et al. Effect of candesartan on the development of a new diagnosis of diabetes mellitus in patients with heart failure. Circulation 2005;112:48-53.