Richard Kahn

Bio: Richard Kahn is an academic researcher from American Diabetes Association. The author has contributed to research in topics: Diabetes mellitus & Type 2 diabetes. The author has an hindex of 38, co-authored 66 publications receiving 26729 citations.

Report of the expert committee on the diagnosis and classification of diabetes mellitus

Abstract: the growth of knowledge regarding the etiology and pathogenesis of diabetes has led many individuals and groups in the diabetes community to express the need for a revision of the nomenclature, diagnostic criteria, and classification of diabetes. As a consequence, it was deemed essential to develop an appropriate, uniform terminology and a functional, working classification of diabetes that reflects the current knowledge about the disease. (1)

Follow-up report on the diagnosis of diabetes mellitus.

Abstract: In 1997, an International Expert Committee was convened to reexamine the classification and diagnostic criteria of diabetes, which were based on the 1979 publication of the National Diabetes Data Group (1) and subsequent WHO study group (2). As a result of its deliberations, the Committee recommended several changes to the diagnostic criteria for diabetes and for lesser degrees of impaired glucose regulation (IFG/IGT) (3). The following were the major changes or issues addressed. 1) The use of a fasting plasma glucose (FPG) test for the diagnosis of diabetes was recommended, and the cut point separating diabetes from nondiabetes was lowered from FPG 140 mg/dl (7.8 mmol/l) to 126 mg/dl (7.0 mmol/l). (All glycemic values represent venous plasma.) This change was based on data that showed an increase in prevalence and incidence of diabetic retinopathy beginning at approximately a FPG of 126 mg/dl, as well as on the desire to reduce the discrepancy that existed in the number of cases detected by the FPG cut point of 140 mg/dl and the 2-h value in the OGTT (2-h plasma glucose [2-h PG]) of 200 mg/dl (11.1 mmol/l). 2) Normal FPG was defined as 110 mg/dl (6.1 mmol/l). 3) The use of HbA1c (A1C) as a diagnostic test for diabetes was not recommended. The primary reason for this decision was a lack of standardized methodology resulting in varying nondiabetic reference ranges among laboratories. 4) Although the OGTT (which consists of an FPG and 2-h PG value) was recognized as a valid way to diagnose diabetes, the use of the test for diagnostic purposes in clinical practice was discouraged for several reasons (e.g., inconvenience, less reproducibility, greater cost). The diagnostic category of impaired glucose tolerance (IGT) was retained to describe people whose FPG was 126 mg/dl but whose 2-h PG after a 75-g oral glucose challenge was 140–199 mg/dl. 5) The range of FPG levels between “normal” and that diagnostic for diabetes was named “impaired fasting glucose” (IFG). IFG identified people whose FPG ranged from 110 mg/dl (6.1 mmol/l) to 125 mg/dl (6.9 mmol/l). This construct was established so that there would be a fasting category analogous to IGT. The WHO consultation (4) also adopted most of the above conclusions. The two significant differences were that, whenever feasible, individuals with IFG should receive an OGTT to exclude the presence of diabetes, and the adoption of different criteria for the diagnosis of gestational diabetes. Since the 1997 Expert Committee report, many new data related to the diagnosis of diabetes have been published. First, many analyses of both old and new epidemiological data have examined the equivalence of the FPG and the 2-h PG to predict diabetes, and questions have been raised about the preference of the FPG test over the 2-h PG to diagnose diabetes (5– 7). Second, the IGT category has now been associated with cardiovascular disease (CVD) risk factors (8–10) and CVD events (10,11), whereas IFG is much less strongly associated with CVD events and CVD mortality (10,11). Third, the National Glycosylated Hemoglobin Standardization Program (NGSP) has now ensured that most laboratories in the U.S. perform the assays using standardized controls and report glycated hemoglobin results in a manner traceable to the assay used in the Diabetes Control and Complications Trial (DCCT) (12). These development s have improved as say performance and now allow caregivers and patients to compare reported results obtained among laboratories. Additional studies have suggested that the A1C may assist in diagnosing diabetes (13–17). Finally, data from major clinical trials that tested whether the progression from IGT to diabetes could be delayed or prevented by a treatment intervention have produced concordant results: intensive lifestyle modification (nutritional and exercise interventions) (18,19), metformin (19,20), and acarbose (20,21) were effective to variable degrees. In addition, a thiazolidinedione drug (troglitazone) reduced the incidence of diabetes in high-risk women with prior gestational diabetes (22). An inherent difficulty in the diagnosis of diabetes is the present lack of an identified unique qualitative biological marker that separates all people with diabetes from all nondiabetic individuals. The closest such characteristic for practical purposes is diabetic retinopathy, but this suffers from the obvious defect that in most diabetic patients, retinopathy usually becomes evident years after the recognized onset of diabetes. The lack of a suitable, unique marker of diabetes has led to reliance on the metabolic abnormality historically associated with the disease, i.e., hyperglycemia (as measured by the FPG or 2-h PG) as the most useful diagnostic test. The selection of diagnostic cut points for these tests rests on two ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ● ●

The Metabolic Syndrome: Time for a Critical Appraisal Joint statement from the American Diabetes Association and the European Association for the Study of Diabetes

Abstract: The term "metabolic syndrome" refers to a clustering of specific cardiovascular disease (CVD) risk factors whose underlying pathophysiology is thought to be related to insulin resistance. Since the term is widely used in research and clinical practice, we undertook an extensive review of the literature in relation to the syndrome's definition, underlying pathogenesis, and association with CVD and to the goals and impact of treatment. While there is no question that certain CVD risk factors are prone to cluster, we found that the metabolic syndrome has been imprecisely defined, there is a lack of certainty regarding its pathogenesis, and there is considerable doubt regarding its value as a CVD risk marker. Our analysis indicates that too much critically important information is missing to warrant its designation as a "syndrome." Until much needed research is completed, clinicians should evaluate and treat all CVD risk factors without regard to whether a patient meets the criteria for diagnosis of the "metabolic syndrome."

Clinical Management of Metabolic Syndrome Report of the American Heart Association/National Heart, Lung, and Blood Institute/American Diabetes Association Conference on Scientific Issues Related to Management

Abstract: The National Cholesterol Education Program’s Adult Treatment Panel III report (ATP III)1 identified the metabolic syndrome as a multiplex risk factor for cardiovascular disease (CVD) that is deserving of more clinical attention. Subsequently, the National Heart, Lung, and Blood Institute (NHLBI), in collaboration with the American Heart Association (AHA), convened a conference to examine scientific issues related to definition of the metabolic syndrome.2 The present report summarizes a second conference devoted to clinical management of the metabolic syndrome, which was sponsored by the AHA in partnership with the NHLBI and cosponsored by the American Diabetes Association (ADA). This latter conference considered the following issues: (1) pathogenesis and presentation of the metabolic syndrome, (2) management of underlying risk factors, (3) management of metabolic risk factors, and (4) unresolved issues and research challenges. The conference on definition2 confirmed CVD as a major clinical outcome of metabolic syndrome and identified 6 major components of the syndrome: abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, insulin resistance ± glucose intolerance, a proinflammatory state, and a prothrombotic state. The follow-up conference on management was structured around therapies for these components. Clinical recognition of the metabolic syndrome is generally based on finding several well-recognized signs in clinical practice: abdominal obesity, elevated triglycerides, reduced HDL cholesterol, raised blood pressure, and elevated plasma glucose. In addition, research shows that other components not routinely measured commonly aggregate with the major components: elevated apolipoprotein B, small LDL particles, insulin resistance and hyperinsulinemia, impaired glucose tolerance (IGT), elevated C-reactive protein (CRP), and variation in coagulation factors (eg, plasminogen activator inhibitor [PAI]-1 and fibrinogen). The conference on definition2 also emphasized that risk for type 2 diabetes is higher in persons with metabolic syndrome and that diabetes is a major risk factor for CVD. It also examined various criteria for …

How Do We Define Cure of Diabetes

Abstract: The mission of the American Diabetes Association is “to prevent and cure diabetes and to improve the lives of all people affected by diabetes.” Increasingly, scientific and medical articles (1) and commentaries (2) about diabetes interventions use the terms “remission” and “cure” as possible outcomes. Several approved or experimental treatments for type 1 and type 2 diabetes (e.g., pancreas or islet transplants, immunomodulation, bariatric/metabolic surgery) are of curative intent or have been portrayed in the media as a possible cure. However, defining remission or cure of diabetes is not as straightforward as it may seem. Unlike “dichotomous” diseases such as many malignancies, diabetes is defined by hyperglycemia, which exists on a continuum and may be impacted over a short time frame by everyday treatment or events (medications, diet, activity, intercurrent illness). The distinction between successful treatment and cure is blurred in the case of diabetes. Presumably improved or normalized glycemia must be part of the definition of remission or cure. Glycemic measures below diagnostic cut points for diabetes can occur with ongoing medications (e.g., antihyperglycemic drugs, immunosuppressive medications after a transplant), major efforts at lifestyle change, a history of bariatric/metabolic surgery, or ongoing procedures (such as repeated replacements of endoluminal devices). Do we use the terms remission or cure for all patients with normal glycemic measures, regardless of how this is achieved? A consensus group comprised of experts in pediatric and adult endocrinology, diabetes education, transplantation, metabolism, bariatric/metabolic surgery, and (for another perspective) hematology-oncology met in June 2009 to discuss these issues. The group considered a wide variety of questions, including whether it is ever accurate to say that a chronic illness is cured; what the definitions of management, remission, or cure might be; whether goals of managing comorbid conditions revert to those of patients without diabetes if someone is …

Reduction in the incidence of type 2 diabetes with lifestyle intervention or metformin.

Abstract: Background Type 2 diabetes affects approximately 8 percent of adults in the United States. Some risk factors — elevated plasma glucose concentrations in the fasting state and after an oral glucose load, overweight, and a sedentary lifestyle — are potentially reversible. We hypothesized that modifying these factors with a lifestyle-intervention program or the administration of metformin would prevent or delay the development of diabetes. Methods We randomly assigned 3234 nondiabetic persons with elevated fasting and post-load plasma glucose concentrations to placebo, metformin (850 mg twice daily), or a lifestyle modification program with the goals of at least a 7 percent weight loss and at least 150 minutes of physical activity per week. The mean age of the participants was 51 years, and the mean body-mass index (the weight in kilograms divided by the square of the height in meters) was 34.0; 68 percent were women, and 45 percent were members of minority groups. Results The average follow-up was 2.8 years. The incidence of diabetes was 11.0, 7.8, and 4.8 cases per 100 person-years in the placebo, metformin, and lifestyle groups, respectively. The lifestyle intervention reduced the incidence by 58 percent (95 percent confidence interval, 48 to 66 percent) and metformin by 31 percent (95 percent confidence interval, 17 to 43 percent), as compared with placebo; the lifestyle intervention was significantly more effective than metformin. To prevent one case of diabetes during a period of three years, 6.9 persons would have to participate in the lifestyle-intervention program, and 13.9 would have to receive metformin. Conclusions Lifestyle changes and treatment with metformin both reduced the incidence of diabetes in persons at high risk. The lifestyle intervention was more effective than metformin.

Diagnosis and Management of the Metabolic Syndrome An American Heart Association/National Heart, Lung, and Blood Institute Scientific Statement

Abstract: The metabolic syndrome has received increased attention in the past few years. This statement from the American Heart Association (AHA) and the National Heart, Lung, and Blood Institute (NHLBI) is intended to provide up-to-date guidance for professionals on the diagnosis and management of the metabolic syndrome in adults. The metabolic syndrome is a constellation of interrelated risk factors of metabolic origin— metabolic risk factors —that appear to directly promote the development of atherosclerotic cardiovascular disease (ASCVD).1 Patients with the metabolic syndrome also are at increased risk for developing type 2 diabetes mellitus. Another set of conditions, the underlying risk factors , give rise to the metabolic risk factors. In the past few years, several expert groups have attempted to set forth simple diagnostic criteria to be used in clinical practice to identify patients who manifest the multiple components of the metabolic syndrome. These criteria have varied somewhat in specific elements, but in general they include a combination of both underlying and metabolic risk factors. The most widely recognized of the metabolic risk factors are atherogenic dyslipidemia, elevated blood pressure, and elevated plasma glucose. Individuals with these characteristics commonly manifest a prothrombotic state and a pro-inflammatory state as well. Atherogenic dyslipidemia consists of an aggregation of lipoprotein abnormalities including elevated serum triglyceride and apolipoprotein B (apoB), increased small LDL particles, and a reduced level of HDL cholesterol (HDL-C). The metabolic syndrome is often referred to as if it were a discrete entity with a single cause. Available data suggest that it truly is a syndrome, ie, a grouping of ASCVD risk factors, but one that probably has more than one cause. Regardless of cause, the syndrome identifies individuals at an elevated risk for ASCVD. The magnitude of the increased risk can vary according to which components of the syndrome are …

Standards of Medical Care in Diabetes

Abstract: XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.