ADA Updates Diabetes Care Standards

The American Diabetes Association, or ADA, recently released its "Standards of Medical Care in Diabetes -- 2008" position statement; the updated standards and supporting materials are available as a supplement to the January issue of Diabetes Care.

The new ADA standards are extensive and offer numerous practice recommendations -- far more than what the AAFP currently recommends. According to Douglas Campos-Outcalt, M.D., M.P.A., associate chair in the Department of Family and Community Medicine at the University of Arizona, Phoenix, and a former chair of the AAFP Commission on Clinical Policies and Research, that's because the ADA, which is a combination medical/research and advocacy group, takes a more aggressive approach to diabetes care than that advocated by the Academy, which formulates its clinical practice recommendations within the context of a more holistic and often complex primary care setting.

Still, it's helpful for FPs to know what the ADA is recommending so they're not caught off-guard should their patients with diabetes come to them with questions about their care plan.

The ADA standards include recommendations on screening for diabetes, as well as on monitoring and achieving glycemic goals, both in the general population and in specific patient populations. For example, the ADA now recommends that physicians consider screening adults of any age who are overweight or obese and have one or more additional risk factors for diabetes; the organization also recommends screening all overweight or obese patients beginning at age 45, even if they have no additional risk factors. The ADA classifies this as a "B" recommendation, which means it is supported by evidence from well-conducted cohort studies or from well-conducted case-control studies.

For all overweight and obese patients, the guidelines recommend repeat screening at intervals of no more than three years. This is a grade "E" recommendation, which means that it is based on expert consensus or clinical experience. The guidelines also recommend screening women who have had gestational diabetes mellitus for diabetes; this testing should take place six to 12 weeks postpartum and should be followed up with subsequent screening for the development of diabetes or prediabetes (grade E recommendation).

To prevent or delay the development of type 2 diabetes, the ADA recommends counseling patients about losing weight and increasing their physical activity. For very high-risk patients who are obese and younger that 60, the guidelines recommend that physicians consider prescribing metformin, in addition to lifestyle counseling (grade E recommendation). They also recommend monitoring any patients who exhibit signs of prediabetes every year (grade E recommendation).

As for glycemic goals in patients with diabetes, the guidelines state that the hemoglobin A1c goal for selected patients should be as close to normal (less than 6 percent) as possible without significant hypoglycemia (grade B recommendation). Less stringent A1c goals may be appropriate for diabetic patients who have a history of severe hypoglycemia, patients with limited life expectancies, children, patients who have comorbid conditions and those who have longstanding diabetes and minimal or stable microvascular complications (grade E recommendation).

The AAFP's recommendations for clinical preventive services include only two diabetes-specific statements: a recommendation to screen patients who have hypertension and hyperlipidemia for type 2 diabetes, and a finding of insufficient evidence to recommend for or against screening for gestational diabetes in asymptomatic women. Typically, the AAFP closely follows the United States Preventive Services Task Force, or USPSTF, in developing clinical care guidelines; in this instance, however, the USPSTF has published one additional diabetes-related statement, finding insufficient evidence to recommend for or against routinely screening asymptomatic adults for type 2 diabetes, impaired glucose tolerance or impaired fasting glucose.

Why are the ADA's recommendations so much more prescriptive than those the AAFP has developed? Campos-Outcalt says much of the difference can be attributed to the diverse patient bases treated by the physicians each of the two groups represents. Family physicians and other primary care physicians see and treat patients with diabetes who also have multiple comorbidities, while diabetologists focus solely on patients' diabetes. Many of the recommendations included in the ADA standards, he adds, particularly those that are guided only by expert consensus, are not applicable to patients who have multiple conditions and could even cause them harm.

However, the main reason the ADA's practice recommendations are so much more extensive than those of the AAFP or the USPSTF relates to the issue of level of evidence. According to Campos-Outcalt, the AAFP "takes a very rigorous scientific approach" when making clinical practice recommendations. All guidelines promulgated or supported by the AAFP are based strictly on the best available scientific evidence, preferably that derived from randomized controlled clinical trials or other high-quality studies. The ADA relies much more heavily on expert opinion.

For an approach to glycemic control that is more applicable to the primary care setting, Campos-Outcalt recommends a new guidance statement from the American College of Physicians. Included in the Sept. 18, 2007, issue of Annals of Internal Medicine, the guidance emphasizes that the goal for glycemic control should be as low as feasible for patients, but must take into account the individual patient's risk of complications, comorbidities, life expectancy and care preferences.