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Researchers focus on diabetes prevalence and control among urban black adults and diabetes understanding by the undereducated

Type 2 diabetes, which used to affect only adults, has increased alarmingly among adolescents and is reaching epidemic proportions in the United States. In 1994, 12 percent of adults aged 40 to 74 years were affected by diabetes. Type 2 diabetes affects more minorities than whites, with incidence nearly tripling among blacks in the past 30 years. High levels of blood sugar (hyperglycemia) and longer duration of the disease increase the risk of serious complications ranging from blindness to kidney failure.

A study supported in part by the Agency for Healthcare Research and Quality (HS09722) and led by Lawrence S. Phillips, M.D., of Emory University, found a high prevalence of obesity and poor blood sugar (glycemic) control among young urban blacks with diabetes. A second study by the same group is testing whether endocrinologist-supported primary care strategies can improve glycemic control among black adults who have diabetes. A third AHRQ-supported study (HS10281 and HS10856) led by A. Eugene Washington, M.D., of the University of California, San Francisco, and John Piette, Ph.D., of the University of Michigan Medical School, revealed that primary care doctors rarely check whether their diabetic patients understand instructions that often are critical to managing their disease. The three studies are described here.

El-Kebbi, I.M., Cook, C.B., Ziemer, D.C., and others (2003, January). "Association of younger age with poor glycemic control and obesity in urban African Americans with type 2 diabetes." Archives of Internal Medicine 163, pp. 69-75.

Younger black adults with type 2 diabetes are more obese and have worse glycemic control than their older counterparts, despite a higher prevalence of insulin use, according to this study. Since younger study patients were more obese than older patients, they would be expected to be more insulin-resistant and possibly require more aggressive therapy to achieve glycemic control, explain the investigators.

They retrospectively studied 2,539 predominantly black patients with type 2 diabetes, who were seen at a hospital-based outpatient diabetes clinic between 1991 and 1998. They examined the contribution of age to glucose control (measured by hemoglobin A1c or HbA1c) at the initial visit and after an average of 8 months of care by a multidisciplinary team that emphasized lifestyle modifications and self-management skills. The researchers also analyzed the HbA1c data of 597 people with diabetes treated at a neighborhood primary care clinic in 1999.

The researchers divided patients into four age groups in each clinic: less than 30 years, 30 to 49 years, 50 to 69 years, and more than 69 years old. Despite the provision of intensive dietary education, there was no clinically significant change in body mass index (BMI, calculated as weight in kilograms divided by the square of height in meters) in any age group. Younger age, longer duration of diabetes, higher BMI, less frequent clinic visits, and treatment with oral medication or insulin were associated with higher HbA1c level (worse glucose control) at followup at both clinics.

Of the four hospital-based clinic groups ranked in order of increasing age, 77 percent (under 30), 63 percent (30 to 49), 53 percent (50 to 69), and 40 percent (70 or older) were obese, with a BMI of 30 or more and little change over time. At baseline, 19 to 23 percent of patients had an HbA1c level less than 7 percent (considered controlled and the target HbA1c), increasing to 33 to 41 percent at 8 months, with no significant difference between age groups. However, the prevalence of having an HbA1c level greater than 8 percent (which should prompt intensification of therapy) at baseline increased from 54 to 75 percent with decreasing age. The researchers recommend more effective measures for weight reduction, use of aggressive medication therapy, and more frequent clinic visits to improve diabetes control.

Phillips, L.S., Hertzberg, V.S., Cook, C.B., and others (2002). "The Improving Primary Care of African Americans with Diabetes (IPCAAD) project: Rationale and design." Controlled Clinical Trials 23, pp. 554-569.

Although blacks with diabetes typically have poorer glycemic control and more serious diabetes complications than others, they are not often treated in specialty clinics, where patients are instructed in home blood glucose monitoring and diet (avoidance of refined sugars and saturated fats) and are advised to exercise. Instead, most blacks with diabetes are managed in a primary care setting where measurement of HbA1c, dilated eye exams, and foot exams are infrequent, and hypertension is treated less aggressively than recommended.

These researchers have developed a program of endocrinologist-supported strategies focused on primary care providers to improve diabetes management in primary care sites. In their Improving Primary Care of African Americans with Diabetes (IPCAAD) project, they randomized over 2,000 black patients with type 2 diabetes being seen at hospital-based medical clinics to receive one of four types of care for their diabetes.

These included: usual care (usual diabetes education); endocrinologist-supported interventions of computerized reminders that recommend individualized changes in therapy; endocrinologist discussions providing performance feedback on patient management (for example, whether the primary care doctors are achieving target glucose levels [below 7 percent] in their patients, intensifying therapy when glucose levels are above that, and how their achievements compare with clinic peers); and computerized reminders and endocrinologist discussion. The IPCAAD project is the first comprehensive intervention aimed at sustained improvement in diabetes management of urban blacks in the primary care setting.

The researchers have established that this approach works in the specialty diabetes clinic and are hoping it can be successfully transferred to primary care clinics. In the project, ongoing through 2003, they will assess patient outcomes related to both microvascular disease (HbA1c, which reflects average glucose levels over a 2-month period) and macrovascular disease (blood pressure and lipids), as well as provider performance. The IPCAAD project is a joint effort of endocrinologists, primary care doctors, and social scientists.

Schillinger, D., Piette, J., Grumbach, K., and others (2003). "Closing the loop: Physician communication with diabetic patients who have low health literacy." Archives of Internal Medicine 163, pp. 83-90.

This study found that ethnically diverse diabetes patients, whose doctors asked them during their visit if they understood new instructions about medication or other disease management issues, were nearly nine times more likely to have reasonable glucose control (HbA1c of 8.6 percent or less) than patients whose doctors did not assess their understanding. The primary care doctors caring for patients with type 2 diabetes and low functional health literacy (FHL, corresponding to a 4th to 6th grade level) checked to see if these patients understood them in only one out of five visits, even though asking such questions did not make visits significantly longer than those in which the doctors did not confirm patient understanding (20.3 vs. 22.1 minutes).

Patients with low FHL levels are especially likely to have difficulty recalling and understanding medical information. They typically have problems reading medication labels, interpreting blood glucose values or dosing schedules, and conceptualizing risk. The low FHL among minorities, coupled with their greater burden of diabetes, suggests that problems with health communication may contribute to disparities in diabetes care for minorities, note the researchers. They analyzed audiotapes of visits between 38 physicians and 74 English-speaking patients with type 2 diabetes and low FHL (functional health literacy was assessed by an initial questionnaire) at two primary care clinics of a public hospital.

Doctors conveyed at least one new concept in 61 (82 percent) of 74 visits. Among these 61 visits, doctors conveyed a mean of two new concepts, more than half of which involved a medication change. Physicians assessed recall or comprehension at least once in 20 percent of these 61 visits. When asked by physicians to restate or interpret new concepts, patients responded incorrectly 47 percent of the time (7 of 15 new concepts). In all seven instances, the physician provided further tailored information but then did not assess whether the patient fully understood it.

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