Clinical inertia.

Medicine has traditionally focused on relieving patient symptoms. However, in developed countries, maintaining good health increasingly involves management of such problems as hypertension, dyslipidemia, and diabetes, which often have no symptoms. Moreover, abnormal blood pressure, lipid, and glucose values are generally sufficient to warrant treatment without further diagnostic maneuvers. Limitations in managing such problems are often due to clinical inertia-failure of health care providers to initiate or intensify therapy when indicated. Clinical inertia is due to at least three problems: overestimation of care provided; use of "soft" reasons to avoid intensification of therapy; and lack of education, training, and practice organization aimed at achieving therapeutic goals. Strategies to overcome clinical inertia must focus on medical students, residents, and practicing physicians. Revised education programs should lead to assimilation of three concepts: the benefits of treating to therapeutic targets, the practical complexity of treating to target for different disorders, and the need to structure routine practice to facilitate effective management of disorders for which resolution of patient symptoms is not sufficient to guide care. Physicians will need to build into their practice a system of reminders and performance feedback to ensure necessary care.

Hypoglycemia in patients with type 2 diabetes mellitus.

BACKGROUND: Although hypoglycemia is the most common complication of intensive diabetes therapy, there is little information about risk factors for hypoglycemia in patients with type 2 diabetes mellitus. OBJECTIVE: To determine the prevalence and predisposing factors for hypoglycemia in patients with type 2 diabetes. METHODS: Retrospective, cross-sectional analysis set in an outpatient specialty diabetes clinic. We included those patients who had baseline and follow-up visits from April 1 through October 31, 1999. Hypoglycemia was defined as typical symptoms relieved by eating, and/or blood glucose level of less than 60 mg/dL (<3.3 mmol/L). Univariate and multivariate logistic regression were used to determine the contributions to hypoglycemia of age, sex, diabetes duration, body mass index (calculated as weight in kilograms divided by the square of height in meters), fasting plasma glucose level, glycosylated hemoglobin (HbA(1c)) level, type of therapy, and previous episodes at the follow-up visit. RESULTS: We studied 1055 patients. Prevalence of hypoglycemic symptoms was 12% (9/76) for patients treated with diet alone, 16% (56/346) for those using oral agents alone, and 30% (193/633) for those using any insulin (P<.001). Severe hypoglycemia occurred in only 5 patients (0.5%), all using insulin. Multiple logistic regression analysis demonstrated that insulin therapy, lower HbA(1c) level at follow-up, younger age, and report of hypoglycemia at the baseline visit were independently associated with increased prevalence of hypoglycemia. There were no significant predictors of severe hypoglycemia. CONCLUSIONS: Mild hypoglycemia is common in patients with type 2 diabetes undergoing aggressive diabetes management, but severe hypoglycemia is rare. Concerns about hypoglycemia should not deter efforts to achieve tight glycemic control in most patients with type 2 diabetes.

Comorbidity and glycemic control in patients with type 2 diabetes.

BACKGROUND: It is commonly believed that good glycemic control is hard to achieve in patients with diabetes mellitus and concurrent chronic illnesses. OBJECTIVE: To determine the impact of comorbidity on glycemic control at presentation and subsequent follow-up in patients with type 2 diabetes. METHODS: We studied 654 consecutive patients who presented to a diabetes clinic in 1997. Comorbidity was rated using the Chronic Disease Score (CDS) index, which is a validated, weighted score that takes into account the patient's age, sex, and classes of medications. Univariate and multivariate linear regressions were used to determine the contribution of age, body mass index (calculated as weight in kilograms divided by the square of height in meters), diabetes duration, type of therapy, and CDS to initial hemoglobin A(1c) (HbA(1c)) level. A similar analysis was performed for the 169 patients with follow-up HbA(1c) levels 6 months after presentation. RESULTS: Patients were 90% African American, and 66% female, with average age of 53 years. Average diabetes duration was 5 years; body mass index, 33; HbA(1c) level, 8.8%; and CDS, 1121 (range, 232-7953). At presentation, patients with higher CDSs tended to be older and to have a lower HbA(1c) level, but multivariate linear regression showed that receiving pharmacological therapy, younger age, and having a lower C-peptide level were the only significant contributors to HbA(1c) level. In the 169 follow-up patients, presenting characteristics were not significantly different from those of the full cohort: average initial HbA(1c) level was 8.8%; CDS, 1073. Their HbA(1c) level at 6 months averaged 7.5% and the CDS had no significant impact on their follow-up HbA(1c) level. CONCLUSION: Comorbidity does not appear to limit achievement of good glycemic control in patients with type 2 diabetes.

Diabetes in urban African-Americans. XIX. Prediction of the need for pharmacological therapy.

OBJECTIVE: To develop a prediction rule that will identify patients who will require pharmacological therapy within 6 months of first presentation to a diabetes clinic. RESEARCH DESIGN AND METHODS: Among the patients who came to the Grady Diabetes Clinic between 1991 and 1997, we randomized 557 frequent attenders to a development group and 520 frequent attenders to a validation group. Using multiple logistical regression, we derived a prediction rule in the development group to project whether patients would require pharmacological intervention to achieve HbA1c levels <7% after 6 months. The utility of the prediction rule was then confirmed in the validation group and tested prospectively on an additional group of 93 patients who presented from 1997 to 1998. Performance of the prediction rule was assessed using receiver operating characteristic (ROC) curves. RESULTS: The rule (-4.469 + 1.932 x sulfonylurea Rx + 1.334 x insulin Rx + 0.196 x duration + 0.468 x fasting glucose, where "Rx" indicates a prescription) predicted the need for pharmacological intervention in the development group (P < 0.0001). Use of insulin or sulfonylurea therapy at presentation, duration of diabetes, and fasting glucose levels were significant predictors of the future need for pharmacological management. The prediction rule also performed well in the validation group (positive predictive value 90%, correlation between predicted and observed need for medical management 0.99). ROC curves confirmed the value of the prediction rule (area under the curves was 0.91 for the development group, 0.85 for the validation group, and 0.81 for the prospective group). CONCLUSIONS: Early identification of individuals who will require pharmacological intervention to achieve national standards for glycemic control can be achieved with high probability, thus allowing for more efficient management of diabetes.

The pattern of dyslipidemia among urban African-Americans with type 2 diabetes.

OBJECTIVE: To analyze lipid profiles from a large sample of African-American patients with type 2 diabetes who receive care at an urban outpatient diabetes clinic. RESEARCH DESIGN AND METHODS: Fasting serum lipid profiles of 4,014 African-Americans and 328 Caucasians with type 2 diabetes were retrieved from a computerized registry. American Diabetes Association criteria were applied to classify LDL cholesterol, HDL cholesterol, and triglyceride (TG) levels into risk categories. The proportion of patients who had none, one, two, and three lipoprotein concentrations outside of recommended clinical targets was examined. Multiple logistical regression analyses were performed to determine the influence of sex and race on the probability of having a lipid level outside of the recommended target. RESULTS: The percentages of African-Americans with high-, borderline-, and low-risk LDL cholesterol concentrations were 58, 26, and 16%, respectively, and the percentages for Caucasians were 54, 29, and 16%, respectively (P = 0.51). For HDL cholesterol, 41, 33, and 26% of African-Americans were in the high-, borderline-, and low-risk categories, respectively, compared with 73, 18, and 9% of Caucasians, respectively (P < 0.0001). Nearly 81% of African-Americans had TG concentrations that were in the low-risk category compared with only 50% of Caucasians. More women than men had high-risk LDL and HDL cholesterol profiles. The most common pattern of dyslipidemia was an LDL cholesterol level above target combined with an HDL cholesterol level below target, which was detected in nearly 50% of African-Americans and 42% of Caucasians. African-Americans had lower odds of having an HDL cholesterol or TG level outside of target. African-American women, compared to men, had greater probabilities of having abnormal levels of LDL and HDL, but a lower likelihood of having a TG level above goal. CONCLUSIONS: In a large sample of urban type 2 diabetic patients receiving care at a diabetes treatment program, race and sex differences in serum lipid profiles were present. Because hypertriglyceridemia was rare among African-American subjects, interventions will need to focus primarily on improving their LDL and HDL cholesterol levels. Further studies are required regarding how to best adapt these observed differences into more effective strategies to optimize lipid levels for this population of diabetic patients and to determine whether similar patterns of dyslipidemia occur in other clinical settings.

Diabetes in urban African-Americans. XV. Identification of barriers to provider adherence to management protocols.

OBJECTIVE: To determine whether health care providers appropriately identify patients with poor glycemic control and to investigate reasons why providers may fail to intensify therapy in these patients. RESEARCH DESIGN AND METHODS: Our management protocol calls for providers to advance diabetes therapy in patients with fasting plasma glucose levels > 7.8 mmol/l or random plasma glucose levels > 10.0 mmol/l. During a 3-month period, providers completed a questionnaire at the end of individual patient visits by asking whether the patient was well controlled and whether therapy was advanced. If therapy was not advanced in patients perceived to have poor control, providers were asked to provide a justification. RESULTS: Providers appropriately identified 88% of well-controlled patients and 94% of patients with poor glycemic control. Out of 1,144 patient visits, control was reported to be good in 508 and poor in 636. In these 636 visits, therapy was advanced in 490 but not in 146 visits. The dominant reasons for failure to intensify therapy were the perception by the provider that control was improving (34%) or the belief that the patient was not compliant with diet or medications (25%). Less common reasons included acute illness, patient refusal, and recurrent hypoglycemia. Based on fasting glucose levels, protocol adherence was 55% before the questionnaire, 64% during the questionnaire (P = 0.006), and 63% afterwards. CONCLUSIONS: Providers in a specialty diabetes clinic appropriately classified patients according to glycemic control and tended to intensify therapy when indicated in most poorly controlled patients. Provider self-survey of behavior and decision making may be an effective strategy to improve adherence to management protocols.

Diabetes in urban African-Americans. XVII. Availability of rapid HbA1c measurements enhances clinical decision-making.

OBJECTIVE: To assess the impact of rapid-turnaround HbA1c results on providers' clinical decision-making and on follow-up HbA1c levels. RESEARCH DESIGN AND METHODS: The research design was a randomized clinical trial in which rapid HbA1c results were made available to providers on even days of the month (rapid, n = 575), but delayed by 24 h on odd days (conventional, n = 563). Adjustment of therapy for patients with type 2 diabetes was considered appropriate if therapy was intensified for HbA1c values >7% or not intensified for HbA1c values < or =7%. A post-hoc analysis was also performed using patients (n = 574) who returned for follow-up 2-7 months later to ascertain the effect of rapid HbA1c availability on subsequent glycemic control. RESULTS: Rapid HbA1c availability resulted in more appropriate management compared with conventional HbA1c availability (79 vs. 71%, P = 0.003). This difference was due mainly to less frequent intensification when HbA1c levels were < or =7% (10 vs. 22%, P < 0.0001) and slightly to more frequent intensification for patients with HbA1c values >7% (67 vs. 63%, P = 0.33). For both groups, intensification was greatest for patients on insulin (51%) compared with patients on oral agents (35%) and diet alone (14%) (P < 0.0001). Regression analysis confirmed that providers receiving conventional HbA1c results were more likely to intensify therapy in patients who already had HbA1c levels < or =7%. Over 2-7 months of follow-up, HbA1c rose more in patients with conventional HbA1c results compared with rapid results (0.8 vs. 0.4%, P = 0.02). In patients with initial HbA1c >7%, rapid HbA1c results had a favorable impact on follow-up HbA1c independent of the decision to intensify therapy (P = 0.03). CONCLUSIONS: Availability of rapid HbA1c determinations appears to facilitate diabetes management. The more favorable follow-up HbA1c profile in the rapid HbA1c group occurs independently of the decision to intensify therapy, suggesting the involvement of other factors such as enhanced provider and/or patient motivation.

Diabetes in urban African-Americans. XVI. Overcoming clinical inertia improves glycemic control in patients with type 2 diabetes.

OBJECTIVE: Diabetes care can be limited by clinical inertia-failure of the provider to intensify therapy when glucose levels are high. Although disease management programs have been proposed as a means to improve diabetes care, there are few studies examining their effectiveness in patient populations that have traditionally been underserved. We examined the impact of our management program in the Grady Diabetes Unit, which provides care primarily to urban African-American patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: We assessed glycemic outcomes in patients with type 2 diabetes who had an intake evaluation between 1992 and 1996 and who were identified on the basis of compliance with keeping the recommended number of return visits. For 698 patients, we analyzed changes in HbA1c values between baseline and follow-up visits at 6 and 12 months, and the proportion of patients achieving a target value of < or =7.0% at 12 months. Since a greater emphasis on therapeutic intensification began in 1995, we also compared HbA1c values and clinical management in 1995-1996 with that of 1992-1994. RESULTS: HbA1c averaged 9.3% on presentation. After 12 months of care, HbA1c values averaged 8.2, 8.4, 8.5, 7.7, and 7.3% for the 1992-1996 cohorts, respectively, and were significantly lower compared with values on presentation (P < 0.0025); the average fall in HbA1c was 1.4%. The percentage of patients achieving a target HbA1c < or =7.0% improved progressively from 1993 to 1996, with 57% of the patients attaining this goal in 1996. Mean HbA1c after 12 months was 7.6% in 1995-1996, significantly improved over the level of 8.4% in 1992-1994 (P < 0.0001). HbA1c levels after 12 months of care were lower in 1995-1996 versus 1992-1994, whether patients were managed with diet alone, oral agents, or insulin (P < 0.02). Improved HbA1c in 1995-1996 versus 1992-1994 was associated with increased use of pharmacologic therapy CONCLUSIONS: Structured programs can improve glycemic control in urban African-Americans with diabetes. Self-examination of performance focused on overcoming clinical inertia is essential to progressive upgrading of care.

Diabetes in urban African-Americans. VI. Utility of fasting or random glucose in identifying poor glycemic control.

OBJECTIVE: African-Americans have an increased prevalence of both diabetes and diabetes complications, creating an imperative for improved metabolic control. Because American Diabetes Association guidelines recommend that action be taken when HbA1c is > 8.0%, but access to rapid-turnaround HbA1c assays remains limited, we tested the utility of fasting and random plasma glucose cutoffs as indicators of HbA1c > 8.0%. RESEARCH DESIGN AND METHODS: Using receiver operating characteristics (ROC) analysis, we evaluated the sensitivity, specificity, and predictive value of fasting and random plasma glucose measurements in identifying an HbA1c > 8.0% (fasting n = 974, random n = 552). The population studied was predominantly African-American, middle-aged, and non-insulin-dependent. RESULTS: Fasting plasma glucose was a significant indicator of HbA1c > 8.0%, both in the whole group and in subgroups for diet, sulfonylureas, and insulin; the corresponding areas under the ROC curve were 0.87, 0.90, 0.87, and 0.84, respectively (all P < 0.0001). A fasting plasma glucose cutoff of > 9.2 mmol/l (165 mg/dl) provided a sensitivity of 80% and a specificity of 83% for the whole group and a 77% positive predictive value. Random plasma glucose was also a good indicator of HbA1c > 8.0%, both in the whole group and in subgroups for diet, sulfonylureas, and insulin; the corresponding areas under the ROC curve were 0.85, 0.91, 0.85, and 0.77, respectively (all P < 0.0001). A cutoff > 9.8 mmol/l (177 mg/dl) provided a sensitivity of 78% and a specificity of 77% for the whole group and a 78% positive predictive value. Overall, a plasma glucose > 11.1 mmol/l (200 mg/dl) identified an HbA1c > 8.0% with a predictive value of approximately 90% if done while fasting and a predictive value of approximately 80-85% if random. The utility of both fasting and random plasma glucose cutoffs was subsequently confirmed in a prospective study of another 2,309 and 1,396 patients, respectively. CONCLUSIONS: Although glucose levels cannot replace HbA1c determinations, measurement of fasting or random plasma glucose may be used during a clinic visit to identify poorly controlled type 2 patients with reasonable certainty and allow timely patient education and therapeutic intervention.

Diabetes in urban African Americans: functional health literacy of municipal hospital outpatients with diabetes.

Functional health literacy was assessed in 63 patients from the diabetes outpatient clinic, 20 from the general medicine clinic, and a total of 48 from two satellite medical clinics. All patients received a demographic questionnaire, visual screening, and the Test of Functional Health Literacy in Adults, an instrument with good validity and internal consistency used to measure the ability to read and understand medical instructions. Functional health literacy was adequate in only 47% of new patients at the diabetes clinic and only 25% of established patients at all sites. There were no significant differences in functional health literacy among established patients across all sites. Overall, patients' mean functional health literacy level was inadequate to marginal. Of the patients with inadequate functional health literacy, 43% denied difficulty in reading. Patient education strategies and materials are needed to address this important barrier to healthcare delivery.

Diabetes in urban African-Americans. IX. Provider adherence to management protocols.

OBJECTIVE: Staged diabetes management should permit glycemic goals to be attained in a timely manner, but the success of such an approach requires conformity by health care providers. To test performance, we analyzed the adherence of practitioners to a protocol for staged management of NIDDM patients. RESEARCH DESIGN AND METHODS: Records of patients treated at the Grady Memorial Hospital Diabetes Clinic were reviewed retrospectively over a 3-year period. For each patient, intensification of therapy was indicated if fasting plasma glucose was > 7.8 mmol/l and a prior HbA1c was > 7.0%. Protocols dictated a progression from dietary therapy alone to increasing dosages of sulfonylureas to increasing dosages of insulin. Patients were seen at bimonthly intervals. RESULTS: During the 3-year period, 1,051 patient visits met protocol criteria for intensification. Adherence to the protocol improved significantly in the 3rd year compared with the first 2 years (30, 31, and 47% adherence in the 1st, 2nd, and 3rd years, respectively). Patients treated with diet alone were significantly less likely to have their therapy intensified than patients on sulfonylureas or insulin (intensification rates 25, 41, and 47%, respectively). In the management of patients treated with diet alone, practitioners were reluctant to intensify therapy at early visits, but were more likely to do so later, 19% of patients beyond goal range at the 2-month visit were started on pharmacological therapy vs. 28% at the 4-month visit, and 39% at the 6-month visit (P < 0.01). In contrast, there was no significant difference in the frequency of therapy intensification between early and late visits for patients on sulfonylureas or insulin. Practitioners appeared to base the decision to intensify on the fasting plasma glucose level more than on the most recent HbA1c. Age did not appear to be a significant factor in the decision to intensify. CONCLUSIONS: Although staged management protocols constitute critical tools to achieve glycemic goals, the adherence of health care providers may be suboptimal. Special efforts may be needed to assure compliance.

Diabetes in urban African Americans. V. Use of discussion groups to identify barriers to dietary therapy among low-income individuals with non-insulin-dependent diabetes mellitus.

Dietary therapy remains an integral part of diabetes management. The study objective was to identify potential barriers to dietary adherence among low-income, urban black patients with non-insulin-dependent diabetes. Forty-five patients participated in discussion group interviews that consisted of open-ended questions. Four problem areas were identified: habitual, economic, social, and conceptual. Most patients felt that the recommended meal plans were lacking in taste, and the cost of low-fat and sugar-free items was perceived as a major drawback. Lack of family support and family pressure to use fat-containing food seasoning were frequent problems. Participants had trouble following the food exchange system and analyzing food labels. Feedback suggested that dietary strategies may need to be revised to provide appropriate menus, identify low-cost foods, involve patients' families, and teach patients how to make healthy food choices. The discussion group approach was quick, simple, and could be easily translated to other settings.

Regulation of glucose transport by pioglitazone in cultured muscle cells.

Recent evidence suggests that pioglitazone, a thiazolidinedione hypoglycemic agent, acts by increasing insulin responsiveness at the peripheral level. We studied the effect of pioglitazone (1 to 50 micrograms/mL) on the glucose transporter and glucose transport in BC3H-1 cells, a continuously cultured skeletal muscle cell line lacking the myoD transcription factor required for cell fusion. Glucose-fed cells (25 mmol/L) responded to insulin with a more than twofold increase in 2-deoxyglucose (2-DOG) uptake as compared with baseline. Treating these cells with pioglitazone alone for 24 hours resulted in a dose-dependent increase in hexose uptake, reaching twofold at 50 micrograms/mL. Combining long-term pioglitazone (10 micrograms/mL for 24 hours) and short-term insulin treatment resulted in an additive effect on 2-DOG uptake over a wide range of insulin concentrations (0.1 to 100 nmol/L) without the desensitization to 2-DOG uptake seen in other systems following long-term insulin administration. To determine the basis of the increased glucose uptake response, the level of specific mRNA and immunoreactive glucose transporter protein was determined. Northern and Western blot studies on glucose-treated cells (25 mmol/L) showed that glucose transporter mRNA and protein increased in parallel following treatment with either pioglitazone or insulin alone. The combination of insulin with pioglitazone resulted in an additive stimulation of glucose transporter mRNA and protein. In summary, pioglitazone stimulates hexose uptake both independently and in combination with insulin in BC3H-1 myocytes. These effects are largely accounted for by increases in glucose transporter mRNA and protein, indicating its potential efficacy in the treatment of non-insulin-dependent diabetes mellitus (NIDDM).(ABSTRACT TRUNCATED AT 250 WORDS)

Regulation of the GLUT1 glucose transporter in cultured myocytes: total number and subcellular distribution as determined by photoaffinity labelling.

We have used the impermeant photoaffinity label 2-N-4-(1-azi-2,2,2-trifluoroethyl)benzoyl-[2-3H] 1,3-bis-(D-mannos-4-yloxy)-2-propylamine (ATB-[2-3H]BMPA) to identify and quantify the glucose transporters on the surface of BC3H-1 cells, a continuously cultured skeletal-muscle cell line lacking the MyoD transcription factor required for cell fusion. ATB-[2-3H]BMPA was used in combination with immunoprecipitation of the GLUT1 glucose transporter, the only isoform expressed in these cells. The total cellular GLUT1 content was also determined by photolabelling and immunoprecipitation after cell permeabilization with digitonin (0.025%). In glucose-starved cells, 85% of the glucose transporters were present at the cell surface in the basal state, with little change in response to insulin (200 nM), correlating with lack of additional 2-deoxyglucose uptake in response to insulin. Feeding the cells with glucose (25 mM) for 24 h resulted in an 80% decrease in the total GLUT1 content relative to starved cells, of which only 25% were present on the cell surface. This was associated with an 85% decrease in 2-deoxyglucose uptake. In addition, acute stimulation of the fed cells with insulin or phorbol 12-myristate 13-acetate (PMA) led to an increase in GLUT1 at the cell surface, and, in correspondence, an increase in 2-deoxyglucose uptake by approx. 2- and 4-fold respectively. We conclude that exofacial photoaffinity labelling of glucose transporters with ATB-[2-3H]BMPA in the presence and absence of digitonin, followed by specific immunoprecipitation, provides an accurate measure of total and cell-surface glucose transporters in differentiated BC3H-1 muscle cells. This technique demonstrates that glucose pre-feeding (1) decreases the total number of GLUT1 and (2) redistributes the majority of the remaining transporters to an intracellular site, where they can now be translocated to the cell surface in response to insulin and PMA.