OBJECTIVE—To evaluate health care access and utilization and health status and outcomes for type 2 diabetic patients according to race and ethnicity and to determine whether health status is influenced by health care access and utilization.

RESEARCH DESIGN AND METHODS—National samples of Caucasians, African-Americans, and Mexican-Americans were studied in the third National Health and Nutrition Examination Survey. Information on medical history and treatment of diabetes, health care access and utilization, and health status and outcomes was obtained by structured questionnaires and by clinical and laboratory assessments.

RESULTS—Almost all patients in each race and ethnic group had one primary source of ambulatory medical care (92–97%), saw one physician at this source (83–92%), and had at least semiannual physician visits (83–90%). Almost all patients ≥65 years of age had health insurance (99–100%), and for those patients <65 years of age, Caucasians (91%) and African-Americans (89%) had higher rates of coverage than Mexican-Americans (66%). Rates of treatment with insulin or oral agents (71–78%), eye examination in the previous year (61–70%), blood pressure check in the previous 6 months (83–89%), and the proportion of hypertension that was diagnosed (84–91%) were similar for each race and ethnic group. Lower proportions of African-Americans and Mexican-Americans self-monitored their blood glucose (insulin-treated, 27 vs. 44% of Caucasians), had their cholesterol checked (62–68 vs. 81%), and had their dyslipidemia diagnosed (45 vs. 58%). African-American and Mexican-American patients had a somewhat higher proportion than Caucasian patients, with HbA1c ≥7% (58–66 vs. 55%), blood pressure ≥140/90 mmHg among those with diagnosed hypertension (60–65 vs. 55%), and clinical proteinuria (11–14 vs. 5%). In contrast, they had better levels of total cholesterol (≥240 mg/dl) (28–30 vs. 34%) and HDL cholesterol (≥45 mg/dl) (46–59 vs. 38%), and African-American and Mexican-American men were less overweight than Caucasian men (BMI ≥30) (34–37 vs. 44%), although the opposite was true for women. LDL cholesterol levels and the proportion of patients who smoked cigarettes or were hospitalized in the past year were similar among all three groups. In logistic regression analysis, there was little evidence that levels of blood glucose, blood pressure, lipids, or albuminuria were associated with access to or utilization of health care or with socioeconomic status.

CONCLUSIONS—There are some differences by race and ethnicity in health care access and utilization and in health status and outcomes for adults with type 2 diabetes. However, the magnitude of these differences pale in comparison with the suboptimal health status of all three race and ethnic groups relative to established treatment goals. Health status does not appear to be influenced by access to health care.

In the U.S., there is considerable variation by race and ethnicity in health care access and utilization for a number of diseases and conditions. For example, surgery rates were substantially lower for African-American patients with resectable nonsmall-cell lung cancer than for Caucasian patients, which accounted for the lower survival rate of the African-American patients (1). African-American and Hispanic women were less likely to have mammograms and more likely to present with late-stage breast cancer than Caucasian women (2,3). The use of antiretroviral therapy was significantly less common for African-Americans and Latinos in a national sample of people with AIDS (4). African Americans were less likely to have cardiac procedures, including reperfusion therapy for myocardial infarction, cardiac catheterization, coronary artery bypass graft surgery, and percutaneous transluminal coronary angioplasty (5,6).

For diabetic patients, such variation in health care access and utilization has not been documented. Nevertheless, considerable attention has been garnered by the concept that access and utilization are major determinants of quality of care and health outcomes in diabetes. It is widely believed that diabetes care in the U.S. is suboptimal and that patients with diabetes are not receiving the care known to be beneficial. For example, the Diabetes Quality Improvement Project (DQIP), sponsored by a number of organizations with interest in diabetes, was created to assess the level of care provided to patients with diabetes and to improve the accountability of the health system (7).

It is well established that racial and ethnic differences exist in end-stage clinical outcomes for diabetic patients. Microvascular complications of the eyes, nerves, and kidneys and lower extremity amputations are more common in African-Americans, Hispanic Americans, and Native Americans with diabetes than in non-Hispanic Caucasian patients (815). However, these end-stage complications result only after a long duration of diabetes and thus occur in patients who were diagnosed and received much of their medical care many years ago. The current contribution of the health care system to these racial and ethnic differences in adverse health outcomes versus the contributions of patient self-care practices and inherent biological and genetic factors is yet undetermined.

To investigate these issues, we analyzed data from the third National Health and Nutrition Examination Survey (NHANES III), in which questionnaire, clinical, and laboratory data on health care access, utilization, and medical outcomes were obtained for a representative sample of type 2 diabetic adults. The outcomes studied were those that are expected to be influenced by recent medical care, such as hyperglycemia, albuminuria, hypertension, and dyslipidemia.

NHANES III was conducted from 1988 to 1994 and included a stratified probability sample of the civilian noninstitutionalized U.S. population, with oversampling of African-Americans and Mexican-Americans. The design and conduct of the survey has been described (16). Participants were interviewed in their homes and were given a standardized set of examinations and laboratory measurements in an examination center. There were 16,993 participants ≥25 years of age, 1,608 of whom reported that they had been diagnosed with diabetes by a physician before the survey. Women with diabetes diagnosed only during pregnancy (n = 105) and subjects with type 1 diabetes, defined as those <30 years of age at diagnosis who had continuous insulin use since diagnosis of diabetes (n = 23), were eliminated from analysis. The remaining 1,480 subjects were considered to have type 2 diabetes and included 590 non-Hispanic Caucasians, 405 non-Hispanic African-Americans, 450 Mexican-Americans, and 35 individuals of other races and ethnicities.

Information on sociodemographic and lifestyle characteristics, diabetes treatment, medical history, and health care utilization was obtained by structured questionnaires. Measurements of height, weight, HbA1c, urine albumin and creatinine, blood pressure, and lipids were made during a separate clinical examination in which 88.2% of the interviewed subjects participated (n = 1,306) (17). Those who were examined did not differ from those who were not examined (16). Measures of functional status and quality of life were not obtained in NHANES III. Hypertension was defined as systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg or taking antihypertensive medication. Dyslipidemia was defined as LDL cholesterol ≥130 mg/dl or treatment with prescribed diet or medication. Definitions of treatment goals and abnormal values for HbA1c, proteinuria, obesity, blood pressure, and blood lipids are those recommended by professional scientific organizations (1821).

Statistical analyses were carried out using SAS (Cary, NC) with appropriate sampling weights to adjust for the stratified sample design. Standard errors were calculated and tests of statistical significance and logistic regression were performed using SUDAAN (Research Triangle Institute, Research Triangle Park, NC). Logistic regression with usual source of health care, number of physician visits, and any or private health insurance as independent variables was conducted for each race and ethnic group to examine whether there was any influence of these health care variables on health status and outcomes. Education and income were included as independent variables in additional models to determine whether there was any influence of socioeconomic status.

Of all patients, 74.4% were non-Hispanic Caucasian, 15.0% were non-Hispanic African-American, 5.8% were Mexican-American, and 4.8% were of other race and ethnicity. Table 1 compares characteristics of the three main race and ethnic groups. Non-Hispanic Caucasians were older and greater proportions of them were male, had completed high school, and had family income ≥$20,000. Caucasian men were heavier than African-American and Mexican-American men, and African-American women were heavier than Caucasian and Mexican-American women. Non-Hispanic African-Americans had a longer duration since diagnosis of diabetes and a greater proportion had hypertension. Mexican-Americans had the lowest rates of hypertension and dyslipidemia. ### Health care access and utilization Health care access and utilization are shown in Table 2. Almost all patients in each race and ethnic group had one primary source of ambulatory medical care, described as a physician’s office, clinic, or health center. Most of these patients consistently saw one specific physician at this source; 83–90% had at least semi-annual visits, and 62–68% had at least quarterly visits. Almost all patients ≥65 years of age had health insurance of some type (private insurance, Medicare, Medicaid, Champus, or Veterans Administration). However, for those patients <65 years of age, Caucasians and African-Americans had higher rates of coverage than Mexican-Americans. A larger proportion of African-Americans was treated with insulin, but a smaller proportion was treated using oral agents, such that the rates of pharmacological treatment were similar for each race and ethnic group (Table 2). Approximately half of the patients treated with insulin took two or more injections per day; the rates in African-Americans and Mexican-Americans were lower than those for Caucasians. Self-monitoring of blood glucose was rare among patients who were not treated with insulin. Among insulin-treated patients, a lower proportion of African-Americans and Mexican-Americans self-monitored their blood glucose than Caucasians. About two-thirds of patients had a dilated eye examination during the previous year, and almost all patients had their blood pressure checked within the previous 6 months. Differences by race and ethnicity in these procedures were not statistically significant. Clinical hypertension was present in 66% of Caucasian patients, 71% of African-Americans, and 54% of Mexican-Americans (Table 1). Of those with hypertension, most were being treated with antihypertensive medication (Table 2). The proportion of hypertension that was untreated or undiagnosed was higher in Mexican-Americans (29%) than in Caucasians (17%) or African-Americans (16%). Dyslipidemia was present in 65% of Caucasians, 62% of African-Americans, and 51% of Mexican-Americans (Table 1). Much of the dyslipidemia was untreated by either diet or medication or was undiagnosed in all three race and ethnic groups (Table 2). ### Health status and outcomes Health status and outcome measures that were expected to be influenced by recent medical care are shown in Table 3. Although some measures were more severe in African-Americans and Mexican-Americans, these differences were often small or not statistically significant. African-Americans and Mexican-Americans had somewhat higher proportions of HbA1c ≥7%, clinical proteinuria, and blood pressure ≥140/90 mmHg among those with diagnosed hypertension. In contrast, they had better levels of total cholesterol and HDL cholesterol than Caucasians, and African-American and Mexican-American men were less overweight than Caucasian men (although the opposite was true for women). More than half of each group had an HbA1c value >7.0%, the recommended treatment goal for blood glucose control, and one-third of each group had either microalbuminuria or clinical proteinuria (Table 3). Of those whose hypertension had been diagnosed before the survey, more than half of each race and ethnic group were not controlled to the level of <140/90 mmHg, even though 70–80% of these individuals were taking antihypertensive medication. An aggressive approach, including dietary changes and drug therapy, is recommended for diabetic patients who have LDL cholesterol values ≥130 mg/dl. In NHANES III, of those who had previously been diagnosed with dyslipidemia, only approximately one-third had LDL cholesterol <130 mg/dl, although most were being treated with diet and/or medication. The percentage distributions for total cholesterol, HDL cholesterol, triglycerides, and LDL cholesterol are shown in Table 3. Large proportions of each race and ethnic group had levels that were above normal for each lipid variable. Elevated levels of lipoprotein(a) were found more often in African-Americans than in Caucasians and Mexican-Americans. Rates of homocysteinuria, cigarette smoking, and hospitalization in the previous year were similar among the three groups. The association of health outcomes, (i.e., good blood glucose control [HbA1c <7.0], absence of albuminuria [albumin-to-creatinine ratio <30 mg/g], controlled hypertension among those known to have hypertension [<140/90 mmHg], and controlled dyslipidemia among those known to have dyslipidemia [LDL cholesterol <130 mg/dl]) and measures of access to health care were examined in logistic regression analyses separately for Caucasians, African-Americans, and Mexican-Americans. With few exceptions, the outcomes for each racial and ethnic group were not significantly associated with having a primary source of ambulatory medical care, the number of physician visits per year, having any type of health insurance, or having private insurance. The exceptions included the following features. For Caucasians, the 96.7% who had a usual source of ambulatory medical care were more likely to have HbA1c <7.0% than the 3.3% without a usual source of care (odds ratio [OR] 10.4, 95% CI 1.3–84.2). Hypertensive African-Americans with six or more physician visits in the previous year were more likely to have blood pressure <140/90 mmHg than those with less than six visits (OR 1.5, CI 1.2–4.8). The 93% of African-Americans with any type of health insurance were more likely than the 7% without insurance to have HbA1c <7.0% (OR 3.7, CI 1.1–12.5) and to have albumin-to-creatinine ratio <30 mg/g (2.7, 1.1–6.5). African-Americans and Mexican-Americans with private health insurance (56 and 45% of these groups, respectively) were more likely to have albumin-to-creatinine ratio <30 mg/g (OR 1.6, CI 1.1–2.4 and OR 2.1, CI 1.2–3.3, respectively). Because of the many logistic regressions performed and the wide CIs, the clinical and statistical significance of these few exceptions should be considered with reservation. There was no association of socioeconomic status, measured by levels of education and income, with blood glucose control, hypertension control, lipid control, or albuminuria in Caucasians, African-Americans, or Mexican-Americans, with only one exception: Mexican-Americans with a high school education or more were twice as likely to have normoalbuminuria as those with less than a high school education (OR 2.1, CI 1.1–4.1). These data indicate that there are some differences among Caucasians, African-Americans, and Mexican-Americans in health care access and utilization and in health status and outcome measures that are influenced by recent medical care, such as hyperglycemia, albuminuria, hypertension, and dyslipidemia. However, many of the differences are small or are not statistically significant. More importantly, the magnitude of the differences pale in comparison with the suboptimal health status of all three race and ethnic groups relative to current treatment goals for blood glucose, blood pressure, lipids, and albuminuria. In each race and ethnic group, there were high rates of health care access and utilization, screening for diabetes complications, and treatment of hyperglycemia, hypertension, and dyslipidemia. Nevertheless, in each group, glycemic control was poor; many patients were obese and had albuminuria, and much of the hypertension and dyslipidemia was not controlled. One-fourth of patients had to be hospitalized in the previous year, and one-fifth of patients smoked cigarettes. In logistic regression, there was little evidence in any of the race and ethnic groups that health status and outcomes were influenced by access to or utilization of health care or by socioeconomic status. As previously discussed (17), it is likely that health outcomes for patients with diabetes are determined by multiple factors, including intractability of diabetes to current therapies, patient self-care practices, physician medical care practices, and characteristics of U.S. health care systems, rather than by the race and ethnicity of diabetic patients. Only a few previous studies have examined race and ethnic differences in health care for diabetes. For Medicare patients in 1993, rates for quality of care measures were low for all patients. There were small differences between African-Americans and Caucasians in health perception, but not in rates of diabetes complications or ability to perform activities of daily living. African-Americans less frequently had data recorded in their insurance claims showing that HbA1c was measured, an ophthalmic visit was made, lipids were measured, and influenza vaccination was administered, but rates were not different for mammograms or hospitalization follow-up (22). In another study of Medicare records in 1992, race was not a predictor of expenditures for diabetes care (23). In a Michigan health maintenance organization (HMO) in 1991, African-Americans had higher HbA1c and creatinine values, but both African-American and Caucasian patients infrequently received the medical care recommended by the American Diabetes Association (ADA) (24). In a California HMO in 1992, an eight-point prevention score reflecting ADA guidelines for care and rates of diabetes complications did not differ by race (25). The literature is replete with studies showing that marked benefits to diabetic patients can accrue from reducing risk factors for diabetes complications. Improved glycemic control is associated with long-term health benefits such as decreased incidence of retinopathy, neuropathy, nephropathy, and other end-stage complications (26,27). It is also associated with substantial short-term improvements in quality of life, symptom distress, physical functioning, and economic benefits, including higher retained employment and less absenteeism (28). In contrast, medical care charges increase significantly for increases in HbA1c levels >7%, suggesting that investment in clinical systems to improve diabetes care may benefit both payers and patients (29). The benefits of decreasing blood pressure and lipids are well recognized and include reductions in the risk of micro- and macrovascular disease and death (3032). Socioeconomic status does not appear to be an important determinant of diabetes complications. Among Hispanics and Anglos in San Antonio, Texas, complications of diabetes were not related to socioeconomic status (33). No association of glycemic control with income or education was found in Caucasians, African-Americans, or Mexican-Americans in NHANES III (34). Table 1 — Characteristics of type 2 diabetic adults, according to race and ethnicity Non-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American Median age (years) 63.4 59.5* 56.1 Median duration since diabetes diagnosis (years) 6.4 7.6 5.4 Men 46.0 37.3 38.7 High school education or more 61.1 42.7 23.1 Family income ≥$20,000 58.6 31.5 35.0
Mean BMI (kg/m2
Men 29.8 28.3* 29.3
Women 30.8 32.6 31.0
Hypertension 65.9 71.4 53.8
Dyslipidemia 65.3 62.2 51.2*
Non-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American
Median age (years) 63.4 59.5* 56.1
Median duration since diabetes diagnosis (years) 6.4 7.6 5.4
Men 46.0 37.3 38.7
High school education or more 61.1 42.7 23.1
Family income ≥\$20,000 58.6 31.5 35.0
Mean BMI (kg/m2
Men 29.8 28.3* 29.3
Women 30.8 32.6 31.0
Hypertension 65.9 71.4 53.8
Dyslipidemia 65.3 62.2 51.2*

Data are %, unless otherwise indicated.

*

P < 0.01

P < 0.001

P < 0.05 compared with non-Hispanic Caucasians.

Table 2 —

Health care access for type 2 diabetic adults

Health care accessNon-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American
One usual source of ambulatory medical care 96.7 93.9 91.9
Sees one primary physician at this source 92.4 88.2 83.1
Two or more physician visits in past 12 months 90.3 86.6 83.2
Health insurance
Age 25–64 years 91.4 88.7 65.9*
Age ≥65 years 99.8 100.0 99.7
Private health insurance
Age 25–64 years 80.8 62.9* 46.2*
Age ≥65 years 80.3 42.9* 40.9*
Diabetes therapy
Insulin 25.7 41.6 25.3
Oral agents 45.7 36.5 50.3
Diet alone 28.6 21.9 24.4
Insulin treated, ≥2 injections per day 60.4 42.3 48.2
Self-monitors blood glucose at least once per day
Not insulin-treated 5.8 3.9 2.4
Insulin-treated 44.2 26.7 27.3
Eye examination in the past year 65.3 70.1 60.8
Blood pressure checked in the past 6 months 88.4 89.4 83.4
Cholesterol checked 80.8 68.1* 61.8*
Hypertension
Previously diagnosed, taking antihypertensive medication 83.1 84.1 71.3
Previously diagnosed, not taking antihypertension medication 6.4 6.8 12.8
Undiagnosed 10.5 9.1 15.9
Dyslipidemia
Previously diagnosed, treated with diet or medication 52.3 40.3 40.6
Previously diagnosed, not treated with diet or medication 6.2 4.5 4.3
Undiagnosed 41.6 55.3 55.1
Health care accessNon-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American
One usual source of ambulatory medical care 96.7 93.9 91.9
Sees one primary physician at this source 92.4 88.2 83.1
Two or more physician visits in past 12 months 90.3 86.6 83.2
Health insurance
Age 25–64 years 91.4 88.7 65.9*
Age ≥65 years 99.8 100.0 99.7
Private health insurance
Age 25–64 years 80.8 62.9* 46.2*
Age ≥65 years 80.3 42.9* 40.9*
Diabetes therapy
Insulin 25.7 41.6 25.3
Oral agents 45.7 36.5 50.3
Diet alone 28.6 21.9 24.4
Insulin treated, ≥2 injections per day 60.4 42.3 48.2
Self-monitors blood glucose at least once per day
Not insulin-treated 5.8 3.9 2.4
Insulin-treated 44.2 26.7 27.3
Eye examination in the past year 65.3 70.1 60.8
Blood pressure checked in the past 6 months 88.4 89.4 83.4
Cholesterol checked 80.8 68.1* 61.8*
Hypertension
Previously diagnosed, taking antihypertensive medication 83.1 84.1 71.3
Previously diagnosed, not taking antihypertension medication 6.4 6.8 12.8
Undiagnosed 10.5 9.1 15.9
Dyslipidemia
Previously diagnosed, treated with diet or medication 52.3 40.3 40.6
Previously diagnosed, not treated with diet or medication 6.2 4.5 4.3
Undiagnosed 41.6 55.3 55.1

Data are %. Sample sizes for hypertension (n = 864) and dyslipidemia (n = 627) exclude subjects who do not have these conditions; dyslipidemia data also exclude subjects with triglyceride levels ≥400 mg/dl for whom the Friedewald equation to compute LDL cholesterol is not valid.

*

P < 0.001

P < 0.01

P < 0.05 compared with non-Hispanic Caucasians.

Table 3 —

Health status and outcomes for type 2 diabetic adults

Health care outcomeNon-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American
HbA1c ≥7.0% 55.1 58.2 65.5*
BMI ≥30 kg/m2
Men 43.5 34.3 37.0
Women 45.5 53.7 48.2
Microalbuminuria 29.6 27.3 26.3
Clinical proteinuria 5.2 13.6 11.2*
Previously diagnosed hypertension
Blood pressure <140/90 mmHg 45.2 39.6 34.7
Blood pressure ≥140/90 mmHg 54.8 60.4 65.3
Previously diagnosed dyslipidemia
LDL cholesterol <130 mg/dl 35.4 23.9 37.9
LDL cholesterol ≥130 mg/dl 64.6 76.1 62.1
Serum total cholesterol (mg/dl)
<200 31.1 35.7 38.1
200–239 34.5 33.9 33.8
≥240 34.4 30.4 28.1
HDL cholesterol (mg/dl)
<35 28.9 13.0 20.1
35–45 32.7 28.0 33.9
>45 38.4 59.0 46.0
Triglyceride (mg/dl)
<200 57.1 74.8 57.3
200–399 30.8 19.7* 27.9
≥400 12.1 5.5 14.8
LDL cholesterol (mg/dl)
<100 15.4 19.6 21.1
100–129 32.8 24.9 36.4
130–159 30.6 28.6 26.6
≥160 21.2 26.9 15.9
Lipoprotein(a) >30 mg/dl 20.1 58.8 21.3
Homocysteine >15 μmol/l 13.9 11.5 6.5
Cigarette smoker 18.0 23.9 17.7
Hospitalized in past 12 months 27.1 27.9 22.6
Health care outcomeNon-Hispanic CaucasianNon-Hispanic African-AmericanMexican-American
HbA1c ≥7.0% 55.1 58.2 65.5*
BMI ≥30 kg/m2
Men 43.5 34.3 37.0
Women 45.5 53.7 48.2
Microalbuminuria 29.6 27.3 26.3
Clinical proteinuria 5.2 13.6 11.2*
Previously diagnosed hypertension
Blood pressure <140/90 mmHg 45.2 39.6 34.7
Blood pressure ≥140/90 mmHg 54.8 60.4 65.3
Previously diagnosed dyslipidemia
LDL cholesterol <130 mg/dl 35.4 23.9 37.9
LDL cholesterol ≥130 mg/dl 64.6 76.1 62.1
Serum total cholesterol (mg/dl)
<200 31.1 35.7 38.1
200–239 34.5 33.9 33.8
≥240 34.4 30.4 28.1
HDL cholesterol (mg/dl)
<35 28.9 13.0 20.1
35–45 32.7 28.0 33.9
>45 38.4 59.0 46.0
Triglyceride (mg/dl)
<200 57.1 74.8 57.3
200–399 30.8 19.7* 27.9
≥400 12.1 5.5 14.8
LDL cholesterol (mg/dl)
<100 15.4 19.6 21.1
100–129 32.8 24.9 36.4
130–159 30.6 28.6 26.6
≥160 21.2 26.9 15.9
Lipoprotein(a) >30 mg/dl 20.1 58.8 21.3
Homocysteine >15 μmol/l 13.9 11.5 6.5
Cigarette smoker 18.0 23.9 17.7
Hospitalized in past 12 months 27.1 27.9 22.6

Data are %. The upper limit of normal for HbA1c in the assay system is 6.1%, defined as the mean + 2 SD (5.27 + 0.85%) for the group of people with fasting plasma glucose <110 mg/dl and 2-h postchallenge glucose <140 mg/dl. Samples sizes for previously diagnosed hypertension (n = 618) and previously diagnosed dyslipidemia (n = 302) exclude subjects who have not been diagnosed with these conditions; dyslipidemia data also exclude subjects with triglyceride levels ≥400 mg/dl for whom the Friedewald equation to compute LDL cholesterol is not valid.

*

P < 0.01

P < 0.001

P < 0.05 compared with non-Hispanic Caucasians.

1.
Bach PB, Cramer LD, Warren JL, Begg CB: Racial differences in the treatment of early-stage lung cancer.
N Engl J Med
341
:
1198
–1205,
1999
2.
Yood MU, Johnson CC, Blount A, Abrams J, Wolman E, McCarthy BD, Raju U, Nathanson DS, Worsham M, Wolman SR: Race and differences in breast cancer survival in a managed care population.
J Natl Cancer Inst
91
:
1487
–91,
1999
3.
Frost FJ, Tollestrup K, Trinkaus KM, Rodgers D, Kunde T, Petersen HV, Stidley CA: Mammography screening and breast cancer tumor size in female members of a managed care organization.
Cancer Epidemiol Biomarkers Prev
7
:
585
–9,
1998
4.
Shapiro MF, Morton SC, McCaffrey DF, Senterfitt JW, Fleishman JA, Perlman JF, Athey LA, Keesey JW, Goldman DP, Berry SH, Bozzette SA, for the HCSUS Consortium: Variations in the care of HIV-infected adults in the United States.
J Am Med Assn
281
:
2305
–15,
1999
5.
Canto JG, Allison JJ, Kiefe CI, Fincher C, Farmer R, Sekar P, Person S, Weissman NW: Relation of race and sex to the use of reperfusion therapy in Medicare beneficiaries with acute myocardial infarction.
N Engl J Med
342
:
1094
–1100,
2000
6.
Sheifer SE, Escarce JJ, Schulman KA: Race and sex differences in the management of coronary artery disease.
Am Heart J
139
:
848
–857,
2000
7.
Diabetes Quality Improvement Project [article online],
1998
. Available from http://www.diabetes.org/dqip.asp. Accessed20 July
2000
.
8.
Harris MI, Klein R, Cowie CC, Rowland M, Byrd-Holt DD: Is the risk of diabetic retinopathy greater in non-Hispanic African-Americans and Mexican-Americans than in non-Hispanic Caucasians with type 2 diabetes?: a U.S. population study.
Diabetes Care
21
:
1230
–1235,
1998
9.
Haffner SM, Fong D, Stern MP, Pugh JA, Hazuda HP, Patterson JK, Van Heuven WAJ, Klein R: Diabetic retinopathy in Mexican-Americans and non-Hispanic whites.
Diabetes
37
:
878
–884,
1988
10.
Franklin GM, Kahn LB, Baxter J, Marshall JA, Hamman RF: Sensory neuropathy in noninsulin-dependent diabetes mellitus: the San Luis Valley Diabetes Study.
Am J Epidemiol
131
:
633
–643,
1990
11.
Cowie CC, Port FK, Wolfe RA, Savage PJ, Moll PP, Hawthorne VM: Disparities in incidence of diabetic end-stage renal disease by race and type of diabetes.
N Engl J Med
321
:
1074
–79,
1989
12.
Haffner SM, Mitchell BD, Pugh JA, Stern MP, Kozlowski MK, Hazuda HP, Patterson JK, Klein R: Proteinuria in Mexican-Americans and non-Hispanic Caucasians with NIDDM.
Diabetes Care
12
:
530
–536,
1989
13.
Nelson RG, Morgenstern H, Bennett PH: An epidemic of proteinuria in Pima Indians with type 2 diabetes mellitus.
Kidney Int
54
:
2081
–2088,
1998
14.
Resnick HE, Valsania P, Phillips CL: Diabetes mellitus and nontraumatic lower extremity amputation in African-American and Caucasian Americans: the National Health and Nutrition Examination Survey Epidemiologic Follow-up Study, 1971–1992.
Arch Intern Med
159
:
2470
–2475,
1999
15.
Lavery LA, van Houtum WH, Ashry HP, Armstrong DG, Pugh JA: Diabetes-related lower-extremity amputations disproportionately affect African-Americans and Mexican-Americans.
South Med J
92
:
593
–599,
1999
16.
Harris MI, Flegal KM, Cowie CC, Eberhardt MS, Goldstein DE, Little RR, Wiedmeyer HM, Byrd-Holt DD: Prevalence of diabetes, impaired fasting glucose, and impaired glucose tolerance in U.S. adults: the Third National Health and Nutrition Examination Survey, 1988–94.
Diabetes Care
21
:
518
–524,
1998
17.
Harris MI: Health care and health status and outcomes for patients with type 2 diabetes.
Diabetes Care
23
:
754
–758,
2000
18.
American Diabetes Association: Standards of medical care for patients with diabetes mellitus (Position Statement).
Diabetes Care
23 (Suppl. 1)
:
S32
–S42,
2000
19.
Joint National Committee: The fifth report of the Joint National Committee on Detection.
Arch Intern Med
153
:
154
–183,
1993
20.
National Cholesterol Education Program: Second report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel II).
Circulation
89
:
1333
–1445,
1994
21.
Bennett PH, Haffner S, Kasiske BL, Keane WF, Mogensen CE, Parving HH, Steffes MW, Striker GE: Screening and management of microalbuminuria in patients with diabetes mellitus: recommendation to the Scientific Advisory Board of the National Kidney Foundation.
Am J Kidney Dis
25
:
107
–112,
1995
22.
Chin MH, Zhang JX, Merrell K: Diabetes in the African-American Medicare population: morbidity, quality of care, and resource utilization.
Diabetes Care
21
:
1090
–1095,
1998
23.
Krop JS, Powe NR, Weller WE, Shaffer TJ, Saudek CD, Anderson GF: Patterns of expenditures and use of services among older adults with diabetes: implications for the transition to capitated managed care.
Diabetes Care
21
:
747
–752,
1998
24.
Wisdom K, Fryzek JP, Havstad SL, Anderson RM, Dreiling MC, Tilley BC: Comparison of laboratory test frequency and test results between African-Americans and Caucasians with diabetes: opportunity for improvement: findings from a large urban health maintenance organization.
Diabetes Care
20
:
971
–977,
1997
25.
Martin TL, Selby JV, Zhang D: Physician and patients prevention practices in NIDDM in a large urban managed-care organization.
Diabetes Care
18
:
124
–1132,
1995
26.
Diabetes Control and Complications Trial Research Group: The effect of intensive treatment of diabetes on the development and progression of long-term complications in insulin-dependent diabetes mellitus.
N Engl J Med
329
:
977
–986,
1993
27.
U.K. Prospective Diabetes Study (UKPDS) Group: Intensive blood-glucose control with sulphonylureas or insulin compared with conventional treatment and risk of complications in patients with type 2 diabetes (UKPDS 33).
Lancet
352
:
837
–853,
1998
28.
Testa MA, Simonson DC: Health economic benefits and quality of life during improved glycemic control in patients with type 2 diabetes mellitus: a randomized, controlled, double-blind trial.
JAMA
280
:
1490
–1496,
1998
29.
Gilmer TP, O’Connor PJ, Manning WG, Rush WA: The cost to health plans of poor glycemic control.
Diabetes Care
20
:
1847
–1853,
1997
30.
U.K. Prospective Diabetes Study (UKPDS) Group: Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes (UKPDS 38).
Br Med J
317
:
703
–713,
1998
31.
U.K. Prospective Diabetes Study (UKPDS) Group: Efficacy of atenolol and captopril in reducing risk of macrovascular and microvascular complications in type 2 diabetes (UKPDS 39).
Br Med J
317
:
713
–720,
1998
32.
Haffner S: Management of dyslipidemia in adults with diabetes.
Diabetes Care
21
:
160
–178,
1998
33.
Haffner SM, Hazuda HP, Stern MP, Patterson JK, Van Heuven WAJ, Fong D: Effect of socioeconomic status on hyperglycemia and retinopathy levels in Mexican-Americans with NIDDM.
Diabetes Care
12
:
128
–134,
1989
34.
Harris MI, Eastman RC, Cowie CC, Flegal KM, Eberhardt MS: Racial and ethnic differences in glycemic control of adults with type 2 diabetes.
Diabetes Care
22
:
403
–408,
1999

Address correspondence and reprint requests to Dr. Maureen I. Harris, NIDDK/NIH, 6707 Democracy Blvd., Room 695, MSC5460, Bethesda, MD 20892. E-mail: mh63q@nih.gov.

Received for publication 27 July 2000 and accepted in revised form 30 November 2000.

A table elsewhere in this issue shows Système International (SI) units and conversion factors for many substances.