Racial Disparities in Type 2 Diabetes Mellitus

Purpose:Type 2 diabetes is a prevalent chronic disease of middle-aged and older adults. Particularly, about one in four older Americans have diabetes.  Diabetes is the fourth leading cause of death among people aged 45 to 64.  Racial/ethnicity disparities exist in diabetes care and outcomes. Non-Hispanic Blacks are more likely to develop the disease than other racial groups.  However, relatively little is known about the mechanisms underlying the racial differences in diabetes risk factors and the disease-disability pathways. Thus this study aims to investigate racial differences in diabetes-related biological indicators, self-management behaviors, and psychosocial factors.  

Methods:This study used data from middle-aged and older adults who responded to the 2004 core interviews of the U.S. nationally representative Health and Retirement Study (HRS) and the 2003 HRS diabetes-specific data.  Drawing on the disablement process model, risk factors of diabetes were identified, including biological factors (glycosylated hemoglobin value [HbA1c], body mass index [BMI], blood pressure, and early complications), self-management behaviors (exercise, diet, medication adherence, and blood glucose self-monitoring), and psychosocial factors (perceived control, diabetes-specific self-efficacy, depressive symptoms, perceived social support, and coping skills). Analysis of variance (ANOVA) was conducted to examine racial differences in these risk factors and functional limitations as well as medical care access and use across racial groups.

Results:Among 1,572 respondents diagnosed with type 2 diabetes in 2003, 72.9% were non-Hispanic White, 17.2% non-Hispanic Black, and 9.9% Hispanic. Compared to non-Hispanic Whites, non-Hispanic Blacks self-reported higher BMI, worse blood pressure, and more limitations in activities of daily living.  Both non-Hispanic Blacks and Hispanics had significantly higher HbA1c levels than non-Hispanic Whites.  No racial difference was observed in self-management behaviors except that non-Hispanic Whites reported higher levels of medication adherence.  Although Hispanics reported higher levels of diabetes-specific self-efficacy and perceived social support, they had significantly higher scores on depressive symptoms, but lower scores on perceived self-control and diabetes coping status than the other two groups. In addition, Hispanics were less likely to be covered by health insurance and to have coverage for prescription drugs when first diagnosed with diabetes.  Also they were less likely to see health care providers for diabetes and/or other reasons.

Implications: The study results are broadly consistent with much of the literature on racial disparities in diabetes risks and outcomes. Particularly, this study identified racial disparities in diabetes-related risk factors. Non-Hispanic Blacks have a greater risk of developing diabetes with worse biological indicators, and Hispanics are in relatively weaker psychosocial status to deal with diabetes.  The study shed light on the need for social workers and health care providers involved with diabetes care to address the unique needs of racial/ethnicity groups. For non-Hispanic Blacks, it is important to help deal with health challenge and decreased functioning associated with diabetes. For Hispanics, it may be important to increase and strengthen their coping strategies, perceived control, and positive mood. Further research is needed to understand how risk factors differently affect diabetes-disability pathways and functional health change across racial/ethnicity groups.