Monday, Oct 19 at noon, 6050 ISR
Heisler, Michele, Jessica Faul, Rodney Hayward, Kenneth M. Langa, Caroline Blaum, and David Weir. 2007. "Mechanisms for Racial and Ethnic Disparities in Glycemic Control in Middle-aged and Older Americans in the Health and Retirement Study." Archives of Internal Medicine, 167(17): 1853-1860.
Background Mechanisms for racial/ethnic disparities in glycemic control are poorly understood.
Methods A nationally representative sample of 1901 respondents 55 years or older with diabetes mellitus completed a mailed survey in 2003; 1233 respondents completed valid at-home hemoglobin A1c (HbA1c) kits. We constructed multivariate regression models with survey weights to examine racial/ethnic differences in HbA1c control and to explore the association of HbA1c level with sociodemographic and clinical factors, access to and quality of diabetes health care, and self-management behaviors and attitudes.
Results There were no significant racial/ethnic differences in HbA1c levels in respondents not taking antihyperglycemic medications. In 1034 respondents taking medications, the mean HbA1c value (expressed as percentage of total hemoglobin) was 8.07% in black respondents and 8.14% in Latino respondents compared with 7.22% in white respondents (P < .001). Black respondents had worse medication adherence than white respondents, and Latino respondents had more diabetes-specific emotional distress (P < .001). Adjusting for hypothesized mechanisms accounted for 14.0% of the higher HbA1c levels in black respondents and 19.0% in Latinos, with the full model explaining 22.0% of the variance. Besides black and Latino ethnicity, only insulin use (P < .001), age younger than 65 years (P = .007), longer diabetes duration (P = .004), and lower self-reported medication adherence (P = .04) were independently associated with higher HbA1c levels.
Conclusions Latino and African American respondents had worse glycemic control than white respondents. Socioeconomic, clinical, health care, and self-management measures explained approximately a fifth of the HbA1c differences. One potentially modifiable factor for which there were racial disparities—medication adherence—was among the most significant independent predictors of glycemic control.