Changes in racial and ethnic disparities in glucose-lowering drug utilization and glycated haemoglobin A1c in US adults with diabetes: 2005-2018.

Abstract

To examine changes in racial and ethnic disparities in glucose-lowering drugs (GLD) use and glycated haemoglobin A1c in US adults with diabetes from 2005 to 2018. We conducted pooled cross-sectional analysis using data from the 2005-2018 Medical Expenditure Panel Surveys, and the 2005-2018 National Health and Nutrition Examination Survey. Individuals ≥18 years with diabetes were included. Racial and ethnic disparities were measured in (a) newer non-insulin GLD use; (b) insulin analogue use; (c) non-insulin GLDs adherence; (d) insulin adherence; and (e) glucose management, along with (f) the proportion of the disparities explained by potential contributing factors. From 2005 to 2018, racial and ethnic disparities persisted in newer GLD use, non-insulin GLDs adherence, insulin analogue use and glucose management. In 2018, compared with non-Hispanic white adults, non-Hispanic black, Hispanic and other race/ethnicity groups had lower rates of using newer GLDs (adjusted risk ratio: 0.44, 0.52, 0.64, respectively; p < .05 for all) and insulin analogues (adjusted risk ratio: 0.93, 0.89, 0.95, respectively; p < .05 for all except other groups), lower non-insulin GLD adherence (proportion of days covered: -4.5%, -5.6%, -4.3%, respectively; p < .05 for all), higher glycated haemoglobin A1c (0.29%, 0.32%, 0.02%, respectively; p < .05 for all except other group), and similar insulin adherences. Socioeconomic and health status were the main contributors to these disparities. Our findings provide evidence of racial and ethnic disparities in newer GLD use and quality of care in glucose management. Our study results can inform decision-makers of the status of racial and ethnic disparities and identify ways to reduce these disparities.