Differences in U.S. Rural-Urban Trends in Diabetes ABCS, 1999–2018

Objective: To examine changes and the relationships between rural-urban residence and diabetes management.

Research Design and Methods: Using National Health and Nutrition Examination Survey (1999-2018) data from 6,372 adults aged ≥18 years with self-reported diagnosed diabetes, we examined poor ABCS as A1c >9% [>75 mmol/mol], Blood pressure (BP) ≥140/90 mmHg, Cholesterol (non-HDL) ≥160 mg/dL [≥4.1 mmol/L], and current Smoking. We compared odds of urban vs rural residents (census tract population size ≥2500 considered urban, otherwise rural) with poor ABCS across time (1999-2006, 2007-2012, and 2013-2018), overall and by sociodemographic and clinical characteristics.

Results: Over 1999-2018, the proportion of U.S. adults with diabetes residing in rural areas ranged between 15% to 19.5%. In 1999-2006, there were no statistically significant rural-urban differences in poor ABCS. However, from 1999-2006 to 2013-2018, there were greater improvements for urban adults with diabetes than rural for BP≥140/90mmHg (relative OR: 0.8, 0.6-0.9) and non-HDL≥160mg/dL (≥4.1mmol/L) (relative OR: 0.6, 0.4-0.9). These differences remained statistically significant after adjusting for race/ethnicity, education, poverty levels, and clinical characteristics. Yet, over the 1999-2018 time period, minority race/ethnicity, lower education attainment, poverty, and lack of health insurance coverage were factors associated with poorer A, B, C, or S in urban compared to rural counterparts.

Conclusions: Over two decades, rural U.S. adults with diabetes have had less improvements in BP and cholesterol control. In addition, rural-urban differences exist across sociodemographic groups, suggesting that efforts to narrow this divide may need to address both socioeconomic and clinical aspects of care.