Primary Submission Category: Health care/services
Community Health Centers: An Analysis of Racial and Ethnic Disparities in Cardiometabolic Health
Authors: Brittany Alosi David Curtis
Presenting Author: Brittany Alosi*
Diabetes prevalence has increased in the US in recent decades, with socially marginalized racial and ethnic groups disproportionately affected (Cheng, et al., 2019). In 2018, the age-adjusted percentage of adults with diabetes was 12.5% for Black and Hispanic Americans compared to 7.8% for Whites. Similarly, for Black relative to White Americans, hypertension is more common (32.8% vs. 24%) and more likely uncontrolled when diagnosed (National Health Interview Survey, 2018). Diabetes and hypertension, in turn, increase mortality risk, especially when uncontrolled (Nwaneri, et al., 2013; Kung, et al., 2015). Racial/ethnic disparities in the prevalence and control of cardiometabolic conditions therefore contribute to Black-White disparities in mortality from diabetes and from heart disease; Hispanic Americans relative to Whites also have higher mortality from diabetes but lower from heart disease (Murphy, et al., 2018). Improving prevention and management of cardiometabolic conditions for Black and Hispanic Americans is essential to reduce racial/ethnic disparities in mortality.
The US Department of Health and Human Services has the elimination of health disparities as a foundational principle (Healthy People 2030), with the Community Health Center (CHC) program being an important part of this federal strategic effort (NACHC, 2015; Geiger, 2005). CHCs are located in medically underserved areas where they serve a racially and ethnically diverse, low-income population. For many of their patients, 34% of whom are uninsured, CHCs represent the only source of primary care (Shin, et al., 2013).
CHCs currently serve over 30 million patients across the United States, an overwhelming percentage of whom are poor and historically underserved (BPHC 2023). Nearly 72% of patients are living below the federal poverty level (FPL), with another 14% between 101-150% FPL and 7% between 151-200% FPL (NACHC, 2015). CHC patients are more ethnically and racially diverse than the national population (Shi, et al., 2013) with a patient population that is 24% Black and 43% Hispanic/Latino (Shi, et al., 2013). CHC patients also may be in worse health compared to other low-income patients. Health center patients are twice as likely as other low-income groups to report fair or poor health and diabetes is 50% more common among CHC patients (Shin, et al., 2013). CHCs thus represent a source of health care for a segment of the population who otherwise encounters barriers to care and has a disproportionate share of health conditions (Nelson, 2002; Adler, et al., 2002).
Although CHC patients have elevated health burdens, racial/ethnic health disparities may be smaller within CHCs relative to the national population. One study found poorer glycemic and blood pressure control for Black relative to White patients and poorer glycemic control for Hispanic relative to White patients in the CHC population, but such disparities were smaller compared to published national estimates (Lebrun, et al., 2013). Another survey of 7 health centers found no ethnic differences in glycemic control among previously diagnosed diabetic CHC patients (Maizlish, et al., 2004). While these findings on attenuated health disparities in CHCs are encouraging, prior research on health disparities in CHCs predates the recent expansion of the CHC program and increase in patients served.
Alongside efforts to expand the program, the Bureau of Primary Health care (BPHC) has implemented multiple initiatives to improve the quality of care. As part of the Affordable Care Act, BPHC was authorized to support the adoption of the Patient-Centered Medical Home (PCMH) model of care in health centers (Shi et al., 2017). PCMH is a nationally recognized model of care emphasizing better quality and experience of care for patients. PCMH seeks to improve the quality of care by ensuring a team-based approach to care that is patient-centered, comprehensive, and coordinated across various elements of the healthcare system (Peikes, et al., 2011). PCMH also emphasizes the use of electronic health records and health information technology to promote patient engagement strategies and quality improvement activities (Peikes, et al., 2011). PCMH-recognized health centers report better performance on clinical measures than health centers that are not PCMH-recognized (Shi et al., 2017; Hu et al., 2018; Landon et al., 2007). As of today, 1,058 or 77% of all health centers have received PCMH recognition (HRSA, 2022), yet the impact of BPHC’s quality improvement initiatives on racial and ethnic disparities is unknown.
This study uses 2019 data from the Uniform Data System (UDS) to describe glycemic and blood pressure control among CHC patients by racial/ethnic group and related racial/ethnic disparities. Rates of blood pressure control and glycemic control have been shown to respond to quality-of-care initiatives, such that health centers may improve levels of controlled conditions in their patient population through effective monitoring, coordinated care, and medication management (Campbell, et al., 2017; Sidorenkov, et al., 2013). In addition, because the magnitude of health disparities may vary between CHCs due to differences in resources and quality of care provided, we examine associations between CHC characteristics (i.e., number of patients served, CHC designation years, and PCMH recognition status) and racial/ethnic disparities in glycemic and blood pressure control. Not only has PCMH recognition status been shown to impact clinical outcomes (Shi et al., 2017; Hu, et al., 2018), research has shown that both length of time in the health center program and size of the organization are related to clinical performance (Lebrun, et al 2013).
By quantifying the magnitude of racial/ethnic disparities in control of cardiometabolic conditions, these findings may indicate whether CHCs attenuate health disparities. Moreover, identifying associations between CHC characteristics and control of cardiometabolic conditions by racial/ethnic group could support further BPHC quality improvement initiatives aimed at eliminating health disparities.
Results show rates of blood pressure control are 10.5 percentage points (pp) lower for Black patients with a hypertension diagnosis relative to White patients. This is equivalent to an excess of 119,942 Black hypertensive patients with uncontrolled blood pressure if rates were comparable to White patients. Rates of glycemic control are 4.6 and 5.0 pp lower for Black and Hispanic patients with diabetes relative to Whites. These differences suggest that an excess of 23,172 Black and 45,597 Hispanic diabetic patients have uncontrolled HbA1c than would be the case if rates were comparable to non-Hispanic Whites.
Results from regression model testing indicate a consistent finding of improved control of glycemia and blood pressure across racial/ethnic groups with PCMH certification. In particular, glycemic control is 1.08 to 2.27 pp higher for PCMH-certified relative to non-PCMH-certified CHCs, although the estimate for Black patients is not statistically significant. Blood pressure control is 2.54 to 3.99 pp higher for each racial group with PCMH certification. Results for other CHC characteristics did not show consistent patterns across racial groups or outcomes.