Racial and Ethnic Disparities in Diagnosis of Chronic Medical Conditions in the USA.

BACKGROUND: There exist racial and ethnic disparities in the prevalence of chronic medical illnesses. However, it is unclear if the disparities arise from patients' self-reported estimates on these diseases and whether there is an association between healthcare utilization and diagnosis.

OBJECTIVE: To estimate national racial/ethnic prevalence of undiagnosed hypertension, diabetes, high cholesterol, and kidney disease and identify characteristics associated with undiagnosed diseases.

DESIGN: Retrospective analysis of multi-year survey data.

PARTICIPANTS: Adults 18 years and older who participated in the National Health and Nutrition Examination Survey during 2011-2014 (n = 10,403).

MAIN OUTCOMES: Undiagnosed hypertension (SBP ≥ 140 or DBP ≥ 90 on physical examination with no history of hypertension), undiagnosed diabetes (hgba1c ≥ 6.5% with no history of diabetes), undiagnosed high cholesterol (LDL ≥ 160 mg/dL with no history of high cholesterol), and undiagnosed kidney disease (eGFR ≤ 30 with no history of kidney disease).

RESULTS: The study sample was categorized into Whites, Blacks, Hispanics, Asians, and Other. After adjusting for sociodemographic characteristics, Asians had increased odds of undiagnosed hypertension (OR = 1.41 [1.06-1.86]) and diabetes (OR = 6.16 [3.76-10.08]) compared to Whites. Blacks (OR = 2.53 [1.71-3.73]) and Hispanics (OR = 1.88 [1.19-2.99]) had increased odds of undiagnosed diabetes compared to Whites. Multivariate logistic regression analysis indicated that not having any health insurance was associated with increased odds of undiagnosed diabetes and hyperlipidemia (OR = 1.56 [1.00-2.44] and OR = 2.08 [1.44-3.00], respectively). A recent healthcare visit was associated with a lower likelihood of having undiagnosed hypertension (OR = 0.58 [0.41-0.83]) and diabetes (OR = 0.35 [0.18-0.69]).

CONCLUSIONS: In a nationally representative cohort, Asians had higher rates of undiagnosed hypertension and diabetes, and all minorities were more likely to have undiagnosed diabetes compared to Whites. Healthcare utilization was associated with undiagnosed medical conditions. Our study showed that reliance on self-reported data may systemically underestimate the prevalence of chronic illnesses among minorities and further research is needed to understand the significance of healthcare utilization in health outcomes.