COVID-19 Outcomes Stratified by Control Status of Hypertension and Diabetes: Preliminary Findings From PCORnet, U.S.

HIGHLIGHTS • Among 656,049 adults with COVID-19, 41% had hypertension, and 13% had diabetes.• Approximately one quarter of those with hypertension had blood pressure >140/90.• Approximately one fifth of those with diabetes had HbA1c >9%.• Worse COVID-19 outcomes were more prevalent among those with higher blood pressure.• Hospitalization was more prevalent among those with higher HbA1c.


INTRODUCTION
−8 Furthermore, existing racial and ethnic disparities in the prevalence and control of chronic diseases 5 might exacerbate disparities in COVID-19 outcomes. 9The purpose of this study was to describe the demographic and clinical characteristics and COVID-19 outcomes across strata of disease control for adults with hypertension and diabetes.
Hypertension and diabetes were identified using PCORnet electronic health record documentation from the previous 3 years.Hypertension was defined on the basis of (1) prescription for an outpatient antihypertensive medication (not including centrally acting agents, loop diuretics, or beta-blockers because these are commonly used for other conditions); (2) outpatient centrally acting agents, loop diuretics, or b blockers and either an ICD-10-CM diagnostic code for hypertension or outpatient blood pressure (BP) ≥130/80 mmHg; (3) 2 outpatient BP readings ≥130/80 mmHg on separate days; or (4) 2 ICD-10-CM codes for hypertension on separate days in any care setting.Diabetes was defined as (1) a prescription for an outpatient diabetes medication, (2) HbA1c ≥6.5%, (3) 1 ICD-10-CM code for type 1 diabetes or type 2 diabetes plus metformin, or (4) 2 ICD-10-CM codes for diabetes in any care setting.
Disease control status was identified by the measurement (HbA1c or outpatient BP) most recently available before the COVID-19-positive laboratory test.BP values within 2 weeks before the COVID-19 event were excluded to avoid BP values during the acute illness phase.Up to an 18-month lookback period was used to assess disease control to allow most patients to have had an outpatient visit; patients without an HbA1c or BP value or only with values beyond 18 months before the COVID-19 positive laboratory test were not classified into disease control status categories for diabetes or hypertension, respectively.Hypertension control was categorized into 4 strata (BP <130/80 mmHg, 130-139/80-89 mmHg, 140-159/90-99 mmHg, or ≥160/100 mmHg) using the higher systolic or diastolic value if a patient's values fell into multiple levels.Diabetes control was categorized into 3 strata (HbA1c <7%, 7 to <9%, ≥9%).Collected patient demographic and clinical characteristics included age, sex, race (White, Black, Asian, other), Hispanic ethnicity, overweight or obese BMI (≥25 kg/m 2 ), COVID-19 treatments (dexamethasone, other corticosteroids, remdesivir), and outcomes (hospitalization, receipt of critical care, receipt of mechanical ventilation, and 60day mortality).All analyses were descriptive in nature; analyses were conducted in 2021 using patient-level data at individual PCORnet sites and then aggregated into this report.Patient-level statistical tests could not be conducted because only summary data were aggregated from individual sites; methods are being developed to conduct pooled regression analyses in the distributed PCORnet environment.This secondary data analysis of aggregate data in support of the federal COVID-19 emergency response was considered not to be human subjects research and was exempt from IRB review.

DISCUSSION
In this study of over 650,000 adults, among those with hypertension or with diabetes, severe COVID-19 outcomes were more common among those with the highest BP and HbA1c levels.Similar findings have been described in other countries; yet, this is the largest study from the U.S. 6−8 Potential effects of poor hypertension and diabetes control on COVID-19 outcomes could disproportionately affect racial and ethnic minorities, given the longstanding disparities in chronic disease management, known health system inequities, and differential COVID-19 risk among these populations. 5,9,12Interestingly, the prevalence of severe COVID-19 was lower among those with BP of 130−139/80−89 mmHg than among those with BP <130/80 mmHg.Those with the lowest BP tend to be older, with more comorbidities and longer history of hypertension 13 ; consistent with this pattern, persons in our analyses with BP <130/80 mmHg were older than those with BP of 130−139/80 −89 mmHg.

Limitations
A key limitation is that we could not adjust for potential confounders, so we could not explore whether differences in patient characteristics or vaccination status may partially explain the observed differences in COVID-19 outcomes by disease control status.Most of our data were collected before widespread vaccine availability, and unfortunately, most early vaccinations occurred in public health drives and were poorly captured in medical records and thus could not be assessed in this study.Other limitations include that (1) not all patients could be classified by chronic disease control status, (2) chronic disease control status may have been misclassified owing to the 18-month lookback period, and (3) approximately 10% of patients were missing data for race and 9% for ethnicity.

CONCLUSIONS
Appropriate and equitable management of hypertension and diabetes is important, 6−8 and the findings of this study can provide information to healthcare providers and to patients living with these chronic diseases.The COVID-19 pandemic may have disrupted healthcare visits, exacerbated existing health disparities, and adversely affected disease management. 14Public health messaging for patients and providers can encourage routine care, use of telehealth, and strategies such as selfmeasured BP monitoring and home blood glucose measurements with clinical support. 15,16Future work can examine whether chronic disease control status is associated with COVID-19 outcomes.

Figure 1 .
Figure 1.COVID-19 outcomes by (A) hypertension control status and (B) diabetes control status.This figure shows variation in inpatient hospitalization, mechanical ventilation, critical care use, and 60D mortality by strata of chronic disease control.For no hypertension, n=389,101, and for no diabetes, n=571,323.For the entire cohort, N=656,049, and outcome prevalences were 14% inpatient hospitalization, 2% mechanical ventilation, 2% critical care, and 3% 60D mortality.

Table 1 .
Demographic and Clinical Characteristics of Patients With COVID-19 by Hypertension Control Status

Table 2 .
Demographic and Clinical Characteristics of Patients With COVID-19 by Diabetes Control Status