Evaluating Control of Hypertension - Effect of Social Determinants

Study Overview
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Brief Summary
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This study evaluates the impact of a large-scale, national expansion of Medicaid on hypertension incidence, screening, treatment, and management. Social Determinants of Health will be assessed as moderators, and comparing states that did versus states that did not expand Medicaid will also be evaluated.

Detailed Description
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The Affordable Care Act (ACA) enacted several provisions intended to improve healthcare for vulnerable populations,including expanding Medicaid eligibility to those earning ≤138% of the federal poverty level (FPL). Since the expansion was not required, as of March 2018, 32 states (and District of Columbia) implemented the expansion and 18 did not. Simulated models predicted the ACA would improve health outcomes and reduce disparities for patients with hypertension, yet actual changes are not yet available. In addition, there is new interest in tracking and utilizing Social Determinants of Health (SDH) in the primary care setting but there is currently little information on how this information will impact Hypertension (HTN) care, especially related to changes to health insurance availability. This study will build on current understanding of how health insurance impacts HTN incidence, screening, treatment, and management by comparing states that did versus did not expand Medicaid as part of the ACA and seeks to understand the influence of SDH on these changes. the investigators will address the following specific aims: Aim 1: Compare HTN incidence, prevalence of undiagnosed HTN, and rates of HTN screening, in Medicaid expansion versus non-expansion states before and after the ACA. Aim 2: Compare HTN treatment (e.g., medication use), and management (e.g., HTN control, systolic and diastolic blood pressure change, risk factors related to HTN control) in Medicaid expansion versus non-expansion states before and after the ACA. Aim 3: Assess the extent to which rates of HTN incidence, screening, and treatment effectiveness among patients who gained insurance versus those continuously insured or uninsured, pre-post ACA, are moderated by individual-level SDH (e.g., race, ethnicity), in expansion states. Aim 4: Explore the interaction between community-level SDH (e.g., neighborhood racial segregation and deprivation) and HTN incidence, screening, treatment, and management among patients who gained insurance relative to those who were continuously insured or uninsured, in expansion states. The findings from this project will be extremely relevant to policy and practice, informing further improvements in the US healthcare system to ensure access to healthcare for vulnerable populations.

Official Title
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Evaluating Control of Hypertension - Effect of Social Determinants

Conditions
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Hypertension

Intervention / Treatment
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* Other: Medicaid Expansion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients in intervention and control states aged 19-64 Exclusion Criteria: Patients outside of age range 19-64

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Medicaid Expansion States<br>Patients receiving care in community health centers in states that expanded Medicaid (intervention group) | Other: Medicaid Expansion<br>* There will be no direct intervention, but rather an observation of change based on whether a state expanded Medicaid or not<br>|
| Non Medicaid Expansion States<br>Patients receiving care in community health centers in states that did not expand Medicaid (control group) | Other: Medicaid Expansion<br>* There will be no direct intervention, but rather an observation of change based on whether a state expanded Medicaid or not<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hypertension incidence | Rates of hypertension diagnosis using the following codes in the EHR: ICD-9: 401.00-401.99, 402.00-405.99 or ICD-10: I10-I15. | 24 months prior to Medicaid expansion vs 24 months post | 
| Undiagnosed hypertension | high blood pressure but no diagnosis or medications can be noted in the EHR diagnostic codes that can be used to document why a diagnosis of hypertension was not made including ICD-10 R03.0 (i.e., white coat syndrome without HTN) and ICD-9 796.2 (i.e., elevated BP without HTN). | 24 months prior to Medicaid expansion vs 24 months post | 
| Hypertension screening | rate of blood pressure screening marked in EHR | 24 months prior to Medicaid expansion vs 24 months post | 
| Hypertension treatment | the number of anti-hypertensive medications prescribed in EHR | 24 months prior to Medicaid expansion vs 24 months post | 
| Hypertension management | blood pressure control: last measure within range of normal for age/risk(s); percent Y/N at last visit, value/date of last measure | 24 months prior to Medicaid expansion vs 24 months post | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insurance status and rates of coverage | Health insurance status derived from EHR data and is primarily based on information collected at each visit | 24 months prior to Medicaid expansion vs 24 months post | 
| Service Utilization | Type of internal services utilized including number and ratio of traditional face to face visits vs. nontraditional encounters and communication via phone, personal health record, and email | 24 months prior to Medicaid expansion vs 24 months post | 
| Preventive service receipt | number of all billed encounters overall and yearly, as well as number of cancer screening, smoking screening, lipid screening, diabetes screening, obesity screening | 24 months prior to Medicaid expansion vs 24 months post | 
| Hypertension related complications | incidence of related complications and diseases derived from EHR data | 24 months prior to Medicaid expansion vs 24 months post | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypertension, Social Determinants of Health, Health Insurance, Medicaid, Affordable Care Act