# Unraveling Racial Disparities in Portal Hypertension: A Clinical, Spectroscopic andSNP Approach

> **NIH NIH R21** · BAYLOR COLLEGE OF MEDICINE · 2022 · $243,822

## Abstract

Portal hypertension is the major consequence of cirrhosis which can lead to catastrophic complications such as
massive, potentially exsanguinating hemorrhage from esophageal and gastric varices. Epidemiological studies
indicate that African Americans (AAs) have higher mortality from portal hypertensive complications than Whites
but the mechanism of disparity i.e. whether it is biologic or socio-economic remains unclear. Portal hypertension
is characterized by increase in gut mucosal blood flow (gastropathy, colopathy) that in some studies has been
shown to correlate with portal pressure and thus, severity of liver disease. We have developed a powerful
spectroscopic technique- polarization gating spectroscopy (PGS) which can accurately measure gut mucosal
blood flow. We have used PGS extensively to detect colorectal neoplasia by detecting increased blood flow in
normal appearing colonic tissue but have not applied to issues in portal hypertension. Our colorectal data
demonstrated distinct microvascular patterns in AAs and Whites. We have preliminary data with the more
powerful next generation polarization gated spectroscopy (NG-PGS) that shows marked augmentation of
duodenal microcirculation in cirrhosis. In addition, the biological basis of racial disparity is supported by racial
differences in other circulatory disorders like systemic hypertension and in single nucleotide polymorphisms
involved in genes involved in portal hypertension. The goal of this R21 is to elucidate the biological differences
between AAs and Whites that lead to disparities in portal hypertension by utilizing a novel, less-intrusive
spectroscopic microvascular duodenal mucosal biomarker that can be a potential surrogate for portal pressure.
We will leverage the extraordinary resources at Boston University Medical Center, a safety net hospital serving
a diverse population (40% AAs) with high number of liver visits. We will perform a prospective case control study,
in with cirrhotics and stratify them by well-established clinical markers of clinically significant portal hypertension
(CSPH) i.e. presence and size of varices and correlate it with race. We will examine if depth-selective NG-PGS
assessment of duodenal microcirculation (total hemoglobin, oxygenation status and blood vessel radius) during
standard of care diagnostic upper endoscopy for variceal detection will correlate with presence/size of varices
and have distinct racial signatures in AAs and Whites (aim 1). We will then test the utility of the optimized
duodenal microvasculature biomarker developed in aim 1, as a companion biomarker to detect changes in portal
pressure by changes in duodenal microcirculation with a well-established therapeutic agent, octreotide test (aim
2). Using these novel and rigorous approaches, ours will the first study to provide into mechanisms of disparities
in portal hypertension. Clinically, these studies will open new vistas in the management of portal hypertension.
Future R01 applic...

## Key facts

- **NIH application ID:** 10101668
- **Project number:** 5R21MD013631-03
- **Recipient organization:** BAYLOR COLLEGE OF MEDICINE
- **Principal Investigator:** Vadim Backman
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $243,822
- **Award type:** 5
- **Project period:** 2020-02-06 → 2022-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10101668

## Citation

> US National Institutes of Health, RePORTER application 10101668, Unraveling Racial Disparities in Portal Hypertension: A Clinical, Spectroscopic andSNP Approach (5R21MD013631-03). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10101668. Licensed CC0.

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