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Published on: July 21, 2023
Ethnicity, perceived discrimination, and vascular reactivity to phenylephrine
KaMala S Thomas1, Richard A Nelesen, Vanessa L Malcarne
1San Diego State University & University of California, San Diego Joint Doctoral Program in Clinical Psychology, San Diego, California, USA.
Objectives:
This study examined relationships among ethnicity, perceived discrimination, and vascular reactivity to phenylephrine (PE).
Methods:
Seventy-six white patients and 46 black patients were studied at an inpatient clinical research center in response to a bolus intravenous injection of 100 microg PE. Self-report questionnaires assessed perceived discrimination.
Results:
After controlling for body surface area, number of cigarettes smoked, and baseline blood pressure, black patients had greater vascular reactivity to PE than white patients (p = .01). There was also a significant relationship between perceived discrimination and diastolic blood pressure responsiveness to PE (p < .05). Path analyses revealed that perceived discrimination mediated the relationship between ethnicity and diastolic pressor responses. Individuals who perceived more discrimination had a larger increase in diastolic blood pressure in response to PE.
Conclusion:
These data suggest perceived discrimination is associated with increased blood pressure responsiveness to PE.
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