Risk of Recurrent ICH Is Higher Among Blacks and Hispanics
The increased severity of hypertension among minorities does not fully account for their increased risk.
Neurology Reviews. 2018 July;26(7):50
Compared with their white peers, black and Hispanic patients with intracerebral hemorrhage (ICH) have a higher risk of recurrence, according to data published online ahead of print June 6 in Neurology. Although black and Hispanic patients have more severe hypertension than whites do, severity of hypertension does not fully account for this increased risk. Future studies should examine whether novel biologic, socioeconomic, or cultural factors play a role, said the researchers.
The scientific literature indicates that blacks and Hispanics have a higher risk of first ICH than whites do. Alessandro Biffi, MD, head of the Aging and Brain Health Research group at Massachusetts General Hospital in Boston, and colleagues hypothesized that hypertension among these populations might contribute toward this increased risk. Because the subject had not been explored previously, Dr. Biffi and colleagues investigated the role of blood pressure and its variability in determining the risk of recurrent ICH among nonwhites.
Alessandro Biffi, MD
An Analysis of Two Studies
The authors examined data from a longitudinal study of ICH conducted by Massachusetts General Hospital and from the Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study. They included patients who were 18 or older with a diagnosis of acute primary ICH in their analysis.
At enrollment, participants reported their race or ethnicity during a structured interview and underwent blood pressure measurement. The investigators performed follow-up through phone calls and reviews of medical records. Every six months, investigators recorded at least one blood-pressure measurement and quantified blood-pressure variability. Dr. Biffi and colleagues used Cox regression survival analysis to identify risk factors for ICH recurrence.
Systolic Blood Pressure Was Associated With Recurrence
Of the 2,291 patients included in the analysis, 1,121 were white, 529 were black, 605 were Hispanic, and 36 were of other race or ethnicity. The median systolic blood pressure during follow-up was 149 mm Hg for black participants, 146 mm Hg for Hispanic participants, and 141 mm Hg for white participants. Systolic blood pressure variability also was higher for black participants (median, 3.5%), compared with white participants (median, 2.8%).
In all, 26 (1.7%) white participants had ICH recurrence, compared with 35 (6.6%) black participants and 37 (6.1%) Hispanic participants. In univariable analyses, higher systolic blood pressure and greater systolic blood pressure variability were associated with increased ICH recurrence risk. Diastolic blood pressure and diastolic blood pressure variability, however, were not associated with ICH recurrence risk.
In multivariable analyses, black and Hispanic race or ethnicity remained independently associated with increased ICH recurrence risk in both studies, even after adjustment for systolic blood pressure and systolic blood pressure variability. Exposure to antihypertensive agents during follow-up was not associated with ICH recurrence and did not affect the results significantly. The associations were consistent in both studies.
Rodriguez-Torres A, Murphy M, Kourkoulis C, et al. Hypertension and intracerebral hemorrhage recurrence among white, black, and Hispanic individuals. Neurology. 2018 Jun 6 [Epub ahead of print].