(P280) ROLE OF GENDER-RELATED FACTORS IN THE ASSOCIATION BETWEEN HYPERTENSION AND WHITE MATTER HYPERINTENSITIES ACROSS SEXES

Background: Hypertension (HTN) is a major global health challenge that affects several vascular beds, including the brain, but there is limited evidence regarding sex differences in this association. Moreover, a notable gap exists in understanding how gender-related factors, defined as a social construct encompassing roles, identity, relations, and institutionalized gender, may contribute to these differences. This study aims to investigate sex differences in the association between HTN and brain structure and explore the contribution of gender.

METHODS AND RESULTS: This cohort study used magnetic resonance imaging (MRI) data from 41,300 UK Biobank participants. HTN status was determined through hospital records and self-report, and brain structure with white matter hyperintensities (WMHs) volumes, measured using MRI. Eight gender-related factors, including unpaid work, caregiving, unemployment, risk-taking behavior, living alone, education, income and material deprivation, were examined. Generalized linear models were used to evaluate the interactions between sex and HTN in the entire sample, and between each gender-related factor and HTN in males and females. Effect modification was also evaluated using the Z-test to compare the beta coefficients of the HTN-WMHs association across strata.

The sample comprised 19,260 males and 22,040 females aged 40-69 years at baseline, with 27.3% hypertensive. Hypertensive males (7.7±9.2 mL) and females (7.2±8.8 mL) had greater WMHs compared to their normotensive counterparts (males: 4.7±5.9 mL, females: 3.9±5.2 mL). HTN was associated with increased WMHs in both sexes, more so in females (interaction sex*HTN, p = 0.007). The main effects model showed that low income was significantly associated with greater WMHs in females, but no gender-related factor was associated with WMHs in males after controlling for clinical, behavioral, and other gender-related factors. No significant interactions between HTN and gender-related factors were found in both males and females. In the stratified analysis by gender-related factors, females with lower material deprivation demonstrated a significantly greater increase in WMHs compared to those with greater material deprivation. No other gender-related factor in females or males interacted with HTN to magnify the association with WMHs.

Conclusion: Socio-economic factors, particularly in females, showed an association with WMH volume, with lower material deprivation associated with greater increases. These findings underscore the importance of considering both biological and social determinants to effectively address hypertension risks.