Biological impact of sexual minority stress: The role of emotion suppression in the cardiovascular conundrum

A paradoxical pattern of elevated sympathetic vasoconstriction (increased total peripheral resistance, TPR) alongside enhanced vagally mediated heart rate variability (HRV) —referred to as the Cardiovascular Conundrum— has been consistently observed in Black individuals. While some researchers attribute this profile to genetic factors, others propose that repeated exposure to racial discrimination and the need to suppress associated negative emotions may play a central role. To investigate the underlying mechanisms, we examined 26 heterosexual and 24 lesbian, gay, and bisexual (LGB) individuals, matched by age and sex, at rest and during the recall of a discrimination-related stressful event. Participants were then randomly assigned to either an emotion suppression condition, in which they were instructed to actively suppress negative emotions during a 10-minute recovery period, or a control condition with no such instruction. Consistent with our hypothesis, both heterosexual and LGB participants in the suppression condition exhibited increased HRV (F = 1.8; η2 = .04) as well as increased TPR (F = 3.9; η2 = .07) during recovery from the discrimination-related task. Notably, only LGB individuals demonstrated the same pattern also in the control condition, suggesting a tendency to spontaneously suppress negative emotions in response to discrimination, with measurable physiological consequences. The replication of the Cardiovascular Conundrum in a different minoritized group supports the hypothesis that minority stress may become biologically embedded. These findings carry significant implications for public health policies and interventions aimed at mitigating the psychophysiological impact of discrimination.