Multi-ethnic variation in the ties that bind rumination and heart rate variability: Implications for health disparities.

Higher self-reported rumination, a common form of trait perseverative cognition, is linked with lower resting heart rate variability (HRV), which indicates poorer cardiac function and greater disease risk. A meta-analysis and systematic review indicated that in samples with fewer European Americans, the association of rumination with both heart rate and blood pressure was stronger. Thus, trait rumination may be more strongly associated with resting HRV among ethnically minoritized populations. The current study investigated whether differences in the association of self-reported rumination with resting HRV varied by ethnicity in a sample (N = 513; Mage  = 19.41; 226 Women) of self-identified African Americans (n = 110), Asian Americans (n = 84), and European Americans (n = 319). Participants completed a five-minute baseline period to assess resting HRV, followed by the Ruminative Responses Scale, which contains three facets of rumination including brooding, depressive, and reflective rumination. On average, Asian Americans reported higher levels of rumination relative to European Americans. African Americans had higher resting HRV than Asian Americans. Adjusting for covariates, higher self-reported rumination was significantly associated with lower resting HRV in both African and Asian Americans, but not significantly so in European Americans. This finding was consistent for brooding and reflective, but not depressive rumination. Overall, this study lends insight into a psychological mechanism-rumination-that may impact health disparities among ethnically minoritized individuals, contributing to an understanding of how stress gets under the skin among such minoritized populations.

Attachment insecurity, heart rate variability, and perceived social support in a diverse sample of young adults.

Psychological and physical factors are robustly associated with perceived social support. Drawing from the literature on attachment style in adults and psychophysiology, we examined the possibility that the interaction of attachment insecurity and resting heart rate variability (HRV) was associated with perceived social support in a diverse sample of young adults living in the U.S (N = 145, Mage = 20.45) that was majority Latino (n = 77). Analyses revealed three key findings. First, in the overall sample, attachment avoidance and attachment anxiety were negatively associated with perceived social support, but in the Latino sample, only attachment avoidance was negatively associated with perceived social support. Second, HRV was not associated with perceived social support in the overall sample nor in the Latino sample. Third, attachment insecurity and HRV interacted to predict perceived social support only in the Latino sample such that, for those with lower levels of HRV, attachment anxiety was positively associated with perceived social support. This study underscores the importance of examining both psychological and physiological processes with careful consideration of ethnicity/culture in order to better understand perceived social support.

Resting heart rate variability and emotion regulation difficulties: Comparing Asian Americans and European Americans.

Asian Americans and European Americans differ in emotion regulation (ER), particularly regarding strategies utilized to adaptively engage in ER. Resting heart rate variability (HRV), a biomarker of ER ability, is suggested to differ between Asian Americans and European Americans, but evidence for such differences has been inconsistent. Yet, research has not considered how Asian Americans and European Americans might differ in the well-established link between resting HRV and ER difficulties, which might lend a better understanding of such inconsistencies. In 374 college-aged individuals (66 Asian Americans; 311 European Americans; 190 women; mean age = 19.3 years [Min. 18, Max 38]), we examined if ethnicity moderated the link between resting HRV and self-reported ER difficulties. Resting HRV was obtained during a 5-min resting-baseline period, and ER difficulties were assessed using the Difficulties in ER Scale, which contained six facets of ER difficulties. Adjusting for gender and body mass index, moderation analyses showed a stronger association between resting HRV and ER difficulties in Asian Americans compared to European Americans. When examining facets of ER, ethnicity moderated only the link between resting HRV and difficulties in accessing ER strategies when facing negative emotions. At lower levels of HRV, Asian Americans reported greater difficulties in ER relative to European Americans. This effect diminished and trended in the opposite direction among those with higher HRV. In sum, these results provide novel evidence that higher resting HRV might be particularly important for adaptive ER among Asian Americans - a marginalized ethnic group - in the U.S.

Cultural differences in stress and affection following social support receipt.

Culturally appropriate social support predicts better psychological outcomes. Motivation for providing social support may vary cross-culturally, with more independent cultures valuing self-esteem and more interdependent cultures valuing closeness. Participants in the U.S. (N = 85) and Singapore (N = 78) reported on emotions and social support receipt using the Day Reconstruction Method. We examined cultural differences in stress and affection, and tested country as a moderator of the associations between both social support receipt and social support motivation, and next-episode emotions. Multilevel modeling analyses showed that not only did the emotional correlates of social support receipt vary by country, but that recipient perceptions of esteem-building and closeness-fostering SS also differentially correlated with subsequent emotion. For example, esteem-building SS predicted greater next-episode stress for Singaporean participants, but less stress in the U.S. Esteem-building SS predicted more next-episode affection only in the U.S. Culturally appropriate social support predicts positive psychological outcomes. This research highlights the importance of considering culture when examining the dynamic emotional correlates of social support receipt.

A Close Examination of the Use of Systolic Time Intervals in the Calculation of Impedance Derived Cardiac Autonomic Balance and Regulation.

Traditionally, impedance derived measures of cardiac autonomic balance (CAB) and regulation (CAR) are calculated using indices of heart rate variability (HRV) that primarily reflect parasympathetic nervous system activity (e.g., high-frequency HRV | HF-HRV) and pre-ejection period (PEP; a systolic time interval and measure of sympathetic activity). However, HF-HRV and PEP are considered measures of chronotropic and inotropic cardiac influence, respectively. Left ventricular ejection time (LVET) is a systolic time interval that reflects sympathetic chronotropic influence, and therefore may be a more appropriate measure for calculating CAB and CAR compared to PEP. Thus, the current study evaluates both PEP and LVET in the calculation of CAB and CAR. Data from 158 healthy participants (mean age = 19.09 years old, SD = 1.84 years) were available for analyses. CAB and CAR values were calculated using both HF-HRV and the root mean square of successive differences, in addition to both PEP and LVET, in accordance with previously established guidelines. Analyses showed that correlations were significantly weaker between CAB and CAR calculated using LVET for both HF (z = 5.12, p < 0.001) and RMSSD (z = 5.26, p < 0.001) than with PEP. These data suggest that LVET, compared to PEP, provides better "autonomic space" as evidenced by a lack of correlation between CAB and CAR computed using LVET. We stress that future research consider calculating CAB and CAR using chronotropic measures for both parasympathetic and sympathetic activity, as doing so may yield more accurate and independent measures of cardiac autonomic activity compared to a mixture of inotropic (i.e., PEP) and chronotropic (i.e., HF-HRV) measures.