Poster #21 - Social buffering and friendship: the presence of a friend attenuates blood pressure and heart rate among Brazilian emerging adults

• In Event: 2-110 - Poster Session 07
  In Poster Session: PS 07 Section - Biological Processes: Psychophysiology

Integrative Statement

Social buffering is the process through which the presence of sources of support can improve the physiological response to a psychological challenge. Limited research has examined this association among emerging adults, especially in majority world settings. The present study examined the effectiveness of friends support on heart rate (HR) and blood pressure (BP) in a sample of Brazilian emerging adults. Sixty participants were randomly assigned to two different conditions: alone (n=30) and accompanied by a friend (n=30). More than half of participants were males (57%), aged from 18 to 30 years (mean age=21.1, sd=2.6) with 62% self-reported as white, 29% as mixed ethnicity (Pardo), and 9% as black (Preto). Participants completed the Trier Social Stress Test and provided BP and HR at 4 time points during the experimental session, and also completed a self-report survey, not used in this analysis. We experimentally manipulated the provision of friend support during an adapted Trier Social Stress Test (TSST) and examined how friend’s availability influenced HR and BP during the experimental session. A two-level multilevel modeling was performed using the dependent variables (systolic, diastolic blood pressure and heart rate separately) measured over time nested within individuals (see table 1). At the between-individual level, we tested for differences in the intercept, the rise from baseline and the return to baseline as a function of ethnicity (dummy code where 1 represented students non-white students), gender (standardized) and age (also standardized). These variables were entered first as covariates. As the last step of the model building process we tested for differences in the three random effects based on whether the subjects had a friend present or not. When examining whether the presence of a friend moderated the rise from baseline and the return to baseline for diastolic blood pressure (DBP), the return to baseline following the stressor was significantly stronger among the students with their friend present (b = -.76, S.E. = .38, t(55) = 2.00, p < .05), which improved the estimation of the return to baseline DBP (PRPE = 8.72%; ∆χ2(1) = 6.13, p < .05). For systolic blood pressure, there were no effects of having a friend present on either the rise from baseline or the return to baseline. Finally, we examined whether the presence of a friend moderated the rise from baseline and the return to baseline for heart rate (HR, Figure 1). One weak effect emerged. The return to baseline HR following the stressor was marginally stronger among the students with their friend present (b = -.41, S.E. = .25, t(55; 1-tailed) = 1.64, p < .05). The addition of the presence of a friend improved the estimation of the return to baseline (PRPE = 3.38%; ∆χ2(1) = 10.97, p < .05). The discussion of the results acknowledges the limitations of this study, identifies promising areas for additional research.

Authors

• Josafa Da Cunha, Universidade Federal do Paraná
  Presenting Author

• Jonathan Santo, University of Nebraska Omaha
  Non-Presenting Author

• Sarah Roza, Federal University of Parana
  Non-Presenting Author

• Thiago Roza, Federal University of Parana
  Non-Presenting Author

• Beatriz Bermudez, Federal University of Parana
  Non-Presenting Author