Resting Heart Rate Variability, Perceived Emotion Regulation, and Low-Risk Drug Use in College-Aged Adults: Gender as a Moderator

FIGURE 1. Conceptual moderation, mediation, and moderated-mediation models. (A) PROCESS Model 1 (48): moderation models of variables of interest (HRV, heart rate variability; ER, emotion regulation; DAST, Drug Abuse Screening Test). Models 1A and 1B refers to hypothesized models, and Models 1C and 1D are alternative models that were examined (see section “Materials and Methods” for details). (B) PROCESS Model 4 (48): mediation models of variables of interest (HRV, heart rate variability; ER, emotion regulation; DAST, Drug Abuse Screening Test). Model 2A refers to the hypothesized model, and Models 2B and 2C are alternative models that were examined (see section “Materials and Methods” for details). (C) PROCESS Model 58 (48): moderated-mediation models of variables of interest (HRV, heart rate variability; ER, emotion regulation; DAST, Drug Abuse Screening Test). Model 3A refers to the hypothesized model, and Models 3B and 3C are alternative models that were examined (see section “Materials and Methods” for details).

FIGURE 2. Scatterplots on the association between resting HRV and ER difficulties on groups of interest. Scatterplots illustrating the associations between resting heart rate variability (HRV) and Difficulties in Emotion Regulation Scale (DERS) scores on four major groups of interest. These groups were obtained through the stratification of our full sample by gender and drug group. Panel (A), which represents women with no history of drug use, shows the only significant association between HRV and DERS. Panel (B) (women with a history of drug use), panel (C) (men with no history of drug use), and panel (D) (men with a history of drug use) all show non-significant associations between HRV and DERS (see section “Materials and Methods” for details). *p < 0.05.

FIGURE 3. Conditional effects of moderation test. This figure depicts the association between drug use and emotion regulation (ER) difficulties moderated by gender (see section “Materials and Methods” for details).

FIGURE 4. Mediation and moderated-mediation model. Panel (A) depicts a mediation model illustrating emotion regulation (ER) difficulties mediating an indirect association between resting HRV and drug use. Statistics reported include unstandardized betas (B), standard error (in brackets) and the bootstrapping CI’s (lower limit, upper limit) for each path of the model. Path A represents the association between the independent variable (resting HRV) and ER difficulties. Path B represents the association between ER difficulties and drug use. Furthermore, there were also direct and indirect paths between resting HRV and drug use. The direct path represents the direct effect between resting HRV and drug use. The indirect path represents the indirect effect of resting HRV on drug use through ER difficulties. Significant effects bolded. *p < 0.05 (see section “Materials and Methods” for details). Panel (B) depicts a moderated-mediation model illustrating the effects of utilizing gender as a moderator on the mediation analysis seen in (A). Statistics reported include unstandardized betas (B), standard error (in brackets) and the bootstrapping CI’s (lower limit, upper limit) for each path of the…