Childhood Family Stress and Women's Health: Parasympathetic Activity as a Risk and Resiliency Factor

Abstract

Childhood family stress (CFS) exacerbates risk for physical health problems across the lifespan. Health risks associated with CFS are particularly relevant for women who tend to endorse more CFS than men. Importantly, some evidence suggests that individuals may vary in their susceptibility to CFS. Parasympathetic activity, which helps to regulate automatic bodily activity (e.g., breathing, digestion), has been proposed to represent a marker of plasticity to environmental exposure. However, no research to date has tested whether parasympathetic activity may modulate the impact of early adversity on health. We examined whether parasympathetic activity would moderate the link between CFS and health complaints in a sample of 68 undergraduate women (Mean age = 19.44). Participants self-reported CFS and health complaints. Parasympathetic activity was indexed using high-frequency heart rate variability (HF-HRV) and was evaluated by measuring changes in HF-HRV in response to and following a laboratory-based stress induction. Multiple regression analyses indicated that CFS was significantly associated with more health complaints. Further, HF-HRV in response to stress and during recovery relative to baseline significantly moderated relationship between CFS and health complaints. Specifically, more CFS was significantly associated with more health complaints among women who showed mean or greater decreases in HF-HRV in response to stress. Additionally, lower levels of CFS were associated with fewer health complaints among women who showed mean or greater HF-HRV during recovery relative to baseline. Findings highlight the importance of parasympathetic activity in modulating stress-health links.

Keywords: Biological sensitivity to context; Childhood family stress; Diathesis stress; High-frequency heart rate variability; Women’s health.

Figure 1a.. Moderating Effects of HF-HRV Reactivity in response to the Speech task

Notes. Conditional effects of CFS on physical health under conditions of greater, mean, and less HF-HRV withdrawal in response to the speech task. *p < .05, **p < .01. Less HF-HRV withdrawal = 1 standard deviation above the mean of HF-HRV reactivity (M _{HF-HRV Speech reactivity} = 0.32); Greater HF-HRV withdrawal = 1 standard deviation below the mean of HF-HRV reactivity (M _{HF-HRV Speech reactivity} = −1.28). Higher physical health scores = better health (fewer health complaints).

Figure 1b.. Region of Significance Test for HF-HRV in response to Speech Task: CFS as a Moderator

Notes. The X-axis depicts a standardized continuous range of CFS, whereas the Y-axis depicts a range of the adjusted effect of HF-HRV reactivity to speech task. The straight plot line demonstrates values of the adjusted effect of HF-HRV speech reactivity corresponding to CFS. The curved lines represent 95% confidence interval around the adjusted effect of HF-HRV speech reactivity on physical complaints. The effect is only considered significant when the 95% confidence bands do not include the adjusted effect of HF-HRV (Y-axis) = 0. In this test, greater HF-HRV withdrawal in response to speech task appeared to be associated with less physical complaints at low levels of CFS, SD < 1.11, and significantly associated with more physical complaints at high levels of CFS, SD >1.5.

Figure 2a.. Moderating Effects of HF-HRV reactivity in response to the Math task

Notes. Conditional effects of CFS on physical health at greater, mean, and less HF-HRV withdrawal in response to math task. *p < .05, **p < .01. Less HF-HRV withdrawal = 1 standard deviation above the mean of HF-HRV reactivity (M_{HF-HRV Math reactivity} = 0.21); Greater HF-HRV withdrawal = 1 standard deviation below the mean of HF-HRV reactivity (M_{HF-HRV Math reactivity} = −1.51). Higher physical health scores = better health (fewer health complaints).

Figure 2b.. Region of Significance Test for HF-HRV in response to Math task: CFS as a Moderator

Notes. The X-axis depicts a standardized continuous range of CFS, whereas the Y-axis depicts a range of the adjusted effect of HF-HRV reactivity to math task. The straight plot line demonstrates values of the adjusted effect of HF-HRV math reactivity corresponding to CFS. The curved lines represent 95% confidence interval around the adjusted effect of HF-HRV math reactivity on physical complaints. The effect is only considered significant when the 95% confidence bands do not include the adjusted effect of HF-HRV (Y-axis) = 0. In this test, greater HF-HRV withdrawal in response to math task only appeared to be associated with less physical complaints at low levels of CFS, SD < 0.3.

Figure 3a.. Moderating Effects of HF-HRV during the Recovery Period relative to Baseline

Notes. Conditional effects of CFS on physical health at high, average, and low levels of HF-HRV recovery. *p < .05, **p < .01. Lower HF-HRV recovery= 1 standard deviation below the mean of HF-HRV recovery (M_{HF-HRV Recovery} = −0.60); Greater HF-HRV recovery = 1 standard deviation above the mean of HF-HRV recovery (M_{HF-HRV Recovery} = 0.48). Higher physical health scores = better health (fewer health complaints).

Figure 3b.. Region of Significance Test for HF-HRV during recovery relative to baseline: CFS as a Moderator

Notes. The X-axis depicts a standardized continuous range of CFS, whereas the Y-axis depicts a range of the adjusted effect of HF-HRV during recovery relative to baseline. The straight plot line demonstrates values of the adjusted effect of HF-HRV during recovery relative to baseline corresponding to CFS. The curved lines represent 95% confidence interval around the adjusted effect of HF-HRV during recovery relative to baseline on physical complaints. The effect is only considered significant when the 95% confidence bands do not include the adjusted effect of HF-HRV (Y-axis) = 0. In this test, greater HF-HRV during recovery relative to baseline only appeared to be associated with more physical health complaints at low levels of CFS, SD > −0.3.