Reduced activity restriction buffers the relations between chronic stress and sympathetic nervous system activation.

OBJECTIVES: Caregivers of dementia patients are at risk for developing cardiovascular disease (CVD), and this risk increases the longer they provide care. Greater perceptions that caregiving restricts social/recreational activities (i.e., activity restriction [AR]) has been associated with poorer health, and AR may exacerbate the relations between stress and health outcomes. The current study examined the interactive role of greater exposure to stress and increased AR on plasma catecholamine (CAT) levels: norepinephrine (NE) and epinephrine (EPI).
METHOD: A total of 84 dementia caregivers completed a standard assessment battery, and a nurse collected blood, which was assayed for NE and EPI. Separate regressions for NE and EPI were used to determine whether the relations between years caregiving and CATs were greater in those with high versus low AR.
RESULTS: A significant interaction was found between years caregiving and AR in predicting resting EPI (p = .032) but not resting NE (p = .103). Post hoc analyses indicated that years caregiving was significantly associated with EPI when AR was high (p = .008) but not when AR was low (p = .799). Additionally, years caregiving was not significantly associated with NE when AR was high or low. DISCUSSION: The subjective experience of AR can play an important role in determining risk for detrimental physical health outcomes, particularly CVD risk.