Does a Short Gratitude Intervention Impact Cardiovascular Reactivity to Stress?

This study investigates the effects of a gratitude intervention on cardiovascular responses to stress. Cardiovascular reactions to stress are a substantial risk factor for cardiovascular illness, a leading cause of global mortality, and thus investigating factors that can mitigate the adverse effects of stress is important for reducing longer-term risk of cardiovascular diseases. A convenience sample of 129 participants underwent a laboratory-based stress task while their systolic blood pressure, diastolic blood pressure, and heart rate were measured. Participants were randomly assigned to either a gratitude letter intervention or an active control condition. Results of mixed between-within ANOVAs revealed no significant time by intervention interaction for diastolic blood pressure (F(1, 109) = 1.21, p =.27), or heart rate (F(1, 109) = 1.86, p =.18). However, there was a significant time by intervention interaction for systolic blood pressure (F(1, 120) = 4.67, p =.03), demonstrating that the pattern of increase for systolic blood pressure differed by experimental condition. These findings provide support for the hypothesis that gratitude may have a beneficial relationship with cardiovascular reactions to stress. Future research should replicate and extend these findings with larger and more diverse samples and a longer intervention period, assess additional cardiovascular parameters, and explore long-term relationships between gratitude, cardiovascular reactivity, and health outcomes.