Hostility, sodium consumption, and cardiovascular response to interpersonal stress

Previous studies have reported poorer health behaviors in high vs. low hostile subjects. The role of stress in these observed differences has not been explored although interpersonal stress does increase cardiovascular response in high hostiles. Given evidence that stress may induce increased salt-intake, this study examined the role of hostility and interpersonal stress in increasing sodium consumption in addition to cardiovascular reactivity.

Sixty-nine male undergraduates were categorized into high (HiHo) and low hostile (LoHo) groups based on Buss-Durkee Hostility Inventory scores. Subjects engaged in either a math task with harassment, math task without harassment, or a control/rest condition. Sodium intake was assessed posttask by having subjects ingest a sodium-free soup that was presented with a saltshaker without any comments. Cardiovascular measures were also recorded.

HiHo subjects consumed more salt than LoHo subjects irrespective of experimental condition. HiHo subjects who were harassed also exhibited greater cardiac output, systolic blood pressure, and forearm blood flow than did HiHo nonharassed, HiHo control, or LoHo subjects.

HiHo subjects exhibited increased salt-intake, although evidence for stress-induced salt-intake was not obtained. Nonetheless, the combination of salt and stress may contribute to the cardiovascular hyperreactivity and risk for cardiovascular disease in hostile individuals.