Social support and dietary changes in a couples-based treatment for coronary heart disease

The current study examined a mediational model of social support as the mechanism of change in a couple-based treatment for dietary behavior among patients with coronary heart disease. None of the assumptions of mediation regarding social support were met. Treatment condition (individual versus couple) did not predict changes in social support or changes in diet. Changes in social support did not predict changes in diet, possibly due to the lack of significant change in social support from pre to post treatment. Considering social support as a stable characteristic of partners, post hoc analyses examined social support as a moderator of treatment's effects on diet. Results demonstrated that patients in the individual treatment condition whose partners provided higher amounts of expressive support showed lower increases in percent of calories from fat. In addition, patients in the individual treatment condition whose partners provided higher positive affect during social support showed greater increases in percent of calories from fat and saturated fat. In addition to examining the role of social support in a couple-based treatment for health behavior change, the current study revised and applied a coding system for social support in couples to discussions about one partner's health. Exploring relationships among different aspects of social support and relationship adjustment demonstrates the ways in which instrumental and expressive support behaviors are linked with the quality and emotion with which partners performed those behaviors.