Predicting intentions and adherence behavior in the context of organ transplantation: Gender differences of provided social support

Objectives: Medication non-adherence is a common problem in organ transplantation patients with severe consequences for the patients' health. This study aimed at examining the determinants of intention formation and adherence behavior based on the Theory of Planned Behavior (TPB). Moreover, to account for the role of patients' partners, provided social support by partners was included. Here, support provided by female partners was hypothesized to be more effective than support provided by male partners. Method: This cross-sectional study comprised 121 heart, liver, lung, and kidney transplant recipients (n = 81 men; mean age = 54.32, SD = 13.32) and their partners (mean age = 51.99, SD = 13.67). Patients completed a questionnaire with TPB variables and a validated measure of self-reported adherence. Partners reported their provided social support with regard to medication adherence of the patients. Results: For the prediction of intention to adhere to medication, the non-significant main effect of provided social support was qualified by partners' gender: Support provided by women was positively related to patients' intention to adhere, whereas support provided by men was slightly negatively related to the intention to adhere in their female spouses. Intentions in turn emerged together with relationship quality as the most important predictor of adherence behavior. Conclusion: The beneficial effects of support provided by women could be replicated within the framework of the TPB in the context of organ transplantation. Interventions should focus on increasing the effectiveness of support provision of male partners and on promoting relationship quality. (C) 2011 Elsevier Inc. All rights reserved.