LATE ACUTE REJECTION AND SUBCLINICAL NONCOMPLIANCE WITH CYCLOSPORINE THERAPY IN HEART-TRANSPLANT RECIPIENTS

Background: Although noncompliance with immunosuppressive medication i s recognized as a critical behavioral risk factor for late acute rejec tion episodes and graft loss after transplantation, little is known ab out the degree of subclinical cyclosporine noncompliance, its associat ed risk for acute late rejection episodes (>1 year after transplantati on), and its determinants in heart transplant recipients. Methods: The convenience sample of this longitudinal study included 101 European h eart transplant recipients (87 men and 14 women), with a median age of 56 (Q1 = 50, Q3 = 61) and a median posttransplantation status of 3 (r ange 1 to 6) years. Subclinical cyclosporine noncompliance was measure d during a 3-month period with electronic event monitoring. Selected s ociodemographic, behavioral, cognitive, emotional, health, and treatme nt-related determinants of medication noncompliance were measured by u sing instruments with established psychometric properties or by patien t interviews. With the use of iterative partitioning methods of cluste r analysis, including nonstandardized electronic event monitoring comp liance parameters, patients were categorized by degree of subclinical cyclosporine noncompliance into a 3-cluster solution. Results: Overall compliance was high, with a median medication taking compliance of 99 .4%. The 3 derived clusters, that is, excellent compliers (84%), minor subclinical noncompliers (7%), and moderate subclinical noncompliers (9%), differed significantly by degree of subclinical noncompliance (p < .0001) and showed a 1.19%, 14.28%, and 22.22% incidence of late acu te rejections (p = .01), respectively. The 3 groups also differed in t erms of former medication noncompliance (p = .02), appointment noncomp liance (p = .03), and perceived self-efficacy with medication taking ( p = .04). Conclusions: Although in absolute numbers cyclosporine compl iance in this sample was high, minor deviations from dosing schedule w ere associated with an increased risk for acute late rejection episode s. This suggests a pivotal role of patient compliance in successful lo ngterm outcome after transplantation.