This prospective, randomized study investigates the effect of two immunosuppressive treatment regimens on quality of life after renal transplantation. At 3 months after transplantation, patients treated with cyclosporine (CsA) and prednisone (Pred) were allo cated to either withdrawal of Pred (n=60) or to con version of CsA to azathioprine (Aza) (Aza-Pred, n=60). Quality of life was evaluated just before randomiza tion, and at 6 and 12 months after transplantation using the Sickness Impact Profile (SIP), the Affect Bal ance Scale (ABS), the Center for Epidemiological Stud ies Depression Scale (CES-D), measures of satisfaction with several domains o f life experience, and a popula tion-specific physical symptoms questionnaire. In both groups, the overall SIP score as well as the scores on its physical and psychosocial dimensions improved continuously after transplantation, reaching levels that are comparable to those found in the general population. The occurrence of acute or chronic rejec tion had a significantly negative effect on SIP and CES-D scores. Intention-to-treat analysis showed no differences between groups for scores on SIP, ABS, CES-D, and satisfaction measures. Exclusion of 41 pa tients who did n ot strictly adhere to their originally designated therapy showed a tendency for better psy chosocial SIP scores in CsA patients (P=0.05), which mainly resulted from a difference on the category of social interaction (P-0,01). This difference occurred despite a similar rejection rate and worse renal func tion in CsA-treated patients. Shortly after steroid withdrawal, a high proportion of CsA patients com plained of stiff or painful muscles (CsA: 74%, Aza-Pred: 36%; P = 0.002). Our data indicate that if successfully completed, CsA monotherapy from 3 months after transplantation may lead to a higher degree of psycho social well-being as compared with conversion from CsA-Pred to Aza-Pred. It seems likely that this advan tage is related to the withdrawal of Pred.One of the primary goals of renal transplantation is to improve the quality of life of the patient with end-stage renal disease. Traditional research efforts, however, have mainly been directed at prolonging patient and graft survival. These survival rates have improved considerably during the last decades and any further progress will be hard to achieve. Therefore, it is not surprising that the quality of life of the patients with prolonged survival is receiving a growing amount of attention (i, 2).The type of immunosuppressive drug therapy is one of the factors that determine the quality of life after renal trans plantation. First, an effective immunosuppressive regimen, leading to prolonged patient and graft survival, is a prereq uisite to reach an optimal level of quality of life. Besides, treatment schedules may act more directly on quality of life by means of their adverse effects, which will differ according to the drugs that are used. Patients' psychosocial function ing, which they will partly attribute to prescribed medica tion, will in turn hav...