Evaluation of adherence and clinical outcomes in patients undergoing allogeneic haematopoietic stem cell transplantation.

Objective: To measure adherence to cyclosporine, tacrolimus and  sirolimus prophylaxis against secondary graft failure; cyclosporine,  tacrolimus, sirolimus and mycophenolate prophylaxis against graft- versus-host disease; and posaconazole, voriconazole, valganciclovir  prophylaxis against infection in patients undergo to transplantation of  haematopoietic stem cells; and to analise the incidence of acute  complications based on adherence.

Method: Retrospective observational study of patients who underwent  allogeneic haematopoietic stem cell transplantation between May 2017  and May 2018. Analyses were carried out between 0 and +100 days  post-engraftment. Whenever possible, adherence to mycophenolate,  tacrolimus, sirolimus, posaconazole, voriconazole and valganciclovir was  evaluated by means of the dispensation records of the Pharmacy  Department of our hospital. To be considered adherent, patients should  have proved an adherence rate equal to or higher than 95%. Adherence  to cyclosporine was determined based on serum levels.  Patients were considered to be non-adherent if their cyclosporine serum  concentrations dropped below 100 ng/mL at any time between days 0  and +100, in the absence of any specific justifying circumstances. The  association between adherence and the inci dence of acute  complications (secondary graft failure, acute graft-versushost disease  and infection) was determined by means of the odds ratio (confidence  interval: 95%).

Results: The study sample was made up by 46 patients, all of whom were started on immunosuppressive cyclosporine prophylaxis; 8.7%   needed to be switched to tacrolimus or sirolimus due to toxicity issues.   All the patients received cyclosporine as prophylaxis against graft-  versus-host disease. Mycophenolate was also administered in 41.3% of  cases. A total of 82.6% patients were found to be adherent to their  prophylaxis treatment against graft failure and 80.4% were found to be  adherent to prophylaxis against graft-versus-host disease. All patients  were adherent to anti-infection prophylaxis. The incidence of acute  graft-versus-host disease in prophylaxisadherent patients was 45.9%,  compared with 55.6% for non-adherent patients (odds ratio 0.68;  confidence interval: 95% 0.157-2.943; p = 0.718).

Conclusions: Patients undergoing allogeneic haematopoietic stem cell transplantation demonstrated acceptable adherence to prophylaxis  against acute complications, although a considerable percentage of  patients was found not to take their medication as prescribed. Correct  adherence to immunosuppressants seems to reduce the risk of  developing acute graftversus- host disease.