THE PSYCHOLOGICAL AND PSYCHIATRIC EFFECTS OF RIL-2 THERAPY - A CONTROLLED CLINICAL-TRIAL

It has been suggested that recombinant interleukin-2 (rIL-2) may cause pyschological and psychiatric problems, although the effects of rIL-2 on its own have not been well documented. To evaluate these effects, 17 patients with advanced colorectal cancer took part in a randomised, parallel group study of rIL-2 with chemotherapy (5-fluorouracil and l eucovorin) versus chemotherapy alone. Patients were assessed regularly by means of various psychometric tests including the Hospital Anxiety and Depression Scale, the Mood Rating Scale, the Mini-Mental State Ex amination, the Digit Symbol Substitution Test, the Trail-Making Test a nd the Benton Revised Visual Retention Test. Rigorous discontinuation criteria were applied to ensure that the effect of time-related variab les did not influence the results. Compared with patients who were giv en chemotherapy alone, patients receiving immunochemotherapy reported reduced energy, impaired confidence, higher depressed mood and more co nfusion. Immunochemotherapy was rated as more distressing than chemoth erapy alone and patients reported a greater incidence of appetite impa irment, weight loss, poor concentration and fever. Cognitive assessmen ts indicated that brain dysfunction can be caused by rIL-2. Compared w ith the control group, patients receiving immunochemotherapy showed si gnificant impairment on Trail Making Test B and the Digit Symbol Subst itution Test. One patient developed repeated transient psychotic episo des. associated with rIL-2 infusions and another regularly became conf used. These effects were not due to sleep deprivation or pyrexia. Trea tment with rIL-2 should not be discarded on psychosocial grounds, alth ough in each case the psychological morbidity and adverse effects on q uality of life need to be balanced carefully against potential therape utic benefits. (C) 1997 John Wiley & Sons, Ltd.