INVESTIGATING THE EFFECTS OF THE PROGRESSIVE MUSCLE RELAXATION-GUIDED IMAGERY COMBINATION ON PATIENTS WITH CANCER RECEIVING CHEMOTHERAPY TREATMENT: A SYSTEMATIC REVIEW OF RANDOMIZED CONTROLLED TRIALS

Background: Previous systematic reviews indicate that progressive muscle relaxation (PMR) and guided imagery (GI) are both effective interventions to decrease the psychological impact and to alleviate the adverse events in cancer patients undergoing chemotherapy treatment. To date, no review studies have investigated the effectiveness of a combination of PMR and GI. Aim: To systematically review the current state of knowledge regarding the effects of the PMR GI combination on cancer patients receiving chemotherapy. Methods: A search for relevant records was carried out in four electronic databases (AMED, Cochrane Library, Pubmed and Scopus). After removing the duplicates 342 publications were screened and 71 were considered as potentially relevant. The flow of information of this study was in line with the PRISMA statement. Original articles investigating the application of both PMR and GI through a randomized trial on patients receiving chemotherapy were included. Those using PMR or GI alone and those combining other techniques together with PMR and GI were excluded. The trials' quality was assessed using the Jadad Scale. Results: Eight papers reporting the results of seven independent trials were finally included. All of them included only breast cancer patients, apart from a single trial using a mixed sample of breast and prostate cancer patients. Seven of the included trials reported beneficial effects on mental state (mood, anxiety, and depression) and on toxicity (nausea and vomiting). Three trials reported an effect on biomarkers (heart rate, blood pressure, cortisol, and immunity). Four trials scored three of five points on the Jadad Scale, two trials scored two points and a single trial scored zero. Conclusions: Independent trials indicate that the PMR GI combination is an effective way to tackle the impact of nausea and vomiting and to improve patients' mental state. However, studies involving other types of primary tumors would be useful because seven of the eight clinical trials only included breast cancer patients. Future research on the identification of potential effects on disease-related parameters (e.g., cytokines and disease recurrence) and on patient survival is highly needed.