Progressive Relaxation Training in Breast Cancer Patients Receiving Aromatatase Inhibitor Therapy

Aromatase inhibitors (AI) can cause musculoskeletal problems and increased risk of fracture as side effects in breast cancer (BC) survivors. In particular, arthralgia can be observed in almost 50% of patients receiving AI. Moreover; cognitive dysfunctions , decreases in quality of life , anxiety and depression , sleep problems and fatigue can be seen in some of patients receiving AI. According to these possible side effects, evaluation and treatment of such health profiles, pain and symptoms is important in terms of improving the quality of life of the patients.

Progressive muscle relaxation exercises (PRE) were first described by Jacobson in 1938. PRE are in use today with different arrangements and updates. It was well defined physiological, perceptual and behavioral positive findings of muscle relaxation.

PRE was thought to be effective on artralgia, quality of life and anxiety-depression in BC survivors receiving AI.

The patients have been searched from the medical records of brest health center in a local hospital. Necessary permissions to use this data was provided from medical coordinator of the hospital and from the coordinator of Breast Health Center.

The study was conducted as two armed, assessor blinded and randomised controlled trial. BC survivors who are receiving AI were randomised to study (performed PRE) or control (no intervention) group. Eligible patients were provided information about the the study and invited to participate in study via phone call. All assessments and exercise training was carried out in Physiotherapy Department of the same hospital. Outcomes were assessed baseline and at 6th-week intervention Primary endpoint was pain assessment assessed by Brief Pain inventory. Secondary endpoints were quality of life assessed by Functional Assessment of Chronic Illness Therapy and emotional status by Hospital Anxiety and Depression scales.

Statistical analysis Sample size was calculated by using a previous study mentioned the impact of yoga on functional outcomes in breast cancer survivors with aromatase inhibitor-associated arthralgias. The mean and standart deviation data of the FACT-B parameter was used with the power (1-type II error) of 0.80 and a type I error of 0.05. Therefore, it was aimed to recruit at least 20 participants per group. In total, with dropout rate of 30%, it was estimated to recruit 26 patients in each group.

Mean [95% confidence intervals (CI)], standard deviations and frequency rates was analyzed for baseline charecteristics. Group distributions were examined with the Kolmogorov Simirnov test. Groups analysis were performed using the non parametric test methods due to the low number of participants. Mann-Whitney U test for the analysis of quantitative independent data, and Wilcoxon test was used for the analysis of dependent data. Mc-Nemar Test was used for dependent variables and Chi-Square test was used for independent variables in the analysis of qualitative data. Cohen's Formula used for calculating efect size of differences between and within the groups. Figures are performed by the SPSS graphics. P value <0.05 was considered as significant.

Inclusion criteria

• Using Aromatase Inhibitors for more than 6 months
• Diagnosis of breast cancer stage 1-3
• Postmenopausal woman aged under 70 years and with hormone-receptor positive
• Approval of physician for participating in PRE program

Exclusion criteria

• Participation on a regular physical training in the previous 6 months period
• Communication problems
• Neurological or ortopedical problems
• Presence of lyphedema diagnosis