The importance of physical function in patients with multiple myeloma for improving quality of life

To investigate the relationship between physical function and quality of life in multiple myeloma patients.

In this retrospective cross-sectional study, data from patients with multiple myeloma (N = 63), who were referred to the department of Rehabilitation Medicine from October 2017 to May 2018, were reviewed. Patients were excluded based on the following criteria: acute illness, unstable medical conditions, impaired cognition or communication, refusal, or inability to perform the assessment. Physical function was evaluated with the Mini-Balance Evaluation Systems Test (Mini-BESTest), and the European Organization for Research and Treatment of Cancer questionnaires QLQ-C30 and QLQ-MY20 were used for the evaluation of quality of life. To evaluate fatigue and psychotic status, the Fatigue Severity Scale and Beck Depression Inventory were used. Patients were divided into two groups ("good-function group" and "poor-function group"), based on previously studied normative values of the Mini-BESTest. Clinical data was reviewed to interrogate the contributing factors of physical function.

Positive correlations were observed between Mini-BESTest scores and all domains of the QLQ-C30. The Mini-BESTest score was lower in patients with lower serum hemoglobin (r = 0.396, p = 0.001) and albumin levels (r = 0.440, p < 0.001), severe disease-related symptoms (r = - 0.39, p = 0.02), and depression (r = - 0.538, p < 0.001). Further, the poor-function group showed lower hemoglobin (p = 0.024) and albumin levels (p = 0.004).

In patients with multiple myeloma, physical function had a significant relationship with quality of life. Low hemoglobin and albumin levels, severe disease- or treatment-related symptoms, and depression were related to decreased physical function, and thus consequentially exert an effect on quality of life in multiple myeloma patients.