Physical function in patients newly diagnosed with multiple myeloma; a Danish cohort study

BACKGROUND: Multiple myeloma is a cancer in the bone marrow causing bone destruction. Patients experience various symptoms related to the disease and/or treatment, such as pain and fatigue, leading to poorer quality of life. The symptom burden might affect physical function and physical activity levels, posing a risk of physical deterioration. The aim was to investigate whether physical function in newly diagnosed patients with multiple myeloma differs from the reference values of the normal population and other cancer patients. METHODS: The study is a cross sectional descriptive analysis of a prospective cohort of 100 patients newly diagnosed with multiple myeloma. Four physical function tests were carried out; Six-Minute-Walk-Test, Sit-to-Stand-Test, grip strength and knee extension strength. Age and gender specific results of physical function from the multiple myeloma population were compared to normative data and to data from other cancer populations. RESULTS: Of the 100 patients included, 73% had bone disease and 55% received pain relieving medicine. Mean age was 67.7 years (SD 10.3). Patients with multiple myeloma had significantly poorer physical function compared to normative data, both regarding aerobic capacity and muscle strength, although not grip strength. No differences in physical function were found between patients with multiple myeloma and other cancer populations. CONCLUSIONS: Physical function in newly diagnosed Danish patients with multiple myeloma is lower than in the normal population. Exercise intervention studies are warranted to explore the value of physical exercise on physical function. TRIAL REGISTRATION: ClinicalTrials.gov, ID NCT02439112, registered 8 May 2015.