Muscle Fat Infiltration in Patients with Multiple Myeloma: A Case-Control Study

Sarcopenia in patients with hematologic malignancies has gained attention. However, muscle fat infiltration in patients with multiple myeloma (MM) has not been well studied. In this study, we showed the prevalence of computed tomography (CT)-based muscle fat infiltration in newly diagnosed MM patients.

A total of 966 participants, 138 MM patients and 828 controls, who underwent CT examinations were involved in this study. Clinical parameters, such as participants' age, sex, weight, height and laboratory test results, such as serum lipids, liver and renal function, were collected. The CT radiation attenuation of the bilateral erector spinae (ESRA) muscles and cross-sectional axial skeletal muscle (SMRA) at the medium level of the T11 vertebra were measured on axial CT images. Logistic regression analyses were performed to assess the association between MM and the risk of low muscle CT attenuation. Receiver operating characteristic curve was used to show the performance of muscle CT attenuation in identifying MM.

Muscle CT attenuation in the MM group was significantly lower than in controls (p < 0.001). The prevalence of low muscle CT attenuation in MM patients was significantly higher than those in controls (66.7% vs 19.6%; 60.1% vs 20.4%, p < 0.001). MM was significantly associated with the risk of low ESRA (<36 HU) (odds ratio (OR)  = 15.11, 95% confidence interval (CI): 7.76-29.39) and SMRA (<34 HU) (OR = 12.00, 95% CI: 5.91-24.39) in the fully adjusted models. Subgroup analyses in men and women both showed similar results with the overall population. The area under the curve was 0.827 for ESRA and 0.790 for SMRA in identifying MM patients.

Muscle fat infiltration is common in patients with MM. MM is significantly associated with the risk of muscle fat infiltration.