The impact of obesity on the risk of progression to MM in MGUS patients

Data presented as a poster at EHA 2026 by Dr Saemundur Rögnvaldsson, haematologist at the  Sahlgrenska University Hospital in Gothenburg and researcher at the University of Iceland, examined the relationship between obesity and the development of multiple myeloma (MM) and its precursor conditions. For this analysis, data were used from the large, population-based iStopMM study in Iceland. 

The analysis leveraged data from a large screening program that evaluated more than half of the Icelandic population aged over 40 years for monoclonal gammopathy of undetermined significance (MGUS). Height and weight measurements and questionnaire data were used to investigate associations between obesity, MGUS prevalence, progression to MM, and changes in disease-related biomarkers over time.

The investigators observed a dose-dependent relationship between obesity and the risk of MGUS, with increasing levels of obesity being associated with a higher likelihood of having this precursor condition. Obesity was also associated with an increased risk of progression from MGUS to more advanced plasma cell disorders, such as MM. Interestingly, individuals who lost weight during follow-up demonstrated a less pronounced increase in M-protein levels over time, suggesting a potentially less aggressive disease trajectory.

Although the observed effects were modest, the findings do suggest that body weight may influence both the development and progression of myeloma precursor conditions. As such, weight management may be a potentially actionable intervention that could help individuals with MGUS or smoldering multiple myeloma influence their disease course.