Longitudinal Changes in Body Weight and Body Mass Index in Patients with Chronic-Phase Chronic Myeloid Leukemia Treated with Tyrosine Kinase Inhibitors: A Retrospective Observational Study.

BACKGROUND Tyrosine kinase inhibitors (TKIs) have transformed chronic-phase chronic myeloid leukemia (CML) into a chronic condition with excellent long-term survival. As outcomes improve, attention has shifted toward treatment-related metabolic effects and survivorship issues. Body weight and body mass index (BMI) are important indicators of metabolic health; however, the long-term effects of TKIs on these parameters remain incompletely characterized, particularly in real-world settings. This study evaluated longitudinal changes in body weight and BMI in adults with chronic-phase CML treated with TKIs.

METHODS We conducted a retrospective longitudinal observational study at a tertiary care center between January 2016 and December 2023. Adult patients with chronic-phase CML who initiated TKI therapy and had baseline and follow-up weight measurements were included. Patients with major preexisting metabolic conditions or factors likely to confound weight were excluded. Body weight and BMI were assessed at predefined time points up to 7 years. Paired analyses evaluated within-patient changes over time, and stratified analyses were performed according to initial TKI and cumulative exposure patterns.

RESULTS A total of 175 patients were included in the analytic cohort (82.9% male; mean age 39.2 ± 11.7 years). Mean baseline weight was 68.2 ± 14.4 kg, and baseline BMI was 24.6 ± 3.9 kg/m². Weight increased significantly from baseline at 6 months (+4.27 kg), 12 months (+6.00 kg), 18 months (+6.63 kg), and 24 months (+6.41 kg) (all p<0.001). At the last follow-up, the mean weight gain was 6.12 kg (p < 0.001), with 56.9% of patients achieving≥5% weight gain. The temporal pattern showed rapid weight gain during the first 6-12 months, followed by stabilization through 2-3 years with persistent elevation thereafter. Weight and BMI increases were observed across all first-line TKIs and cumulative exposure groups, without statistically significant differences between agents.

CONCLUSION In this real-world cohort of adults with chronic-phase CML, TKI therapy was associated with early and sustained increases in body weight and BMI, largely occurring within the first year of treatment. These changes likely reflect a combination of treatment-related metabolic effects and reversal of cancer-associated catabolism. Given the long life expectancy of patients with CML, routine metabolic surveillance and early lifestyle interventions should be incorporated into long-term management.