Effect of imatinib on the height of children with chronic myeloid leukemia in the chronic phase

Objective: To evaluate the effect of imatinib on growth impairment in children with chronic myeloid leukemia (CML-CP) in the chronic phase. Methods: From July 2018 to July 2019, questionnaires were distributed to CML children aged <18 years at the time of diagnosis who were receiving imatinib for at least 3 months or to their parents in China. The height-for-age standard deviation score (HtSDS) and the difference of standard deviation integral (△HtSDS) were used to explore the change in height with imatinib therapy. Results: The data of 238 respondents were included; 138 (58.0% ) respondents were men. The median age at the first diagnosis of CML was 11.0 years (range, 1.4-17.9 years) , and 93 (39.0% ) respondents were at the prepuberty stage. At the time of completing the questionnaires, the median age was 15.0 years (range, 2.0-34.0 years) . The median duration of imatinib therapy was 28 months (range, 3-213 months) . Among all the respondents, the mean HtSDS when completing the questionnaires (-0.063±1.361) was significantly lower than that at the time of starting imatinib treatment (0.391±1.244) (P<0.001) . Total 71.0% respondents showed growth impairment that was more common in those starting imatinib therapy at prepubertal age than in those starting at pubertal age. Multivariate analysis showed that younger at the start of imatinib therapy (P<0.001) and longer duration of imatinib therapy (P<0.001) were significantly associated with severe growth impairment on imatinib therapy. Conclusions: Imatinib induced growth impairment in children with CML-CP. Younger the age of initiation and longer the duration of imatinib therapy, more obvious the effect of imatinib on growth impairment.