Glucocorticosteroid Induced Bradycardia in Children Receiving Induction Chemotherapy for Acute Lymphoblastic Leukaemia-an Unrecognised Phenomenon

Introduction: Glucocorticoids are an integral part of the treatment protocols of acute lymphoblastic leukaemia. Bradycardia is an under recognised cardiovascular side effect of steroids in children. Though there is published data from the west on this phenomenon, there is very little data on the same in Indian children. We did an analysis to determine the characteristics of bradycardia in our children with acute lymphoblastic leukaemia receiving induction chemotherapy with steroids. The results were compared with the available published western data.

Materials and Methods: All children less than 18 years diagnosed to have Acute Lymphoblastic Leukemia, between January 1, 2018 and December 31, 2019 and received induction chemotherapy with steroids were retrospectively analysed for various parameters of bradycardia . Bradycardia was defined as heart rate less than 110 beats /min, 100 beats/min, 80 beats/min, 70 beats/min and 60 beats/min in the age group of 0-3months, 4-11 months, 1-4 years, 5-11 years and more than 12 years respectively as defined by the PEWS chart. The statistical analysis in the study was done using SPSS 26.0.

Results: Majority of the patients out of a total of 44 children developed decrease in heart rate (HR) after initiation of steroids. Bradycardia was seen in 21 out of 44 (47.7%) children analysed. The mean HR in patients who developed bradycardia was 63 beats/ min. (Range-50-78). The mean decrease in HR was 41 beats/ min. The mean day of onset of bradycardia in our cohort of children was 3.95 days (Range-3-6) and the mean week of recovery was 3 weeks(Range-2-5).

Conclusion: We could demonstrate a decrease in heart rate in our children receiving steroids as a part of our institutional induction regimen. The bradycardia usually occurred in the first week of initiation and recovered by the third week of the protocol treatment.