A Randomized Trial Investigating an Exercise Program to Prevent Osteoporosis and Motor Problems during Treatment for Childhood Acute Lymphoblastic Leukemia.

Reduction in bone mineral density (BMD), fractures, altered body composition, deteriorated motor performance and impaired passive ankle dorsiflexion are side-effects of chemotherapy during childhood acute lymphoblastic leukemia (ALL). Because only scarce information is available on the value of regular exercise to prevent these side-effects, we performed a randomized trial to investigate the effects of intervention with an exercise program. At diagnosis 51 ALL patients (median age: 5.4 years) were randomized into a group receiving intervention (including twice-daily high-intensity weight-bearing activities throughout the two-year during treatment period), or a control group receiving standard care. BMD of total body (BMD_TB) and lumbar spine (BMD_LS) and body composition parameters were measured using dual energy X-ray absorptiometry (DEXA). We measured motor performance with the Bayley Scales of Infant Development and the Movement-ABC, and passive ankle dorsiflexion with a goniometer. The investigators were blinded to the randomization. Repeated measurements analysis (ANOVA) was used. BMD decreased equally in the intervention and control group during treatment (delta-BMD_TB: −0.75 SDS vs −0.96 SDS, p=0.65 and delta-BMD_LS: −0.15 SDS vs −0.04 SDS, p=0.83), and increased equally during the year after treatment (delta-BMD_TB: 0.42 SDS vs 0.35 SDS, p=0.70 and delta-BMD_LS: 0.10 SDS vs 0.14 SDS, p=0.84). Body-fat increased during treatment in both groups (delta-fat: 1.04 SDS vs 1.56 SDS, p=0.25). In the intervention group a more rapid decline of body-fat was observed during the year after completion of therapy than in the control group (delta-fat: −1.08 SDS vs −0.49 SDS, p=0.01). Lean body mass (LBM) of both groups decreased equally during treatment (delta-LBM: −0.61 SDS vs −0.12 SDS, p=0.16) and increased equally the year after stop of treatment (delta-LBM: 0.29 SDS vs 0.22 SDS, p=0.66). Both groups showed similar changes in passive ankle dorsiflexion mobility (−5.2º vs −4.6º, p=0.76) and motor performance (0.37 SDS vs 0.68 SDS, p=0.44) during treatment. Adherence to the exercise program varied considerably: 11% of the patients performed exercises daily, 37% more than once a week, 16% once weekly and 36% less than once a week. The exercise program was not more beneficial in preventing reduction in BMD, motor performance and passive ankle dorsiflexion than standard care, most likely due to unsatisfactory compliance. However, the faster recovery after stop of treatment of the excess of body-fat in the intervention group than in the control group may be due to the educational effect of the intervention program.