BSPED2008 Oral Communications Late effects (4 abstracts)
Aim: There is emerging evidence that survivors of BMT not only suffer long term endocrine sequelae, but also have an increased risk of cardiovascular disease. The UKCCSG guidelines suggest that BMT survivors should be monitored for cardiac and lung toxicities of previous treatments using cardiac ECHOs and pulmonary function tests (PFTs). We aimed to examine body composition, aerobic fitness, ECHOs and PFTs in adolescent and young adult survivors on GHTx.
Method: We enrolled 24 young people (12F). Their mean age was 16.6 (range 9.424) years. They were a mean of 8.3 (range 2.316) years from BMT.11 were pubertal, and 13 post-pubertal. We measured body composition by DEXA, aerobic fitness by VO2 peak using an inclined treadmill. This is an individuals maximal ability to utilise oxygen during progressive exercise and is usually adjusted for body weight. Forced vital capacity standard deviation score (FVCSDS) is adjusted for height, gender and age.
Results: All results expressed as mean (SD).
|% Fat by DEXA male||% Fat by DEXA female||VO2 peak (ml/kg)||Fractional shortening %||FVC SDS||Height SDS||Lean mass (kg)|
|Survivors||23.2 (13.6)||40.9 (7.9)||33.5 (7.9)||37.3 (10.1)||−2.48 (1.72)||−1.0 (1.1)||34.8 (10.0)|
|Normal reference||16.0 (4.0)||29.8 (5.1)||44.5 (5.0)||>29||0 (1)||0 (1)||51.5 (7.4)|
Survivors have high body fat despite a normal BMI SDS. Females have a higher body fat than males (P<0.05) but aerobic fitness is similar. Body composition abnormalities worsen during puberty. One male and 5 females (30%) had VO2 peak values below the healthy range for their age and gender. VO2 peak is highly correlated with lean mass (r=0.83, P<0.000) and % body fat was significantly negatively correlated with VO2/kg (r=−0.66, P=0.008). Adjustment of VO2 for body weight underestimates aerobic fitness in this group who have increased body fat with reduced lean mass. About 6 of 14 survivors had FVC SDSs below −3 suggesting restrictive lung deficits. About 21% had reduced fractional shortening due to previous anthracyline therapy and total body irradiation.
Conclusion: BMT survivors have a high rate of abnormal body composition, reduced aerobic fitness, restrictive lung deficits and ECHO abnormalities. Future intervention strategies should aim to maximise cardio respiratory health and correct body composition abnormalities.