title: Reduced cardiorespiratory fitness in adult survivors of childhood acute lymphoblastic leukemia.
abstract: BACKGROUND
  Adult survivors of childhood acute lymphoblastic leukemia (ALL) are at increased cardiovascular risk. Studies of factors including treatment exposures that may modify risk of low cardiorespiratory fitness in this population have been limited.
  
  
  METHODS
  To assess cardiorespiratory fitness, maximal oxygen uptake (VO2 max) was measured in 115 ALL survivors (median age, 23.5 years; range 18-37). We compared VO2 max measurements for ALL survivors to those estimated from submaximal testing in a frequency-matched (age, gender, race/ethnicity) 2003-2004 National Health and Nutritional Examination Survey (NHANES) cohort. Multivariable linear regression models were constructed to evaluate the association between therapeutic exposures and outcomes of interest.
  
  
  RESULTS
  Compared to NHANES participants, ALL survivors had a substantially lower VO2 max (mean 30.7 vs. 39.9 ml/kg/min; adjusted P < 0.0001). For any given percent total body fat, ALL survivors had an 8.9 ml/kg/min lower VO2 max than NHANES participants. For key treatment exposure groups (cranial radiotherapy [CRT], anthracycline chemotherapy, or neither), ALL survivors had substantially lower VO2 max compared with NHANES participants (all comparisons, P < 0.001). Almost two-thirds (66.7%) of ALL survivors were classified as low cardiorespiratory fitness compared with 26.3% of NHANES participants (adjusted P < 0.0001). In multivariable models including only ALL survivors, treatment exposures were modestly associated with VO2 max. Among females, CRT was associated with low VO2 max (P = 0.02), but anthracycline exposure was not (P = 0.58). In contrast, among males, anthracycline exposure ≥ 100 mg/m(2) was associated with low VO2 max (P = 0.03), but CRT was not (P = 0.54).
  
  
  CONCLUSIONS
  Adult survivors of childhood ALL have substantially lower levels of cardiorespiratory fitness compared with a similarly aged non-cancer population.
authors: Departments of Pediatrics and Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
authors: Emily S
authors: ES
authors: Tonorezos
authors: Peter G
authors: PG
authors: Snell
authors: Chaya S
authors: CS
authors: Moskowitz
authors: Debra A
authors: DA
authors: Eshelman-Kent
authors: Jennifer E
authors: JE
authors: Liu
authors: Joanne F
authors: JF
authors: Chou
authors: Stephanie M
authors: SM
authors: Smith
authors: Andrea L
authors: AL
authors: Dunn
authors: Timothy S
authors: TS
authors: Church
authors: Kevin C
authors: KC
authors: Oeffinger
mesh_terms: D000293:Adolescent; D000328:Adult; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008962:Models, Theoretical; D010809:Physical Fitness; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000503:physiopathology* / Q000628:therapy; D012042:Registries; D017741:Survivors