Ontario, CanadaTreatment for acute lymphoblastic leukemia (ALL) as a child may
increase the risk for obesity in adulthood, and a new study suggests that
cranial irradiation may be a factor. The results (abstract 13) were presented
at the 7th International Conference for Long-Term Complications of Treatment of
Children and Adolescents for Cancer, hosted by Roswell Park Cancer Institute.
"Obesity is a serious health condition," said Kevin
Oeffinger, MD, Department of Family Practice and Community Medicine, The
University of Texas Southwestern Medical Center at Dallas. "It can lead to
other serious health conditions such as diabetes and hypertension. We should
know if the treatment for ALL predisposes this population to additional health
risks and help with appropriate interventions."
This study evaluated 1,765 adult survivors of ALL who
participated in the Childhood Cancer Survivor Study (CCSS). The CCSS is a
resource designed to investigate the long-term effects of cancer treatment
among 5-year survivors of childhood and adolescent cancer. The ALL survivors
were compared with 2,565 cancer-free siblings; 47,555 participants from the
National Health Interview Study (NHIS) were also studied.
The mean age was 24.1 years for the leukemia survivors and
29 years for the siblings. The survivors’ mean age at diagnosis was 7.5 years
(range, 0.1 to 20.8), and the study was conducted a mean of 17.1 years after
their diagnosis (range, 7.4 to 27.5). The survivor group was 49% female and the
siblings were 53% female.
Participants were asked to provide their current height and
weight. Using these self-reported figures, a body mass index (BMI) was
calculated to determine the obesity rate. The national standard was used in
which a BMI of 30 or greater represents obesity and 25 to 29.9 represents
After adjusting for sex and age, there were no significant
differences in weight between the sibling group and the NHIS group. However,
there were differences for the survivor population, compared with their
siblings, depending on the type of treatment they received.
The age- and race-adjusted odds ratio for obesity for ALL
survivors treated with chemotherapy and cranial radiation of 20 Gy or more,
compared with siblings, was 2.59 for females (P < .001) and 1.86 for
males (P < .01). In particular, for females diagnosed between 0 and 4
years of age, the risk, compared with siblings, was 3.81 (P < .001).