Originally published by our sister publication Clinical Oncology News

Among adolescents and young adults (AYAs) being treated for acute lymphoblastic leukemia (ALL), those who are overweight or obese have lower survival rates, according to a new study. The data, published in Blood Advances (2023 Jul 11. doi:10.1182/bloodadvances.2023009976), are concerning, especially given the growing public health threat of obesity.

“We have known for roughly 15 years that obesity affects survival in pediatric patients treated for ALL, and more recently, we are recognizing a similar relationship in adult populations,” said lead study author Shai Shimony, MD, an advanced fellow at the Dana-Farber Cancer Institute, in Boston. “But we wanted more granular data on this, to understand why this correlation exists, and how dependent it is on age.”

In the study, Dr. Shimony and colleagues collected data from 388 AYAs aged 15 to 50 years, with a mean age of 24 years, who were being treated on Dana-Farber Consortium pediatric regimens for ALL from 2008 to 2021. The researchers examined the relationship between body mass index, age, toxicities and treatment outcomes in the cohort, aiming to identify any correlations or trends.

In total, 53.3% of AYAs included in the study had a normal BMI and 46.6% were classified as overweight or obese. Patients with an overweight or obese BMI exhibited a higher rate of non-relapse mortality (11.7% vs. 2.8%; P=0.006), a lower event-free survival rate (63% vs. 77% at four years; P=0.003) and a worse overall survival (64% vs. 83% at four years; P=0.0001) compared with those with normal BMIs. The researchers found equivalent overall survival among younger (15-29) and older (30-50) AYAs with normal BMIs (83% vs. 85% at four years; P=0.89). 

Regarding toxicity, AYAs with an overweight or obese BMI experienced higher rates of grade 3/4 hepatotoxicity (60.7% vs. 42.2%; P=0.0005) and grade 3/4 hyperglycemia (36.4% vs. 24.4%; P=0.014) but had comparable rates of hypertriglyceridemia (29.5% vs. 24.4%; P=0.29). 

In the multivariable model for survival, higher BMI was associated with worse survival, while age was not associated with survival, and elevated triglycerides were associated with improved survival. Elevated triglycerides reflect the activity of one of the principal chemotherapy medications, asparaginase, included in the regimen, and this finding suggests the possible use of an affordable lab test as a biomarker of treatment efficacy. However, the researchers noted that this should not be viewed as an adverse finding.

“This study highlights the association between elevated BMI and increased treatment-related toxicity, non-relapse mortality, and decreased overall survival in AYAs undergoing treatment for ALL with intensive pediatric regimens,” Dr. Shimony noted.

—Kate O’Rourke

Dr. Shimony reported no relevant financial disclosures.