TOPLINE:

Among older adults with pancreatic ductal adenocarcinoma (PDAC), prediagnosis diabetes was associated with shorter survival, but BMI and physical activity throughout adulthood showed no relationship with survival.

METHODOLOGY:

• Both diabetes and excess body weight are risk factors for PDAC, but their impact on survival is unclear. No studies have examined the relationship between body weight or exercise patterns throughout adulthood and pancreatic cancer survival.
• Researchers examined data from the National Institutes of Health (NIH)-American Association of Retired Persons Diet and Health study, a large prospective cohort study of adults aged 50-71 years begun in 1995. Over 24 years of follow-up, 2522 participants were diagnosed with PDAC and could be included in the analysis.
• Data on exposures before diagnosis (self-reported diabetes; BMI at ages 18, 35, 50, and 51-70 years; and leisure-time physical activity at multiple life stages) were collected using questionnaires. Multivariable Cox proportional hazards models estimated hazard ratios (HRs) for PDAC-specific mortality.
• Four trajectories for BMI were identified for men and women; most participants moved into a higher BMI category over time, but 44.5% of men and 38.5% of women maintained a normal weight. Five trajectories for physical activity were identified, though most participants were at least moderately active throughout adulthood.

TAKEAWAY:

• Overall, 80.2% of participants died from PDAC. Prediagnosis diabetes was associated with reduced survival vs no diabetes (HR, 1.36), after adjustment for factors such as age, disease stage, alcohol intake, and smoking. Similar associations were observed in men and women (HRs, 1.41 and 1.33, respectively).
• Trajectories for BMI and physical activity showed no significant association with survival in the overall analysis.
• Among patients with unknown cancer stage (n = 1385), obesity at age 18 years was associated with reduced survival overall (HR, 1.56), as were overweight and obesity at ages 50-71 years (HR, 1.33 for overweight and 1.55 for obesity; P for trend < .01). But because of the importance of stage in survival, the authors noted, those findings should be interpreted with caution.

IN PRACTICE:

This study offers “compelling evidence” that prediagnosis diabetes is associated with reduced survival among patients with PDAC, the authors wrote. “However,” they added, “our findings do not strongly support an association between prediagnosis BMI or [physical activity] throughout the adult life course and PDAC survival.” Future studies including biomarkers are needed to better understand the biology underlying the association between prediagnosis diabetes and poorer survival, they concluded.

SOURCE:

This study, led by Noah C. Peeri, PhD, MPH, Memorial Sloan-Kettering Cancer Center, New York City, was published online in JNCI Cancer Spectrum.

LIMITATIONS:

This study population primarily consisted of non-Hispanic White participants, limiting generalizability to other ethnic groups. BMI trajectories were calculated using only four time points, and weight and physical activity data were self-reported, introducing potential measurement error and recall bias.

DISCLOSURES:

This study received support from the Intramural Research Program of the NIH. The authors reported no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.