Factors Affecting Cancer Mortality in Young Adults: Findings from a Prospective Cohort Study.

Background/objectives: Cancer incidence in young adults or those aged 15-49 years old has increased during the past decade. Knowledge about the risk factors for cancer-related deaths in young adults is limited, particularly in low- and middle-income countries (LMICs).

Methods: This analysis was based on the Hanoi Prospective Cohort Study, an ongoing study of 39,401 participants aged 15 or older in Northern Vietnam in the 2007-2019 period. A Cox proportional hazard regression model was used to calculate the hazard ratio (HR) and 95% confidence intervals (95% CIs) for the association between potential factors and the risk of cancer-related deaths.

Results: With a median follow-up of 11.01 years, we identified 164 deaths in young adults out of 554 total deaths. Overall, family history of cancer (HR = 7.34; 95% CI: 3.30-16.36), drinking alcohol (HR = 1.82; 95% CI: 1.18-2.81), and smoking (HR = 2.22; 95% CI: 1.36-3.63) were found to be risk factors, while drinking coffee was found to be a protective factor (HR = 0.49; 95% CI: 0.24-1.00) for cancer-related deaths in young adults. Young male adults were found to be at a higher risk due to excessive cigarette smoking (HR = 1.91; 95% CI: 1.00-3.68) and alcohol consumption (HR = 2.15; 95% CI: 1.32-3.53) than those aged 50 years and older (HR = 1.36 and 95% CI: 0.96-1.93 and 1.27 and 95% CI: 0.97-1.67, respectively). The risk of death from cancer in women compared with men in the young population was twice as high as that in the older population (HR = 1.18 and 95% CI: 0.72-1.94 vs. 0.47 and 95% CI: 0.35-0.63, respectively).

Conclusions: Our data suggest that the young Vietnamese population is vulnerable to the risk of cancer-related deaths and that cancer in women will increase rapidly in the future.