Purpose: Although many studies have demonstrated that smoking, alcohol, obesity, and insulin resistance are risk factors for cancer, the role of those factors on cancer survival has been less studied.
Patients and methods: The study participants were 14,578 men with a first cancer derived from a cohort of 901,979 male government employees and teachers who participated in a national health examination program in 1996. We obtained mortality data for those years from the Korean Statistical Office. We used a standard Poisson regression model to estimate the hazard ratio (HR) for survival in relation to smoking, alcohol, obesity, and insulin resistance before diagnosis.
Results: Poor survival of all cancer combined (HR, 1.24; 95% CI, 1.16 to 1.33), cancer of the lung (HR, 1.45; 95% CI, 1.15 to 1.82), and cancer of the liver (HR, 1.36; 95% CI, 1.21 to 1.53) were significantly associated with smoking. Compared with the nondrinker, heavy drinkers had worse outcomes for head and neck (HR, 1.85; 95% CI, 1.23 to 2.79) and liver (HR, 1.25; 95% CI, 1.11 to 1.41) cancer, with dose-dependent relationships. Patients with a fasting serum glucose level above 126 mg/dL had a higher mortality rate for stomach (HR, 1.52; 95% CI, 1.25 to 1.84) and lung (HR, 1.48; 95% CI, 1.18 to 1.87) cancer. Higher body mass index was significantly associated with longer survival in head and neck (HR, 0.54; 95% CI, 0.39 to 0.74) and esophagus (HR, 0.44; 95% CI, 0.28 to 0.68) cancer.
Conclusion: Prediagnosis risk factors for cancer development (smoking, alcohol consumption, obesity, and insulin resistance) had a statistically significant effect on survival among male cancer patients.