The impact of dietary selenium on all-cause mortality in lung cancer: insights from the national health and nutrition examination survey

<bold>Introduction</bold> Lung cancer is the leading cause of cancer mortality (1.8 million deaths; 18.0% of all cancer deaths) in 2020 worldwide. Several laboratory studies have demonstrated the potential anticarcinogenic effects of selenium (Se), but the epidemiological findings have been inconclusive. <bold>Aims</bold> To explore whether dietary Se can reduce all-cause mortality in patients with lung cancer <bold>Methods</bold> We used the NHANES database to investigate the effect of dietary Se on the all cause mortality of lung cancer patients. Cox regression models were performed with PROC SURVEYPHREG to identify the association of dietary Se and all-cause mortality in patients with lung cancer. Multivariable regression was adjusted by different variable combinations. <bold>Results</bold> Figure 1 shows the flow diagram of the study population selection process. A total of 91,351 interviewed subjects were identified in 1999-2018 (9 cycles) from NHANES. Only 44,475 participants aged ≥20. After excluding 111 participants with missing information on smoking status and death, finally, 44,364 participants were included for the subsequent analyses. (Figure 1). The multivariable model revealed that higher dietary Se was associated with a significantly lower risk of allcause mortality (adjusted hazard ratio [aHR] = 0.34, 95%CI: 0.18-0.67, p-value = 0.004). In addition, compared to the lowest level, higher levels of Se intake were significantly associated with lower risk of death (aHR = 0.42 to 0.30) (Figure 2). <bold>Conclusions</bold> Dietary Se is associated with reduced all-cause mortality in lung cancer patient. Futher studies are needed to validate the anti-cancer effect of Se.