Combined influence of nutritional and inflammatory status and depressive symptoms on mortality among US cancer survivors: Findings from the NHANES.

Background: Inflammation and nutrition and depression are interrelated, and both are related to changes in mortality rates. We investigated the association of nutritional and inflammation index or depressive symptoms with the risk of all-cause mortality or cause-specific mortality among cancer survivors.

Methods: A prospective cohort of a nationally representative sample of cancer survivors, aged 40 years or older (n = 2331; weighted population, 15 248 255; 67.6 ± 11.0 years; 50.6 % males), were recruited from the US National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Advanced lung cancer inflammation index (ALI) reflected inflammation and nutritional status and Patient Health Questionnaire 9 (PHQ-9) demonstrated depressive symptoms. The independent and joint associations of ALI and PHQ-9 score with mortality outcomes were examined among cancer survivors and Cox regression analysis based on weights was used to calculate the relative risk.

Results: We identified 605 all-cause deaths (cancer, 204; non-cancer, 401) over a median of 6.2 years of follow-up (15,385 person-years; interquartile range, 3.3-9.8 years). High ALI was observed to be consistently associated with lower risks of all-cause (hazard ratio [HR], 0.516; 95 % CI, 0.400-0.667) and non-cancer (HR, 0.414; 95 % CI, 0.291-0.588) mortality compared with low ALI in a series of adjusted models. Meanwhile, lower PHQ-9 score (0-4) was associated with lower risks of all-cause (HR, 0.686; 95 % CI, 0.521-0.903) and non-cancer (HR, 0.686; 95 % CI, 0.474-0.992) mortality compared with higher PHQ-9 score (≥10). Furthermore, joint analyses showed that high ALI was associated with a decreased risk of death among cancer survivors who were not depressive. Specifically, survivors with high ALI but not depressive symptoms had the lowest overall (HR, 0.404; 95 % CI, 0.228-0.715) risks.

Conclusion: In this cohort study, we observed impact of nutritional and inflammatory status and depressive symptoms on mortality among cancer survivors, with the lowest risks of death from both all causes and non-cancer being noted among the combination of high level ALI with no depression.