In these analyses, 14 factors were associated with IL-6 (P-value ≤0.20): age (P <  0.0001), sex (P = 0.04), current BMI and BMI at 20 years of age (P = 0.02 and 0.04, respectively), marital status (P = 0.02), household income (P = 0.02), KPS (P <  0.0001), Charlson Comorbidity Index (P <  0.0001), diabetes (P = 0.06), cancer site (P = 0.0004), TNM stage (P = 0.007), tobacco consumption (P = 0.0008), history of alcohol abuse (P = 0.03) and sleep discturbance (P = 0.20). Here, IL6 is linked to cancer.