Abstract: Objective To investigate the correlation between blood lipid levels and survival prognosis for the gastric cancer patients undergoing operation. Methods A total of 837 gastric cancer patients who underwent gastrointestinal surgery in department of Xijing Hospital, Air Force Medical University from May 2020 to May 2021 were selected as the study objects. The relationship between Serum levels of total cholesterol (TC), triglycerides (TG), high⁃density lipoprotein cholesterol (HDL⁃C), low⁃density lipoprotein cholesterol (LDL⁃C) and overall survival (OS) in patients with gastric cancer were analyzed by the Cox regression and the restricted cubic spine analysis. Results The survival analysis showed that the patients with TC≥5.2 mmol/L had a risk of death 56.8% higher than the patients with TC<5.2 mmol/L (HR=1.568, 95% CI:1.159~2.121), and the risk of death in patients with LDL⁃C≥3.4 mmol/L was 95.7% higher than that in patients with LDL⁃C<3.4 mmol/L (HR=1.957, 95% CI: 1.440~2.660). However, TG and HDL⁃C were not associated with OS (P>0.05). The restricted cubic spine analysis showed that there was a U⁃shaped relationship between TC and OS. When TC level was less than 4.36 mmol/L, the survival risk of patients decreased with the increase of TC level, and the lowest risk was reached at TC=4.36 mmol/L. The risk increased with the increase of TC level at > 4.36 mmol/L (P for nonlinear=0.006). There was a J⁃shaped relationship between LDL⁃C and OS. When LDL⁃C level was in the low range, the risk was relatively stable, and the risk increased rapidly until LDL⁃C=2.57 mmol/L (P for nonlinear=0.024), and no correlation was found between TG and HDL⁃C level and OS (P>0.05 for both). Subgroup analysis showed that TC and LDL⁃C were more significantly associated with OS in male patients, age>50 years old, BMI<18.5 kg/m2, smoking history, no history of coronary heart disease and alcohol consumption (all P<0.05), except for the association between TG and OS observed in gastric cancer patients with a smoking history, there was no significant correlation between TG and HDL⁃C levels and OS in other subgroups (all P>0.05). Conclusions High levels of LDL⁃C and TC are closely associated with poor clinical prognosis in gastric cancer patients, which can be used as an important indicator for postoperative prognostic assessment of patients with gastric cancer.

Key words: Gastric cancer')">Gastric cancer, Surgery, Lipids, Survival prognosis, Retrospective cohort study