Survival outcome
OS was significantly longer in PN patients than in the RN cohort (see Figure 3). The mean OS times were 165.3 and 159.9 (95% CI: 162.6-168.0 vs. 155.6-164.2; p <0.05) months in the PN and RN groups, respectively. There was no significant difference in mortality between groups when the patients were divided by age (≤49, 50-64, and ≥65; p =0.12). Although the mean OS was shorter in patients with comorbidities, including hypertension, diabetes mellitus, coronary artery disease, and hyperlipidemia, than in those without comorbidities (160.2 vs. 164.2 months), this difference was not statistically significant (p =0.41; see Table 5).
A Cox proportional hazards model was used to evaluate the potential predictors, and the results are shown in Table 6. Univariate analysis revealed that OS was significantly associated with RN (HR: 3.3, 95% CI: 1.1-9.8; p =0.03). In multivariate analysis, RN was an independent negative prognostic factor for OS (HR: 6.3, 95% CI: 1.4-27.9;p =0.01).