Preoperative Neutrophil to Lymphocyte Ratio, Platelet to Lymphocyte Ratio, and Mean Platelet Volume as Predictors of 1-Year Mortality in Patients Undergoing an Open Repair of Abdominal Aortic Aneurysms: A Retrospective Study.

OBJECTIVES

To investigate if preoperative neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), or mean platelet volume (MPV) could be used to predict 1-year mortality in patients undergoing open abdominal aortic aneurysm (AAA) repair.

METHODS

We retrospectively reviewed 382 patients who underwent open AAA repair between January 2008 and July 2019. We divided the patients into two groups based on 1-year mortality and compared the preoperative NLR, PLR, and MPV. The patients were then classified into tertiles based on their preoperative NLR (first tertile: <2.41 ( = 111); second tertile: 2.41 ≤ NLR ≤ 6.07 ( = 111); and third tertile: >6.07 ( = 112)). We compared the incidence of mortality and morbidity across the aforementioned tertiles. We performed a stepwise logistic regression analysis to evaluate the predictors for mortality. An additional subgroup analysis was performed by dividing the cases into non-ruptured and ruptured cases.

RESULTS

The preoperative NLR was significantly higher in the non-survivor group than in the survivor group (10.53 ± 7.60 vs. 5.76 ± 6.44, respectively, = 0.003). The PLR and MPV were similar between the groups (145.35 ± 91.11 vs. 154.20 ± 113.19, = 0.626, 9.38 ± 1.20 vs. 9.11 ± 1.39, = 0.267, respectively). The incidence of 1-year mortality was 2.7%, 9.0%, and 14.3% in the first, second, and third NLR tertiles, respectively ( = 0.009). Higher NLR (odds ratio 1.085, 95% confidence interval 1.016-1.159, = 0.015) and ruptured AAA (odds ratio 2.706, 95% confidence interval 1.097-6.673, = 0.031) were the independent predictors of 1-year mortality in all patients. Moreover, the preoperative NLR was significantly higher in the ruptured AAA than in the non-ruptured AAA group (11.17 ± 7.90 vs. 4.10 ± 4.75, < 0.001). In subgroup analysis, preoperative NLR (odds ratio 1.144, 95% confidence interval 1.031-1.271, = 0.012) and PLR (odds ratio 0.986, 95% confidence interval 16 0.975-0.998, = 0.017) was an independent predictor for 1-year mortality in ruptured cases.

CONCLUSIONS

We demonstrated an independent relationship between the preoperative NLR and 1-year mortality in patients undergoing open AAA repair, besides PLR and MPV. Furthermore, the NLR and PLR had predictive power for 1-year mortality in ruptured cases.