Pre-operative Neutrophil to Lymphocyte Ratio is Associated With 30 Day Death or Amputation After Revascularisation for Acute Limb Ischaemia

Autores da FMUP

• Andreia Sofia Martins Pires Coelho

  Autor

• João Paulo De Sousa Peixoto

  Autor

• Lia Paula Nogueira Sousa Fernandes

  Autor

Participantes de fora da FMUP

• Coelho, NH
• Augusto, R
• Semiao, C
• Martins, V
• Canedo, M.
• Greg?rio, T.

Unidades de investigação

• Cirurgia e Fisiologia

• Laboratório Associado RISE- Rede de Investigação em Saúde

  

  Investigador

  Fernando Carlos De Landér Schmitt

• Neurociências Clínicas e Saúde Mental

• RISE-Health

  

  Investigador

  Fernando Carlos De Landér Schmitt

Abstract

Objective: Inflammation is an early feature of acute limb ischaemia (ALI), hence the potential prognostic significance of inflammatory biomarkers. This study aimed to assess the value of pre-operative inflammatory biomarkers, specifically the neutrophil to lymphocyte ratio (NLR) and the platelet to lymphocyte ratio (PLR), for predicting an adverse outcome after revascularisation for ALI. Methods: All patients submitted to lower limb revascularisation for Rutherford IIa or IIb ALI at the authors institution between 2009 and 2019 were screened retrospectively. Pre-operative NLR and PLR were analysed, along with other known prognostic factors. Primary outcome was the composite endpoint of 30 day death or amputation. Results: A total of 345 patients were included, 84 of whom suffered the primary outcome (24.3%). The median follow up was 23.1 months (3.1 - 52.2). Higher age (OR 1.05 per year increase, 95% CI 1.01 - 1.09), diabetes (OR 2.63, 95% CI 1.14 - 6.06), Rutherford grade IIb vs. IIa (OR 5.51, 95% CI 2.11 - 14.42), higher NLR (OR 1.28 per unit increase, 95% CI 1.12 - 1.47), and fasciotomy need (OR 3.44, 95% CI 1.14 - 10.34) were independently associated with 30 day death or amputation, whereas pre-operative statin or anticoagulant medication were associated with a risk reduction (OR 0.23, 95% CI 0.53 - 0.96 and OR 0.20, 95% CI 0.05 - 0.84, respectively). PLR did not show an independent effect on this population. Pre-operative NLR presented a good discriminative ability (AUC 0.86, 95% CI 0.82 - 0.90). A cut off NLR level >= 5.4 demonstrated a 90.5% sensitivity and 73.6% specificity for 30 day death or amputation. KaplaneMeier analysis showed that patients with pre-operative NLR >= 5.4 had significantly lower 30 day, six month and one year amputation free survival when compared with those with NLR < 5.4 (64.8 +/- 4.0%, 44.1 +/- 4.1%, and 37.5 +/- 4.1% vs. 98.5 +/- 0.9%, 91.9 +/- 2.0%, and 85.9 +/- 2.5%, log rank p <.001). Conclusion: In this study, higher pre-operative NLR was associated with 30 day death or amputation following intervention for Rutherford grade IIa or IIb ALI. NLR potentially stands as a simple, widely available and inexpensive biomarker that can refine decision making and possibly contribute to ALI morbidity and mortality reduction.

Keywords

• Acute limb ischaemia; Amputation; Biomarkers; Mortality; Neutrophil-lymphocyte ratio; Prognosis