Effect of Controlling Nutritional Status Score (CONUT) and Prognostic Nutritional Index (PNI) on patients after spinal tuberculosis surgery

The controlling nutritional status (CONUT) score and prognostic nutrition index (PNI) are immune-nutritional biomarkers that are related to clinical prognosis. Previous studies have reported using them to predict the prognosis of traumatic brain injury, tumours and other diseases. The purpose of this study was to evaluate the relationship between the PNI and CONUT score and the one-year prognosis of patients with spinal tuberculosis (STB). In this study, the clinical characteristics of 97 patients with STB who underwent debridement and internal fixation at our institution between 2015 and 2020 were retrospectively analysed. According to the receiver operating characteristic (ROC) curve, patients were divided into two groups: a high CONUT group and a low CONUT group. Patients were also divided into a high PNI group and a low PNI group. One-year postoperative prognosis was evaluated by the clinical cure standard. Patients in the favourable group were younger and had a lower rate of pneumonia and urinary tract infection, higher PNI and lower CONUT score than those in the favourable group (P < 0.05). There was an obvious correlation between the PNI and CONUT score (r = − 0.884, P < 0.05). The areas under the curve (AUCs) of the CONUT score and PNI for predicting unfavourable prognosis were 0.888 (95% CI 0.808–0.943, P < 0.001) and 0.896 (95% CI 0.818–0.949, P < 0.001), respectively. The adjusted odds ratios (ORs) of the CONUT score and PNI for predicting unfavourable outcomes were 2.447 (95% CI 1.518–4.043, P < 0.001) and 0.689 (95% CI 0.563–0.843, P < 0.001), respectively. Higher CONUT scores and a lower PNI were associated with adverse outcomes in patients with spinal tuberculosis, and the CONUT score and PNI might be independent predictors of adverse outcomes of spinal tuberculosis postoperatively.