Analysis of influencing factors of dismal prognosis in severe tuberculous meningitis

Abstract

Objective To investigate the influencing factors related to long ⁃ term prognosis in patients with severe tuberculous meningitis (TBM). Methods One hundred sixty⁃three patients with severe TBM admitted to Tianjin Haihe Hospital from June 2012 to December 2019 were included. After one year of anti⁃tuberculous therapy, the prognosis of the patients was evaluated by modified Rankin Scale (mRS). Univariate and multivariate stepwise Logistic regression analyses were used to analyze the influencing factors of long ⁃ term dismal prognosis of severe TBM. The predictive value was evaluated by receiver operating characteristic (ROC) curve. Results In the dismal prognosis group (mRS > 2, n = 68), patients' age (t = ⁃ 5.884, P = 0.000), hypertension (χ2 = 15.769, P = 0.000), coronary heart disease (adjusted χ2 = 6.785, P = 0.009), limb weakness (χ2 = 9.544, P = 0.002), hydrocephalus (χ2 = 23.004, P = 0.000), cerebral infarction (χ2 = 17.417, P = 0.000), cerebrospinal fluid (CBF) lactic acid level (Z = ⁃ 2.405, P = 0.016) were higher than those in favourable prognosis group (mRS ≤ 2, n = 95), while Glasgow Coma Scale (GCS) score on admission was lower than that in favourable prognosis group (Z = ⁃ 6.750, P = 0.000). Logistic regression showed that old age (OR = 1.064, 95%CI: 1.031-1.098; P = 0.000) and high CSF lactic acid level (OR = 1.404, 95%CI: 1.065-1.852; P = 0.016) were risk factors for long⁃term dismal prognosis of severe TBM, and high GCS score on admission was a protective factor for long⁃term favourable prognosis of severe TBM (OR = 0.539, 95%CI: 0.405-0.716; P = 0.000). ROC curve showed the cut ⁃ off value of age for predicting long ⁃ term dismal prognosis of severe TBM on admission was 48.50 years, the area under the curve (AUC) was 0.743 (95%CI: 0.665-0.822, P = 0.000), the sensitivity was 63.20% and the specificity was 76.80%. The cut⁃off value of GCS score was 12.50, the AUC was 0.802 (95%CI: 0.732-0.871, P = 0.000), the sensitivity was 58.80% and the specificity was 86.30%. The cut⁃off value of lactic acid level in CSF was 6.99 mmol/L, the AUC was 0.611 (95%CI: 0.517-0.704, P = 0.016), the sensitivity was 42.60% and the specificity was 91.60%. The AUC of the combined application of the 3 indexes was 0.892 (95%CI: 0.841-0.944, P = 0.000), the sensitivity was 80.90% and the specificity was 88.40%, which showed that the prediction efficiency was better than that of a single index. Conclusions Advanced age and high lactic acid level in CBF are risk factors for dismal long⁃term prognosis of severe TBM. High GCS score on admission is a protective factor. Clinicians should focus on these factors to improve the prognosis of patients.

Keywords

• tuberculosis, meningeal
• prognosis
• risk factors
• logistic models