Ying Zhang, Manling Zhang, Meixia Zhang
Early neurological deterioration (END) was common after minor subcortical infarction, but prediction was complicated by heterogeneous mechanisms, including intrinsic small-vessel disease and branch atheromatous disease (BAD). A retrospective analysis included 240 patients admitted within 24 h of symptom onset with a National Institutes of Health Stroke Scale (NIHSS) score of 5 or less. END was defined as an increase of at least 2 NIHSS points within 72 h after admission. The primary logistic model retained admission systolic blood pressure (SBP) as a continuous variable and included baseline NIHSS, neutrophil-to-lymphocyte ratio (NLR), and vascular stenosis of at least 50%. A three-knot restricted cubic spline was used to assess SBP nonlinearity. Internal validation used 1,000 bootstrap resamples, and calibration used bootstrap out-of-bag predictions. END occurred in 54 of 240 patients (22.5%). For each 10 mmHg increase in SBP, the adjusted odds ratio (OR) was 1.19 (95% confidence interval [CI], 1.04-1.36); the corresponding ORs were 1.36 (1.04-1.78) per NIHSS point, 1.34 (1.10-1.62) per NLR unit, and 2.21 (1.13-4.31) for stenosis. Evidence of SBP nonlinearity was absent (P = 0.595). The primary model had an apparent area under the receiver operating characteristic curve (AUC) of 0.762 (95% bootstrap CI, 0.686-0.826), an optimism-corrected AUC of 0.741, and an out-of-bag Brier score of 0.158. MRI-only, parent-artery-stenosis exclusion, and ischemic-END analyses were directionally consistent. Suspected BAD was present in 83.3% of END cases and materially increased performance in an expanded exploratory model, emphasizing etiologic heterogeneity. In a 24-h landmark analysis, the addition of SBP variability improved discrimination for deterioration after 24 h, but these post-admission metrics were not included in the admission-only model. The nomogram provided an internally validated prognostic estimate for enhanced monitoring and reassessment; external validation was required before treatment selection or bedside implementation.