ENO2 and Alzheimer disease: The meta-analysis detected significantly elevated CSF NSE levels in AD (Hedges’ g = 0.822, 95% CI 0.332 to 1.311, p = 0.0010), but the data exhibited very high heterogeneity (Cochran’s Q = 103.74, df = 12, I2 = 88.43%, p < 0.001; Fig. 2).