BDNF and stroke disorder: The study by Mojatabavi et al., which included 62 case–control studies (as of August 2021) and examined the relationship between altered BDNF concentrations and stroke, indicated that stroke patients had lower serum BDNF levels than healthy controls (SMD = −1.02, 95% CI: −1.47 to −0.57, p-value < 0.001, I2 = 96%, p-value < 0.001), even excluding influential studies (SMD = −0.92, 95% CI: −1.35 to −0.50, p-value < 0.001, I2 = 96%, p-value < 0.001).