However, patients with AIS had higher serum ghrelin than healthy controls (WMD = 1.42, 95% CI 0.48 to 2.35, p = 0.003), and the heterogeneity of the included three studies also was statistically significant (p < 0.0001, I2 = 91%) (Fig. 5). Here, GHRL is linked to androgen insensitivity syndrome.