Clinical symptoms including nausea, abdominal fullness, abdominal pain, abdominal discomfort and glasgow score in FD patients were significantly higher compared to healthy volunteers. * vs. healthy volunteers, p=0.001. **vs. healthy volunteers, p<0.001 ***vs. healthy volunteers, p=0.01. ****vs. healthy volunteers, p<0.001. *****vs. healthy volunteers, p<0.0001.