Effects of depression and/or anxiety on the changes of anorectal motility and rectal sensation in patients with diarrhea-predominant irritable bowel syndrome

Objective To study the effects of depression and/or anxiety on the changes of anorectal motility and rectal sensation in patients with diarrhea-predominant irritable bowel syndrome(IBS-D).Methods 58 patients with IBS-D registered to Second Affiliated Hospital of Guangzhou Medical College between January 2008 and June 2009 were evaluated by Hamilton Anxiety Scale(HAMA) and Hamilton depression scale(HAMD).They were randomly divided into two groups according to investigated results(with and without depression and/or anxiety status).Anorectal motility and rectal sensation in these two groups were determined by Medtronic PC-Polygraf HR and compared with results from 25 healthy subjects(HS) as the control group.Results(1)When elevated abdominal pressure,the net increase in pressure of anal sphincter was(3.0±0.9)kPa in the patients with depression and/or anxiety status group and(3.0±1.0)kPa in those without depression and/or anxiety status group,compared with HS[(3.6±1.6)kPa,P0.05].The rectal lowest volume of sensory threshold,maximal volume of tolerance and maximal compliance were respectively(57.2±38.4)mL,(149±50.8)mL,(20.1±12.6)mL/kPa in the patients with depression and/or anxiety status group,(67.3±39.3)mL,(170.6±49.3)mL,(26.3±10.1)mL/kPa in the patients without depression and/or anxiety status group,which were much lower when compared with HS[(80± 38)mL,(190±50)mL,(30.8±15.2)mL/kPa,P0.01 and P0.05].(2)The static rectal pressure,pressure of anal sphincter,maximal squeeze pressure of anal sphincter,net decrease in pressure of anal sphincter at imitated defecation showed no significant statistical differences between the two groups(P0.05).Conclusion(1)Higher sensitivity,lower tolerance,lower compliance of rectum and weakened autonomous anal control in IBS-D may be associated with diarrhea and frequent defecation.(2)There was no association between depression and/or anxiety status and anorectal motility in patients with IBS-D.Further studies in larger patient groups may be needed to confirm the effects of depression and/or anxiety status on rectal sensations in the patients with IBS-D.