Effects of psychosensory stimulation on anal pressures: Effects of alfuzosin

Abstract

Defecatory disorders (DD) result from reduced rectal propulsive forces and/or decreased anal relaxation during defecation. 1,2 Among those with DD, nearly 48% have a psychiatric diagnosis (44% with depression and 17% with anxiety), 30% have irritable bowel syndrome (IBS), and 18% have a history of abuse before the DD is diagnosed. 3 Whether anxiety and depression predispose to or are a consequence of DD is unknown. While mental stress can induce colonic sensorimotor dysfunctions, the effects of mental stress and relaxation on the anal sphincter have not been evaluated. 4,5 AbstractBackground: Our aim is to explain the lack of clarity in the ways in which anxiety and depression, which are common in defecatory disorders (DD), may contribute to the disorder. In this study, we evaluate the effects of mental stress and relaxation on anal pressures and the mechanisms thereof. Methods:In 38 healthy women and 36 DD patients, rectoanal pressures were assessed at rest and during mental stressors (ie, word-color conflict [Stroop] and mental arithmetic tests) and mental relaxation, before and after randomization to placebo or the adrenergic α 1 -antagonist alfuzosin. Key Results:During the baseline Stroop test, the anal pressure increased by 6 ± 13 mm Hg (mean ± SD, P = 0.004) in healthy women and 9 ± 10 mm Hg (P = 0.0001) in constipated women. During mental arithmetic, the anal pressure increased in healthy (4 ± 8 mm Hg, P = 0.002) and constipated women (5 ± 9 mm Hg, P = 0.004). After relaxation, anal pressure declined (P = 0.0004) by 3 ± 4 mm Hg in DD patients but not in controls. Alfuzosin reduced (P = 0.0001) anal resting pressure (by 31 ± 19 mm Hg) vs placebo (16 ± 18 mm Hg). However, during the postdrug Stroop test, anal pressure increased (P = 0.0001) in participants who received alfuzosin but not placebo. Conclusions & Inferences:In healthy controls and DD patients, mental stressors likely increased anal pressure by contracting the internal anal sphincter; relaxation reduced anal pressure in DD patients. Alfuzosin reduced anal resting pressure but did not block the Stroop-mediated contractile response, which suggests that this response is not entirely mediated by adrenergic α 1 receptors.

Rectal Foreign Bodies: Surgical Management and the Impact of Psychiatric Illness

“…The study interpreting this data was doing so in patients with defecatory disorders, 48% of whom had a diagnosed psychiatric illness. The authors could not conclude whether a mental health problem caused the defecatory disorder or whether it was vice versa [11]. In relation to our study and owing to the bidirectional flow of information through the "brain-gut axis," could manual relaxation of the internal anal sphincter through the placement of a foreign body induce a more relaxed state of mind?…”

“…Mental stress has also been shown to increase anal pressures via contraction of the internal anal sphincter through increased sympathetic nervous system activity [11]. Conversely, a relaxed state of mind is associated with reduced anal pressures in constipated patients.…”

Mechanisms, Evaluation, and Management of Chronic Constipation

“…The adrenergic a 1 receptor antagonist alfuzosin, which probably relaxes the internal anal sphincter, reduced anal pressures in healthy people and patients with DD, but did not improve symptoms of DD. 55,157 Sacral nerve stimulation increases pancolonic antegrade propagating sequence frequency in patients with STC. 158 Contrary to findings from uncontrolled studies, 159 findings from more rigorous studies [160][161][162] and from a double-blind study of 45 patients with constipation are less encouraging.…”

A new method for assessing anal distensibility with a barostat and magnetic resonance imaging in healthy and constipated women

“…Anal resting pressure is primarily maintained by the internal and to a lesser extent by the external anal sphincter 9 . Supporting a role for the internal anal sphincter, isosorbide dinitrate, the adrenergic α 1 ‐receptor antagonist alfuzosin, and internal anal sphincterotomy reduced anal resting pressure in patients with anal hypertension 10‐13 . Pudendal nerve blockade reduced anal resting pressure and the electromyography amplitude of the external anal sphincter and puborectalis muscle measured at rest in healthy women and men, which demonstrates the contribution of the external anal sphincter and puborectalis to resting tone 14,15 .…”