Characterization of autonomic dysfunction in patients with irritable bowel syndrome using fingertip blood flow

Abstract

Fingertip blood flow (FTBF) as measured by laser Doppler flowmetry (LDF) measurement is considered an indicator of sympathetic nerve function. We evaluated autonomic function in patients with irritable bowel syndrome (IBS) by assessing FTBF with both LDF and continuous-wave (cw) Doppler sonography. Firstly, the two methods were compared in 40 healthy volunteers. Next, 59 patients with IBS as well as 118 healthy volunteer controls were studied. In the supine position, FTBF in the right index finger was measured with cw Doppler sonography, whereas FTBF in the left index finger was assessed with LDF. After baseline measurement for at least 5 min, the volunteers received sympathetic stimulation from cold stress applied without notification in the form of an icebag (0 degrees C) upon the left forearm for 1 min. The new cw Doppler sonography method can be used in place of the old LDF method for clinical purposes. FTBF velocity before stimulation (V(pre)) was significantly lower in the IBS group than that in the healthy volunteers (P < 0.01). In addition, the time required for FTBF to return to V(pre) after stimulation was significantly longer in the IBS group than that in the control group. (P = 0.02). Thus, measurement of FTBF with cw Doppler sonography can be useful in the assessment of sympathetic nerve function. The IBS patients showed an abnormal FTBF response suggesting the presence of excess sympathetic activity.

Pathophysiology underlying irritable bowel syndrome -From the viewpoint of dysfunction of autonomic nervous system activity-

“…As might be expected, increased sympathetic nervous system activity and decreased parasympathetic nervous system activity were the most frequently noted differences when IBS patients were compared with healthy controls (Table 1). Recently we reported on autonomic nervous system dysfunction in patients with IBS using fingertip blood flow as measured by laser Doppler flowmetry (Tanaka et al, 2007). We found that IBS patients had increased sympathetic nervous system activity, which is consistent with previous studies.…”

“…Tillish et al (2005) reported the same results as Robert et al (2006). Our data (Tanaka et al, 2007) were also consistent with these reports. Data from previous studies has been inconsistent regarding bowel habit effect, with the complicating factors being difficulties in classification and possible multiple physiological pathways for a similar symptom picture.…”

“…Increased sympathetic nervous system activity and decreased parasympathetic nervous system activity are the most frequently noted signs in IBS patients, which leads to the possibility of visceral hypersensitivity in IBS patients. We often observed cutaneous hyperalgia in IBS patients (Tanaka et al, 2007). The present study could not determine exactly whether or not this was a result of impaired extrinsic gut nerve activity, but this finding is supported by several previous studies.…”

Relation between blood flow and tissue blood oxygenation in human fingertip skin

“…In recent years, laser Doppler flowmetry-noninvasive continuous measurement of BF-has been applied extensively to study various tissues including fingertip skin (Khan et al, 1992;Littleford et al, 1999;Abbink et al, 2001;Mayrovitz and Groseclose, 2002;Freccero et al, 2003;O'Brien, 2005;Tanaka et al, 2008;Hayashi et al, 2009). However, simultaneous measurement of BF and StO 2 in a small area of human fingertip skin has not been reported.…”

The role of psychiatric symptoms, alexithymia, and maladaptive defenses in patients with functional dyspepsia

“…[9] The autonomic nervous system as well as stress hormone system and psychoneuroimmunological branches of the brain-gut axis may be mediators of this link. [10][11][12] Psychosomatic research was shown to link the predisposition to functional gastrointestinal illness with specific personality states and the onset of symptom with exposure to stressful life events. [13] Alexithymia is considered to be a personality state of deficiency in understanding, processing, or describing emotions.…”