Zsigeri fájdalom, nocebo-hatások, placebo-analgézia
Authors: Bárdos György 
Published: October 2021

Összefoglaló. A belső szervek működési zavarai gyakran származnak
viselkedési, lelki vagy pszichoszociális okokból, amelyeknek nem mindig vagyunk
tudatában. Minthogy ebben a folyamatban egy bonyolult neuronális hálózat játssza
a fő szerepet, ezeknek a zavaroknak a diagnózisa és terápiája számos tényező
manipulálását igényli.

A funkcionális gyomor-bélhuzam rendellenességek (FGID), például az
irritábilisbél-szindróma (IBS), jellemző példái ennek: olyan működési zavarokról
van szó, amelyek mögött jól detektálható szervi vagy biokémiai elváltozásokat
nem találnak. Ilyenkor szükségesnek tűnik a komplex megközelítés, amely többféle
szakember együttműködését kívánja meg. Szerepe lehet a pszichés vagy életmód
terápiának, a gyógyszeres és fizikai kezelésnek is, és – ahogy ebben a cikkben
megmutatjuk – a placebo-terápiának is.

Summary. Functional disorders of the internal organs frequently are
results of behavioral, mental or psycho-social dysfunctions, although we are
usually not conscious about it. A typical example isirritable bowel syndrome
(IBS), a characteristic functional gastro-intestinal disorder (FGID), which is
regularly accompanied by abdominal pain and irregular intestinal motility and
defecation. It has been shown that this disorder cannot be due to a single
factor, nor is it a result of a local cause. Recently researchers have proven
that malfunction of a complicated neuronal network, including several brain
sites, may be responsible for IBS. It is believed now that IBS is the
consequence of several nocebo-effects.

IBS is a typical source of visceral pain or discomfort, a source that is
frequently difficult to identify. Main factors are stimuli originating from the
gastro-intestinal tract, passing through the spinal cord and reaching several
brain structures, including cortical and sub-cortical sites. It has been shown
that some structures become thicker while others thinner as a result of lasting
visceral pain, resulting in altered top-down effects on the visceral organs.
Several hormones accompany these processes resulting in a complicated network
activity.

Recent research has revealed that IBS requires a complex approach, optimally
provided by a therapeutic team of physicians, psychologist/psychiatrist,
associates, and even the patient himself/herself. They may apply or suggest
medicines, physiotherapy, lifestyle modifications, alimentary changes etc.

An important feature is that the nocebo-effect plays an important role in the
generation of IBS, thus one may think the opposite phenomenon, placebo-effect
could be used in the therapeutic process. And really, placebo-analgesia is a
method frequently used in the therapy of IBS. Placebo-analgesia affects brain
processes, including pain processing, release of hormones, including endogenous
opioids, the primary pain-decreasing factors. A top-down pain-modification
system exists which can be affected and activated by the placebo-analgesia thus
counteracting the nocebo-effects and improving the condition of the
individual.

The placebo phenomenon is interesting in itself, too. By now, the major question
is not the existence of the placebo-effect but the mechanisms behind it.
Recently, as brain-mapping techniques have gained their role in research, a lot
of new information proves that the placebo-effect (as well as the nocebo-effect)
is a complex phenomenon that involves several different brain sites, including
the brain cortex and the limbic system, respectively.P

The placebo-effect is widely used in clinical practice, first of all as a
reference treatment when new drugs or medicines are tested for their
effectivity. There are numerous ethical problems in this area, recently, for
example, when testing Covid-19 vaccines. The main problem is whether it is legal
to keep a non-treated population, whether the placebo-group should be treated
immediately after the trial ends, whether the members of the placebo-group
should get adequate information.