Medical and Biological Sciences XXVI/2 - Collegium Medicum ...

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Julia Feit et. al.
Badanie przeprowadzono dwukrotnie: przed podaniem oraz
około 1,5 godziny po podaniu leczniczej dawki metadonu.
Wykonano Test Łączenia Punktów Reitana A. Arkusz
testowy umieszczano na tablecie graficznym. W obu
częściach testu zmierzono czas wykonania.
W y n i k i . Stwierdzono, że średni czas wykonania
testu TMT A przed podaniem metadonu u osób HIV(-) jest
istotnie statycznie mniejszy niż u osób HIV(+). Natomiast po
podaniu metadonu szybkość psychomotoryczna mierzona za
pomocą Testu Łączenia Punktów TMT A nie jest istotna
statystycznie u osób HIV(-) leczonych w programie
substytucyjnym w porównaniu z osobami HIV(+). Osoby
z grupy HIV (+) istotnie statystycznie szybciej wykonują test
TMTA po podaniu pojedynczej dawki metadonu.
Wnioski. Przyjęcie leczniczej dawki metadonu
przez osoby zakażone wirusem HIV może mieć wpływ na
zwiększenie sprawności psychomotorycznej. Wchodzenie
leków antyretrowirusowych w interakcje farmakokinetyczne
z metadonem może prowadzić do zmiany stężeń metadonu
w ustroju i tym samym powodować zmiany w regulacji
czynności psychomotorycznych.
Key words: opiates, methadone, TMT A, HIV
Słowa kluczowe: opioidy, metadon, TMT A, HIV
INTRODUCTION
Addiction to opioids is one of the strongest forms
of addiction [1, 2]. Using opioids is connected with
adaptive changes in the nervous system [3, 4]. Opioids
affect cerebral neurotransmitters which transmit
information among nerve cells. [5] Psychoactive
substances can cause a release of a bigger or smaller
amount of neurotransmitters into the synaptic cleft or
inhibit the return transport or block its action [6]. Most
of the dysfunctions and deregulations associated with
the intake of opioids affect the brain reward system,
which is probably responsible for the homeostasis of
behavior [7]. It was proven that addiction is linked to
disturbances not only in the reward system, but also in
other major functional systems of the brain [8]. In
particular, it relates to the system associated with the
regulation of cognitive and emotional functions [8].
Structural and functional changes in these structures
are associated with the development of dependence to
psychoactive compounds [8]. Morphological and
functional changes in the striatum, especially in the
ventral striatum (and its main structure - nucleus
accumbens), have been found in addicted individuals.
It is the central structure of the limbic system and the
reward system. According to the current knowledge, a
cortico-subcortical loop is important in the processing
of sensory (visual and auditory perception), cognitive
(attention, executive functions, visual and auditory
memory, spatial memory), emotional (mood) and
motor stimuli (extraocular movements, other skeletal
muscle movements, such as upper limb muscles) [9,
10, 11].
Methadone is a synthetic opioid used in the
substitution therapy of opioid addicts. Substitution
treatment is the most effective method of treatment in
this type of addiction. It lowers the risk of transmitting
viruses: human immunodeficiency virus, hepatitis C
virus, hepatitis B virus (HIV, HCV, HBV) and other
infectious agents causing blood-borne diseases, thus
reducing the mortality rate among drug addicts [12].
Substitution therapy is the administration of a
substitute agent [15]. Blockage of opioid receptors
prevents mental and somatic symptoms of withdrawal
state. The purpose of the therapy is delivering a
controlled dose of a substitute agent, which will enable
normal functioning, rebuilding, preserving health and
reducing or eliminating criminal behaviours [16].
Alterations of the functioning of cortico-subcortical
loops occur in patients infected with HIV which is a
neurotropic virus. Features of subcortical stupor are
found [17]. As a result of the activity of HIV most
likely a damage of the striatum takes place.
Psychomotor (oculomotor, upper limb movements)
disturbances are the expected effect of the HIV virus.
Additionally, emotional (which can be measured by
changes in the functioning of the autonomic nervous
system) and cognitive (disturbances in processing of
information from the external and internal
environment) impairments are seen [10, 11].
In order to assess the impact of a therapeutic dose
of methadone on psychomotor performance of HIV(+)
subjects and HIV(-) subjects treated with the
substitution therapy, a graphomotor test was used. The
time of test completion was measured in subjects from
both groups.
MATERIAL AND METHODS
The study was conducted in the group of 73
participants of substitution program addicted to opioids
and included 32 HIV(-) and 41 HIV(+) subjects.
Twenty eight women and 45 men, participating in
methadone substitution program for an average of 53