Pharmacotherapy of insomnia in patients with occupational chronic mercury intoxication

Abstract

Introduction. Among occupational poisoning, chronic mercury intoxication (CMI) in the Irkutsk region occupies a leading position. Objective. To give a comparative analysis of the methods of pharmacotherapy of sleep disorders in patients in the long-term CRI. Material and methods. The study included 60 patients with long-term CRI, divided into two equal groups of 30 cases: in the first, the average age was 56.0 ± 0.7, in the second, the average age was 57.1 ± 3.0. Questionnaires were conducted using the hospital scale of anxiety and depression, electroencephalographic, polysomnographic studies before and after treatment. During the study, two treatment regimens for sleep disorders were implemented: the first regimen included the administration of an antidepressant (trazodone) and the chemical analog of melatonin (melaxen), and the second regimen was zolpidem. Statistical processing of the research results was carried out using the software package “Statistica 6.0”. Results. After treatment, in the first group there was an increase in the duration of the total sleep time (p = 0.0008), a decrease in the time of falling asleep (p = 0.004), a decrease in the total number of activations (p = 0.00005), and the time of wakefulness in bed (p = 0.0018), an increase in the representation of delta sleep (p = 0.03), and REM sleep (p = 0.004), an increase in the sleep efficiency index (p = 0.0008), and a decrease in the integrative sleep quality index (p = 0.001). In the second group, only a decrease in the latent period of stage 1 (time of falling asleep) was established (p = 0.05). Discussion. After treatment with trazodone in combination with melaxen, a decrease in the severity of presomnic and intrasomnic disorders was found, and in patients taking zolpidem, only the severity of presomnic disorders was reduced. The results confirm the hypothesized cause of dissominal disorders in CRI (changes in the activity of the limbic-reticular complex). Conclusion. The use of trazodone in combination with melaxen proves the improvement of the qualitative and quantitative indices of the structure of night sleep in patients in the long-term postexposure period of CRI.