Diagnosis of insomnia disorders in chronic mercury intoxication

Abstract

Introduction. It is now known that insomnia has a high comorbidity with various somatic and neurological diseases. In patients with chronic mercury intoxication, sleep disturbances are significantly more common than in the general population. The purpose of the study is to identify the most significant diagnostic criteria for insomnia disorders in patients with occupational chronic mercury intoxication. Materials and methods. The study involved thirty patients with occupational chronic mercury intoxication (CMI), who worked at Usolekhimprom LLC, whose mean age was 56±0.71 years, and 30 patients in the comparison group, whose mean age was 54±0.66 years, who complained of disorders sleep without contact with toxic production factors. A neurophysiological (polysnography), psychological (anxiety and depression level) study was carried out, as well as a quantitative determination of some neurotransmitters in the blood. Results. Polygraphic registration of biopotentials in CMI patients revealed an increase in the time to fall asleep (35.0 (30.5-47.0) min; a decrease in the duration of sleep (total sleep time, 339.5 (305.0-374.0) min); increase in the number of activations (2.9 (1.9-3.6)% of RVO) and total wakefulness during sleep (18.7 (11.3-23.5)%); decrease in the number of sleep cycles (3.0 (2.0-4.0)); decreased sleep efficiency index (70.95 (60.7-78.2)%) and integrative sleep quality index - IISQ (17.8 (13.4-27 ,5)), in the control group, an increase in total wakefulness within sleep (12.2 (8.4-18.6)%); an increase in the latent period of the REM stage (93.0 (72.0-117.0) min); decrease in the number of sleep cycles (3.0 (3.0-4.0)); decrease in the sleep efficiency index (78.4 (73.9-81.5)%) and the integrative sleep quality index - IISQ ( 14.1 (10.9-20.6)). dopamine levels in the blood, compared with the control group. Limitations of the obtained results. The results cannot be generalized to workers as the group included only men. Conclusion. A certain set of diagnostic criteria can be used for the differential diagnosis of insomnia in occupational CMI.