Consortium PSYCHIATRICUMConsortium PSYCHIATRICUMConsortium PSYCHIATRICUM2712-76722713-2919Eco-Vector1106710.17816/CP11067RESEARCHИССЛЕДОВАНИЕResearch ArticleSerum Interleukin-6 in Schizophrenia: Associations with Clinical and Sociodemographic CharacteristicsИнтерлейкин-6 сыворотки при шизофрении: ассоциация с клиническими и социодемографическими характеристикамиhttps://orcid.org/0000-0001-6155-1007ZhilyaevaTatyana V.ЖиляеваТатьяна Владимировна
Russian Federation

MD, Dr. Sci. (Med.), Associate Professor, Psychiatrist, Mental Health Center of the University Clinic; Leading Researcher, Translational Psychiatry Department

д.м.н., доцент, врач-психиатр, Центр психического здоровья университетской клиники; ведущий научный сотрудник отдела трансляционной психиатрии

bizet@inbox.ruhttps://orcid.org/0000-0002-5282-2036RukavishnikovGrigory V.РукавишниковГригорий Викторович
Russian Federation

Leading Researcher, Head of the Social Neuropsychiatry Department

ведущий научный сотрудник, руководитель отдела социальной нейропсихиатрии

bizet@inbox.ruManakovaElvira A.МанаковаЭльвира Александровна
Russian Federation

Director of Medicine

директор по медицине

bizet@inbox.ruhttps://orcid.org/0000-0001-7910-9129MazoGalina E.МазоГалина Элевна
Russian Federation

MD, Dr. Sci. (Med.), Deputy Director for Innovative Scientific Development, Head of the Institute of Translational Psychiatry

д.м.н., зам. директора по инновационному и научному развитию, руководитель Института трансляционной психиатрии

bizet@inbox.ruPrivolzhsky Research Medical UniversityФГБОУ ВО «Приволжский исследовательский медицинский университет» Минздрава РоссииV.M. Bekhterev National Medical Research Centre for Psychiatry and NeurologyФГБУ «Национальный медицинский исследовательский центр психиатрии и неврологии им. В.М. Бехтерева» Минздрава РоссииAVK-Med Centralized LaboratoryООО «Централизованная лаборатория "АВК-Мед"»2811202322122023445161806202312092023Copyright ©; 2023, Zhilyaeva T.V., Rukavishnikov G.V., Manakova E.A., Mazo G.E.Copyright ©; 2023, Жиляева Т.В., Рукавишников Г.В., Манакова Э.А., Мазо Г.Э.2023Zhilyaeva T.V., Rukavishnikov G.V., Manakova E.A., Mazo G.E.Жиляева Т.В., Рукавишников Г.В., Манакова Э.А., Мазо Г.Э.https://creativecommons.org/licenses/by-nc-nd/4.0https://consortium-psy.com/jour/article/view/11067

BACKGROUND: Recently a significant part of schizophrenia studies have been focused on the role of cytokines, especially interleukin-6 (IL-6). Some authors have suggested a pathogenetic role for IL-6 in schizophrenia and concluded that therapy that centers on suppressing IL-6 activity may prove beneficial for certain categories of patients with the disorder. However, many questions about whether the changes in IL-6 levels in schizophrenia are primary, related to symptoms or caused by therapy, are concomitant metabolic disorders, are related to smoking or other secondary factors remain unanswered.

AIM: To assess the level of serum IL-6 in patients with schizophrenia in comparison with healthy controls, as well as to study its association with clinical and socio-demographic characteristics.

METHODS: Some 125 patients with schizophrenia and 95 healthy volunteers were examined. The evaluation of IL-6 was performed by enzyme immunoassay. All patients were assessed using standardized psychometric instruments. Information from patient medical records on the course of the disease and treatment was analyzed.

RESULTS: The level of IL-6 was significantly higher in the patients than in the healthy volunteers (z=2.58; p=0.0099), but among men the difference between the patients and volunteers was not significant. Statistically significant correlations were found between the level of serum IL-6 and the severity of the cognitive impairment of patients: (auditory [ρ=–0.31; p=0.00063] and working memory [ρ=−0.25; p=0.0065], hand-eye coordination [ρ=−0.29; p=0.0011], verbal fluency [ρ=−0.28; p=0.0019] and problem-solving capacity [ρ=−0.22; p=0.013]), total severity of schizophrenia symptoms (PANSS, ρ=0.22; p=0.016), PANSS positive subscale (ρ=0.18; p=0.048), and the age of manifestation (ρ=0.20; p=0.025) and disease duration (ρ=0.18; p=0.043). The level of IL-6 was the lowest in patients treated with third-generation antipsychotics, and the highest in those treated with first-generation antipsychotics (H=6.36; p=0.042). Moreover, in hospital patients, the level of IL-6 was significantly higher than in outpatients and inpatients hospitals (H=18.59; p=0.0001).

CONCLUSION: The study confirmed that there are associations between the serum IL-6 level and schizophrenia, the age of the patient, duration of the disease and how late in one's life cycle it began manifesting itself, as well as a number of clinical characteristics. Considering that IL-6 is associated with a wide range of symptoms that are loosely controlled by antipsychotics, this biochemical marker needs to be studied to look into how closely its level tracks with an unfavorable course of schizophrenia. That would require further prospective studies.

ВВЕДЕНИЕ: В настоящее время при изучении шизофрении большое внимание уделяется роли различных цитокинов, при этом наиболее часто упоминаются изменения уровня интерлейкина-6 (IL-6). Некоторые авторы выдвигали предположения о патогенетической роли IL-6 при шизофрении и целесообразности терапии, направленной на подавление активности IL-6, у определенных категорий пациентов с этим расстройством. Однако до сих пор остается много вопросов о том, являются ли изменения уровня IL-6 при шизофрении первичными, связанными с симптомами, или вызваны терапией, сопутствующими метаболическими нарушениями, курением и другими вторичными факторами.

ЦЕЛЬ: Оценить уровень сывороточного IL-6 у больных шизофренией по сравнению со здоровым контролем, а также изучить его связь с клиническими и социально-демографическими характеристиками.

МЕТОДЫ: Обследовано 125 пациентов с шизофренией и 95 здоровых добровольцев. Оценку IL-6 проводили иммуноферментным анализом. Все пациенты были обследованы с использованием стандартизированных психометрических инструментов. Проанализированы данные медицинских карт о течении заболевания и лечении.

РЕЗУЛЬТАТЫ: Уровень IL-6 был статистически значимо выше у пациентов, чем у здоровых добровольцев (z=2,58; p=0,0099), однако среди мужчин разница между пациентами и добровольцами была незначительна. Выявлены статистически значимые корреляции между уровнем сывороточного IL-6 и выраженностью когнитивных нарушений у пациентов: (слуховой [ρ=−0,31; p=0,00063] и рабочей памяти [ρ=−0,25; p=0,0065], зрительно-моторной координации [ρ=−0,29; p=0,0011], беглости речи [ρ=−0,28; p=0,0019] и проблемно-решающего поведения [ρ=−0,22; p=0,013]), общей тяжестью симптомов шизофрении (PANSS, ρ=0,22; p=0,016), подшкалой продуктивных синдромов PANSS (ρ=0,18; p=0,048), возрастом манифестации (ρ=0,20; p=0,025) и длительности заболевания (ρ=0,18; p=0,043). Уровень IL-6 был самым низким у пациентов, получавших антипсихотики 3 поколения, и самым высоким у получавших антипсихотики 1 поколения (Н=6,36; р=0,042). При этом у пациентов круглосуточного стационара уровень IL-6 был статистически значимо выше, чем у амбулаторных и пациентов дневного стационара (H=18,59; p=0,0001).

ЗАКЛЮЧЕНИЕ: Исследование подтвердило ассоциацию уровня IL-6 сыворотки крови с шизофренией, возрастом больных, длительностью заболевания и его более поздним началом, а также рядом клинических характеристик. Учитывая, что IL-6 связан с широким спектром симптомов, плохо контролирующихся антипсихотиками, данный биохимический маркер нуждается в изучении на предмет ассоциации с неблагоприятным течением шизофрении, что требует дальнейших проспективных исследований.

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