Evidence-Based Psychiatry: Paraclinical Diagnostics of Asthenic Syndrome in Schizophrenia Based on the Determination of Leukocyte-Inhibitory Index

Abstract

A leukocyte-inhibitory index (LII) is the ratio of the proteolytic enzyme leukocyte elastase (LE) to its inhibitor, an α1- proteinase inhibitor (α1-PI). LII characterizes the activity of the proteolytic system and can be considered as a potential objective criterion that determines both the course and the outcome of the disease. The changes of LII in schizophrenia patients with clinically diagnosed asthenia (schizoasthenia) and patients with schizophrenia without clinical signs of this syndrome were revealed. The objective: to study the possibility of the 95% confidence intervals for a comparative assessment of LII in patients with schizoasthenia and patients with schizophrenia without clinical signs of asthenic syndrome to obtain correct statistical conclusions. Patients and methods: Overall, 95 patients aged 20–55 years with paroxysmal-progressive (F20.x1) and paranoid (F20.00) schizophrenia were examined: 61 patients in the total sample were clinically diagnosed with asthenic symptom-complex. The enzymatic activity of LE and the functional activity of α1-PI were determined in blood serum. LII was calculated according to the formula. The confidence intervals were built using 4 different methods: Fieller’s theorem, delta method, regression methods and bootstrap method. Results: the statistical analysis indicates that the 95% confidence intervals of these indicators for the examined patient groups do not overlap. Therefore, these indicators relate to different populations, which mean the examined groups are characterized by different variants of the ratio of the proteolytic system components. Conclusion: the assessment of LII can serve as an objective statistically correct criterion for presence or absence of asthenic disorder in patients with schizophrenia in addition to clinical examination.

Features of Inflammatory Response in Juvenile Depression with Attenuated Symptoms of Schizophrenic Spectrum

“…В качестве ингибитора деструктивного протеолитического потенциала ЛЭ выступает острофазный белок 1 -ПИ [21]. Показано, что соотношение протеаз и их ингибиторов -лейкоцитарно-ингибиторный индекс -в значительной мере определяет течение и исход воспалительной реакции [22,23]. Повышение уровня антител к нейроантигенам рассматривается в качестве фактора, свидетельствующего о более тяжелом патологическом процессе в мозге, ассоциированном с деструктивными изменениями [24].…”