[Periodic catatonia in schizophrenia spectrum disorders]

Typological differentiation of periodic catatonia in schizophrenia and schizophrenia spectrum disorders (SSD), in particular, schizoaffective disorder.

Seventy-four patients with the verified diagnosis of schizophrenia and SSD (ICD-10 items F20, F21) were studied. The clinical, psychometric (BFCRS, SANS) and statistical methods were used. Clinical and psychometric study of seizures of periodic catatonia was carried out at the following stages: 1) manifestation of a seizure; 2) the maximum severity of psychopathological disorders. Also, at the end of the seizure, an additional assessment of the severity of negative symptoms was carried out using the SANS.

Three forms of periodic catatonia have been identified: hypokinetic, parakinetic, multikinetic. Clinical distinguishing indicators of periodic catatonia seizurs have been established (protracted - two-stage - form of seizures; the phenomenon of «secondary catatonia»). The psychometric study revealed significant differences between the variants of periodic catatonia seizures in terms of the severity of motor phenomena (at both stages of the seizure) and negative disorders. BFCRS scores at the first stage of seizures were as follows: hypokinetic - 9.7±0.4; parakinetic - 12.8±0.9; multikinetic - 32.3±1.6 (the differences were found between 1 and 2 (p<0.05); between 1 and 3, as well as 2 and 3 (p<0.01)). BFCRS scores at the second stage of seizures were 12.1±0.8; 19.9±1.2 and 47.7±1.9, respectively,with the differences between 1 and 2 (p<0.05); between 1 and 3, and also 2 and 3 (p<0.01). The scores on the SANS anhedonia-asociality subscale were 1.9±0.2 for hypokinetic; 2.3±0.3 for parakinetic and 3.2±0.2 for multikinetic with the differences between 1 and 2, 1 and 3, 2 and 3 (p<0.01).

Periodic catatonia is the clinical entity that includes a complex of progressively worsening seizures, the psychopathological systematics of which takes into account the clinical structure of motor disorders, their affiliations with positive and negative dimensions, and functional activity.