The association between blood enzyme activity in patients with depression and delusional disorders and their response to psychopharmacotherapy

Objective. To identify biochemical parameters correlated with the characteristics of the clinical response to psychopharmacotherapy (PFT) in patients with depressive-delusional states of various nosological origins. Material and methods. This study included 54 patients, aged 18 to 52 years, diagnosed with depression and delusional disorders across various nosological categories (F20.02; F25.1; F31.5 according to ICD-10). Scores were obtained using the Positive and Negative Syndrome Scale (PANSS) and the Hamilton Depression Rating Scale (HAM-D), both administered before and after PPT. Prior to initiating treatment, the activity of enzymes involved in energy metabolism, glutamate metabolism, and antioxidant/glutathione metabolism in platelets and red blood cells was measured. Results. The patient population was segmented into two distinct diagnostic subgroups: schizophrenia spectrum disorders (SSD; F20.02; F25.1; n=34) and affective spectrum disorders (F31.5; n=21). Biochemical parameters were identified within these subgroups that correlated with reductions in PANSS (redPANSS) and HAM-D scores, as well as with scores on these scales following completion of the PPT (PANSS2). In the subgroup with affective disorders, significant correlations were observed between creatine phosphokinase (CPK) activity and redPANSS-Neg (R=0.47, p=0.02), as well as with PANSS-Neg2 (R=–0.52, p=0.01); glutamate dehydrogenase activity also correlated with PANSS-Pos2 (R=–0.48, p=0.01). In the SSD subgroup, correlations were found between CPK and glutathione S-transferase (GST) activity and redPANSS-Pos (R=0.38 and R=0.44, p<0.03). Furthermore, within two distinct patient clusters (n=29 and n=26) identified by biochemical characteristics, notable correlations were observed: in the larger cluster, the CPK activity correlated with redPANSS-Tot, redPANSS-Pos, redPANSS-Neg, and PANSS-Tot2 (R=0.47, R=0.53, R=0.43, R=–0.47, p<0.02); in the smaller cluster, a correlation was identified between the red blood cell GST activity and redPANSS-Neg (R=0.46, p=0.02). Conclusion. The identified significant correlations between biochemical parameters and the degree of reduction in the total score on psychometric scales after the course of therapy make it possible to use these potential candidates as biomarkers in clinical practice to predict the effectiveness of PFT.