Specific metabolic and inflammatory profiles of patients with hyperglycemia in bipolar affective disorder, recurrent depression and schizophrenia: results of a transdiagnostic study

Background. High comorbidity of mental disorders and metabolic syndrome (MS) is the main reason for the reduc-tion in life expectancy of psychiatric patients. The search for biomarkers of MS risk is relevant, and hyperglycemia (HG) as a component of MS is a key target for a comparative study of patients with different diagnoses. Objective. To assess the association of HG with MS components, hematological indices of inflammation, and clinical characteristics of pa-tients with bipolar disorder (BD), recurrent depressive disorder (RDD), and schizophrenia (SZ) within the framework of a transdiagnostic approach. Materials and Methods. The study included 153 inpatients, including 84 women (54.9%) and 69 men (45.1%), with bipolar disorder (n=50), RDD (n=38), and SZ (n=65). Socio-demographic, anthropometric, clinical and laboratory data were obtained from medical records. Results. The diagnostic groups did not differ in age, gender, frequency of somatic diseases and individual components of metabolic syndrome and their combinations. In the RDD group, there was a statistically significant (p=0.0447) increased absolute number of lymphocytes compared with the SZ group and a statistically significant (p=0.044) higher inflammation coefficient LHR (lymphocyte to HDL ratio) compared with the BD group. Comparison of subgroups identified by the presence or absence of HG within the diagnos-tic groups of patients revealed two levels of differences. Patients with HG in all groups had: 1) statistically significantly higher insulin levels: BD (p=0.003), SZ (p=0.013), RDD (p=0.048); 2) statistically significant higher levels of glycated hemoglobin: RDD (p=0.001), SZ (p=0.001), BD (p=0.028). Unique profiles of differences were established in patients with HG: 1) BD: statistically significant higher levels of prolactin (p=0.024) and creatinine (p=0.0069), but lower levels of lymphocytes (p=0.028) and C-reactive protein (p=0.036), older age (p=0.035), later onset of the disease (p=0.023) and first visit to the doctor (p=0.039); 2) RDD: statistically significant higher hemoglobin levels (p=0.02), lower T4 levels (p=0.045), as well as higher BMI (p=0.017) and waist circumference (p=0.041); 3) SZ: no other differences were found except for those common to all groups. Conclusion. The study has shown for the first time that hyperglycemia in pa-tients with bipolar disorder, RDD, and SZ is associated with diagnosis-specific metabolic and inflammatory profiles. The findings confirm the complex bidirectional relationship between mental disorders and metabolic disturbances, emphasiz-ing that metabolic dysregulation is not just a comorbid condition, but an integral part of the disease course, which re-quires close attention from clinicians. Detection of hyperglycemia at the initial consultation is an economically justified and clinically important procedure that allows the psychiatrist to make more informed decisions regarding therapy and metabolic interventions, which improves the quality of life and life expectancy of patients.