Can irisin become a biomarker of physical activity, or another metabolic risk assessment parameter, in psychiatric care patients?

Introduction
Physical activity (PA) is considered to be a major preventive factor in psychopharmacotherapy-induced metabolic adverse effects, such as metabolic syndrome induction. The recent discovery of irisin might bring a potential tool with which to supervise patient compliance or create an additional metabolic risk assessment parameter

Material and methods
The sample consisted of 66 in- and out-patients of a Polish hospital. Irisin serum concentrations were measured using commercially available ELISA kits. Sociodemographic and clinical data were obtained from medical records. PA sufficiency was assessed with the use of the International Physical Activity Questionnaire. t-Student, c2 , Fisher’s exact test, Pearson correlation and ANCOVA were used for statistical analysis. The significance level was set at α = 0.05.

Results
The difference in irisin concentrations between patients with sufficient and insufficient PA was not statistically significant. Patients given second generation antipsychotic drugs exhibited lower PA and irisin concentrations than patients on antidepressant drugs or first-generation antipsychotic drugs. Additionally, irisin concentrations were lower in patients with central obesity compared to patients without it.

Conclusions
Irisin does not appear to be a valid, objective tool for the evaluation of patients. However, significant associations between irisin concentrations, psychopharmacotherapy and metabolic parameters were found.