Could peripheral immunological markers discriminate schizophrenia and schizoaffective disorders from bipolar disorder?

INTRODUCTION

Schizoaffective disorder (SZ-AFF) is a controversial diagnostic at the interface between bipolar disorder (BD) and schizophrenia (SZ). Immunological profiles should discriminate these disorders notably during an acute phase. The objective of this study is to characterize the immunological profile of SZ-AFF as compared to SZ and BD and to assess wether the manic phase differs between SZ-AFF and BD.

METHODS

White blood cells and ratio were compared across diagnosis SZ-AFF; SZ and BD in this retrospective study. These same markers were also compared in patients during mania between SZ-AFF and BD. Correlations between psychometric scales and these markers were performed.

RESULTS

Neutrophil-lymphocytes ratio was lower in SZ-AFF as compared to SZ (p = .04) and to BD (p = .03). Leukocytes (p = .02), neutrophils (p < .01), monocytes (p = .01) levels were lower in SZ-AFF as compared to BD but not SZ. We found that patients with SZ-AFF had lowest leukocyte (p = .03) and neutrophil (p = .01) levels than patients with BD during mania. We found a negative correlations between PANSS total score and lymphocyte (p = .03) and monocyte (p = .01) levels in SZ-AFF.

CONCLUSION

In our study, we found that the immunological profiles could specifically discriminate patients with SZ-AFF, SZ or BD patients and that the immunological profile of SZ-AFF is closer to SZ than to BD. Further mania may involve different immunological mechanisms according to the diagnosis. Thus, we may consider SZ-AFF as a clinical/immunological spectrum of SZ.