D. R. Bach et al.: Elevated Bilirubin in Acute and Transient Psychotic Disorder. Pharmacopsychiatry 2010; 43: 12–16

Both increased and decreased bilirubin and other antioxidants have been reported in disorders from the schizophrenic spectrum. Vitek et al. [2] have added another piece of evidence towards the latter proposition, which does however not elucidate the reason for these contradictory findings. In our paper that Vitek refers to in his letter, we have furnished a possible explanation [1].

Reports of decreased bilirubin have commonly investigated patients with schizophrenia. However, reports of increased bilirubin encompassed patients with different diagnoses from the schizophrenic spectrum and did not separate patients with schizophrenia from those with, e. g., acute psychotic disorder, schizoaffective disorder, and other, less frequent diseases.

In our sample, only patients with acute and transient psychotic disorder (ATPD, ICD F23) exhibited increased plasma bilirubin. At the same time, the rate of elevated bilirubin (>17 μmol/L) in patients with paranoid schizophrenia (11.3%) was comparable to the incidence of Gilbert's syndrome in the general population (and not “2–4 times higher compared to general population”, as Vitek quotes our finding in his letter) which has been reported as 5–10% [3].

If oxidative stress reflects a pathogenetic process in disorders from the schizophrenic spectrum, one might under normal circumstances expect a reactive elevation of plasma antioxidants to counter this process. It seems perfectly plausible to speculate that a relative lack of antioxidants would be associated with a chronic or recurring, and progressive, disease like schizophrenia, while a normal reactive increase would be associated with a disease that is (by definition) fully remitting, namely ATPD.

References

• 1 Bach DR, Kinder J, Strik WK. Elevated bilirubin in acute and transient psychotic disorder.  Pharmacopsychiatry. 2010;  43 12-16
• 2 Vítek L, Novotná M, Leníček M. et al . Serum bilirubin levels and UGT1A1 promoter variations in patients with schizophrenia.  Psych Res. 2010;  in press
• 3 Bosma PJ. Inherited disorders of bilirubin metabolism.  J Hepatol. 2003;  38 107-117

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