Reduction of night/day difference in melatonin blood levels as a possible disease-related index in schizophrenia.
OBJECTIVE
Aim of this study was to verify if a simple index as night-day plasma MLT level variation is able to confirm the existing data on circadian melatonin alterations in schizophrenia and if a relationship to disease itself instead of the actual clinical state can be suggested.


METHODS
Ten consecutively admitted male schizophrenic inpatients were examined.


METHODS
The blood samples for melatonin were collected at 3.00 a.m. and 15.00 p.m. and consequently calculated the values of Delta () (MLT h.3.00- MLT h.15.00). We divided the sample into two subgroups: < 30 pg/ml and > 30 pg/ml taking 30 pg/ml as an arbitrary value, based on literature data, that should indicate a physiologically correct value of.


RESULTS
The 70% of the sample was under the 30 pg/ml value of (13.61 +/- 4.0) or was lacking of the characteristic circadian pattern of MLT secretion, whilst the 30% of the sample was over the 30 pg/ml value of (83.60 +/- 16.34) or was in presence of the characteristic circadian pattern of MLT secretion (p=.0001). No correlation was found between values and the scale and subscales scores for the assessment of psychopathology.


RESULTS
The data confirm the lack of the characteristic circadian pattern of MLT secretion in schizophrenics.


CONCLUSIONS
The absence of significant correlation between night / day melatonin level differences and actual psychopathology variables should indicate that the suppression of is mostly related to the disease and independent from the clinical state. A neuroleptic-treatment effect cannot be excluded so far.
Bersani
Giuseppe
G
3rd Psychiatric Clinic, Department of Psychiatric Sciences and Psychological Medicine, University of Rome La Sapienza, Rome, Italy. bersani@uniroma1.it
Mameli
Monica
M
Garavini
Alessandra
A
Pancheri
Paolo
P
Nordio
Maurizio
M
D000328:Adult; D015415:Biomarkers; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D008297:Male; D008550:Melatonin / Q000097:blood*; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000097:blood*; D012565:Schizophrenic Psychology
D015415:Biomarkers; D008550:Melatonin