Low vitamin D is associated with negative and depressive symptoms in psychotic disorders.
There are indications that low S-25(OH)D is associated with increased disease severity in psychotic disorder. Our first aim was to investigate the relations between low S-25(OH)D and positive, negative and depressive symptoms. Our second aim was to explore if associations between S-25(OH)D and symptoms were influenced by levels of inflammatory markers.



Participants (N=358) with a medical history of one or more psychotic episodes were recruited. Current symptomatology was assessed by The Structured Interview for the Positive and Negative Syndrome Scaleanalyzed by a five-factor model. The Calgary Depression Scale for Schizophrenia was used to assess depression and suicidal ideation. Blood samples were analyzed for S-25(OH)D, CRP, sTNF-R1, IL-Ra and OPG. We performed bivariate correlations and multiple regression models to evaluate the effect of S-25(OH)D on the outcomes.



Low S-25(OH)D was significantly associated with negative symptoms (adjusted R2=0.113, F(6,357)=8.58, p<0.001) and with depression (adjusted R2=0.045, F(4,357)=5.233, p<0.001) when adjusting for possible confounding factors (i.e. gender, education, diagnose, hospitalization status, ethnicity, season and thyroid status). CRP was correlated with both S-25(OH)D (rho=-0.13, p=0.02) and negative symptoms (rho=0.14, p=0.01), but did not act as a mediator. The correlations between S-25(OH)D and the inflammatory markers sTNF-R1, IL-Ra and OPG were not significant.



There is a strong association between low S-25(OH)D and higher negative and depressive symptoms in psychotic disorders. Randomized controlled trials should be performed to investigate the effect of vitamin D supplementation as adjuvant treatment strategy in patients with prominent negative or depressive symptoms.
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: mari.nerhus@medisin.uio.no.
Mari
M
Nerhus
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: a.o.berg@medisin.uio.no.
Akiah O
AO
Berg
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: l.r.kvitland@medisin.uio.no.
Levi R
LR
Kvitland
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: ingrid.dieset@medisin.uio.no.
Ingrid
I
Dieset
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: sigrun.hope@gmail.com.
Sigrun
S
Hope
Hormone Laboratory, Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway. Electronic address: sadahl@ous-hf.no.
Sandra R
SR
Dahl
Regional Center for Clinical Research in Psychosis, Psychiatric Division, Stavanger, Norway. Electronic address: melissa.anne.elin.authen.weibell@sus.no.
Melissa A
MA
Weibell
Regional Centre for Early Intervention in Psychosis, Division of Mental Health and Addiction, Oslo University hospital, Norway. Electronic address: UXROMK@ous-hf.no.
Kristin L
KL
Romm
Section of acute psychiatry, Division of Mental Health and Addiction, Oslo University hospital, Norway. Electronic address: ann.farden@medisin.uio.no.
Ann
A
Faerden
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: o.a.adreassen@medisin.uio.no.
Ole A
OA
Andreassen
NORMENT, K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo and Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway. Electronic address: ingrid.melle@medisin.uio.no.
Ingrid
I
Melle
D000328:Adult; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D003863:Depression / Q000097:blood* / Q000150:complications* / Q000276:immunology; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000097:blood / Q000150:complications* / Q000276:immunology / Q000523:psychology*; D012044:Regression Analysis; D012559:Schizophrenia / Q000097:blood / Q000150:complications / Q000276:immunology; D012565:Schizophrenic Psychology; D059020:Suicidal Ideation; D014808:Vitamin D Deficiency / Q000150:complications* / Q000276:immunology / Q000523:psychology*
D015415:Biomarkers
Inflammation; Psychosis; S-25(OH)D; Schizophrenia; Symptomatology