Vitamin D Supplementation in Chronic Schizophrenia Patients Treated with Clozapine: A Randomized, Double-Blind, Placebo-controlled Clinical Trial

Amir Krivoy*, Roy Onn, Yael Vilner, Eldar Hochman, Shira Weizman, Amir Paz, Shmuel Hess, Roi Sagy, Shiri Kimhi-Nesher, Ehud Kalter, Tal Friedman, Zvi Friedman, Gil Bormant, Sharon Trommer, Avi Valevski, Abraham Weizman

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Background While accumulating evidence suggests that vitamin D deficiency may be involved in the risk to develop schizophrenia and its outcome, there are no studies on vitamin D supplementation in this context. We sought to assess the effect of vitamin D supplementation on psychiatric, cognitive and metabolic parameters in chronic clozapine-treated schizophrenia patients. Methods This eight-week, randomized, double-blind, placebo-controlled clinical trial, recruited schizophrenia patients who had been maintained on clozapine treatment for at least 18 weeks and had low levels of vitamin D (< 75 nmol/l) and total PANSS scores > 70 (to ascertain the presence of residual symptoms). Patients were randomly allocated to either weekly oral drops of vitamin D (14,000 IU) or placebo and subsequently assessed at two-week intervals for psychosis severity, mood, cognition and metabolic profile. Results Twenty four patients were randomly assigned to vitamin D (aged 39.4 ± 9.6 years, 75% males) and the other 23 patients to the placebo arm (aged 42.5 ± 11.2 years, 60.9% males). After eight weeks, the vitamin D group exhibited a significant increase in vitamin D levels (31.4 vs − 0.4 nmol/l, p < 0.0001). There was no significant effect of vitamin D on psychotic, depressive or metabolic parameters. However, in the vitamin D group, there was a trend towards improved cognition (effect size = 0.17, significance lost following Bonferroni correction). Conclusions Vitamin D supplementation was associated with a trend towards improved cognition, but did not affect psychosis, mood or metabolic status. It is possible that the robust decrease in the PANSS scores in both groups may have obscured an effect of vitamin D supplementation.

Original languageEnglish
Pages (from-to)138-145
Number of pages8
JournalEBioMedicine
Volume26
DOIs
StatePublished - Dec 2017

Keywords

  • Clozapine
  • Cognition
  • Metabolic syndrome
  • Mood
  • Schizophrenia
  • Vitamin D

Fingerprint

Dive into the research topics of 'Vitamin D Supplementation in Chronic Schizophrenia Patients Treated with Clozapine: A Randomized, Double-Blind, Placebo-controlled Clinical Trial'. Together they form a unique fingerprint.

Cite this