Low vitamin D levels may contribute to depression in psychotic disorders

Low vitamin D levels were associated with negative and depressive symptoms among individuals with a history of psychotic episodes, according to data presented at the International Early Psychosis Association meeting.

“The prevalence of vitamin D deficiency is higher in persons with psychotic disorders than in the general population. Low levels of S-25(OH)D is found in patients with acute psychotic episodes. Studies also find links between low S-25(OH)D and general negative symptoms and passive apathetic withdrawal while other[s] find associations to higher levels of social anhedonia and poverty of speech only in males,” Mari Nerhus, MD, a PhD student at the Oslo University Hospital in Norway, and colleagues wrote. “The strongest link between low S-25(OH)D and psychiatric symptomatology is found in depression and suicide attempters have significantly lower S-25(OH)D than non-suicidal patients.”

To assess associations between low vitamin D levels and depressive symptoms, researchers evaluated 358 individuals with a history of one or more psychotic episodes. Current symptoms were determined by the Calgary Depression Scale for Schizophrenia and vitamin D levels came from blood samples.

When adjusting for gender, education, diagnosis, hospitalization status, ethnicity, season and thyroid status, low vitamin D levels were significantly associated with negative symptoms (P < .001) and depression (P < .001).

C-reactive protein correlated with vitamin D levels (P = .02) and negative symptoms (P = .01) but was not a mediator.

Researchers did not find significant associations between vitamin D and inflammatory markers soluble tumor necrosis factor receptor 1, interleukin-1 receptor antagonist, and osteoprotegerin.

“There are strong associations between lower S-25(OH)D and higher negative and depressive symptoms in psychotic disorders,” Nerhus and colleagues wrote. “Clinicians are encouraged to measure S-25(OH)D as part of assessments and randomized controlled trials should be performed to investigate the effect of vitamin D supplementation as a possible adjuvant treatment strategy in patients with low S-25(OH)D and a psychotic disorder with prominent negative or depressive symptoms.” – by Amanda Oldt

Reference:

Nerhus M, et al. Vitamin D in psychotic disorder — Associations with symptomatology and cognition. Presented at: International Early Psychosis Association Annual Meeting; Oct. 20-22, 2016; Milan.

Nerhus M, et al. Schizophr Res. 2016;doi:10.1016/j.schres.2016.08.024.

Disclosure: Nerhus and colleagues report no relevant financial disclosures.