The paper published by Guillaume Fond and colleagues  concluding that: "Hypovitaminosis D is frequent and associated with depressive symptoms and anxiety disorders in schizophrenia" provides the blogging fodder today. Hypovitaminosis D is just another way of saying vitamin D deficiency (or perhaps insufficiency) and follows a number of previous research findings (see here) concluding that schizophrenia seems to be one of a number of conditions/diagnosis/labels where tested vitamin D levels show sub-optimality.
Fond report results based on their examination of the "national FondaMental Expert Center (FACE-SZ) Cohort", something that has been talked about on this blog before (see here). So: "A comprehensive 2 daylong clinical and neuropsychological battery was administered in 140 SZ subjects included between 2015 and 2017" including vitamin D testing and analyses looking for the signs and symptoms of depression and anxiety.
Results: about one in five of the study participants were in a state of hypovitaminosis D. Looking at the accumulated behavioural data - "Depressive symptoms were assessed by the Positive and Negative Syndrome Scale depressive subscore and current anxiety disorder by the Structured Clinical Interview for Mental Disorders" - I was particularly struck by the *link* between vitamin D deficiency and 'current anxiety disorder' ("aOR = 6.18 [2.15-17.75], p = 0.001"). Further: "Vitamin D supplementation has been administered during the previous 12 months in only 8.5% of the subjects but was associated with lower depressive symptoms... and lower rate of current anxiety disorder... compared to patients with hypovitaminosis D."
These are interesting results. They reiterate that a diagnosis of schizophrenia does not seem to be protective against the development of vitamin D deficiency/insufficiency. They also highlight that schizophrenia perhaps should not be considered as a stand-alone diagnosis; something that is beginning to be realised across various different behavioural labels (see here). The suggestion of an *association* between anxiety and/or depression in the context of vitamin D is also important (perhaps even relevant to other studies that have suggested a direct link between vitamin D and schizophrenia). And then there is the 'already supplemented' finding that seems to fly in the face of quite a lot of other evidence suggesting that correcting vitamin D deficiency in the context of something like depression might not be directly applicable to improvement in depressive symptoms (see here). Research questions remain but the Fond results look interesting...
 Fond G. et al. Hypovitaminosis D is associated with depression and anxiety in schizophrenia: Results from the national FACE-SZ cohort. Psychiatry Res. 2018 Sep 13;270:104-110.