Choroid plexus volume is increased in mood disorders and associates with circulating inflammatory cytokines.

Depressed patients exhibit altered levels of immune-inflammatory markers both in the peripheral blood and in the cerebrospinal fluid (CSF) and inflammatory processes have been widely implicated in the pathophysiology of mood disorders. The Choroid Plexus (ChP), located at the base of each of the four brain ventricles, regulates the exchange of substances between the blood and CSF and several evidence supported a key role for ChP as a neuro-immunological interface between the brain and circulating immune cells. Given the role of ChP as a regulatory gate between periphery, CSF spaces and the brain, we compared ChP volumes in patients with bipolar disorder (BP) or major depressive disorder (MDD) and healthy controls, exploring their association with history of illness and levels of circulating cytokines. Plasma levels of inflammatory markers and MRI scans were acquired for 73 MDD, 79 BD and 72 age- and sex-matched healthy controls (HC). Patients with either BD or MDD had higher ChP volumes than HC. With increasing age, the bilateral ChP volume was larger in patients, an effect driven by the duration of illness; while only minor effects were observed in HC. Right ChP volumes were proportional to higher levels of circulating cytokines in the clinical groups, including IFN-γ, IL-13 and IL-17. Specific effects in the two diagnostic groups were observed when considering the left ChP, with positive association with IL-1ra, IL-13, IL-17, and CCL3 in BD, and negative associations with IL-2, IL-4, IL-1ra, and IFN-γ in MDD. These results suggest that ChP could represent a reliable and easy-to-assess biomarker to evaluate the brain effects of inflammatory status in mood disorders, contributing to personalized diagnosis and tailored treatment strategies.

Prevalence of depression in SARS-CoV-2 infected patients: An umbrella review of meta-analyses.

OBJECTIVE: The COVID-19 pandemic is still spreading worldwide two years after its outbreak. Depression has been reported in around 30% of SARS-CoV-2 infected patients. We aim to synthesize the available meta-analytical evidence in an umbrella review exploring the prevalence of depression during and after SARS-CoV-2 infection. METHODS: First, we performed a narrative umbrella review including only meta-analyses providing a quantitative summary of the prevalence of depression during or after SARS-CoV-2 infection. Then we extracted the prevalence and sample size from the original studies included in each meta-analysis, and after removing duplicate studies, we performed a random-effects model meta-analysis based on single original study estimates. Heterogeneity, publication bias, leave-one-out sensitivity, and subgroup analyses were performed. RESULTS: 14 meta-analyses were included in the umbrella review. The prevalence of depression ranged from 12% to 55% in the presence of high heterogeneity. The meta-analysis based on 85 original studies derived from the included 14 meta-analyses showed a pooled prevalence of depression of 31% (95% CI:25-38%) in the presence of high and significant heterogeneity (Q = 8988; p < 10-6; I2 = 99%) and publication bias (p < 0.001). CONCLUSION: The burden of post-COVID depression substantially exceeds the pre-pandemic prevalence. Health care services for COVID-19 survivors should monitor and treat emergent depression, reducing its potential detrimental long-term effects.