Influenza and coronaviruses linked to mood disorders
MedWire News: Patients with mood disorders are more likely to show evidence of infection with influenza A or coronaviruses than mentally healthy individuals, US researchers have found.
Teodor Postolache (University of Maryland School of Medicine, Baltimore) and team also found that seropositivity for influenza B is significantly associated with a history of suicide attempts and psychotic symptoms in mood disorder patients.
Writing in the Journal of Affective Disorders, the researchers explain: "Anecdotal reports of mood disorder following infection with common respiratory viruses with neurotropic potential have been in existence since the last century.
"Nevertheless, systematic studies on the association between these viruses and mood disorders are lacking."
To address this, the team studied 218 patients with unipolar depression or bipolar disorder and 39 mentally healthy controls. Of the participants with mood disorders, 74 reported experiencing psychotic symptoms and 99 had attempted suicide.
Blood samples were collected from all of the participants and assessed for influenza A, B, and coronavirus antibody titers using immunoassays.
After accounting for age and gender, the researchers found that seropositivity for influenza A, B, and coronaviruses was significantly associated with a history of mood disorders, at odds ratios (ORs) of 1.71, 2.65, and 2.72, respectively.
Among individuals with mood disorders, seropositivity for influenza B was significantly associated with a history of suicide attempts, at an OR of 2.53. There was no evidence of an association between seropositivity for influenza A or coronaviruses and a history of suicide attempts.
The team also found that seropositivity for influenza B was significantly associated with a history of psychotic symptoms in mood disorder patients during mood episodes, at an OR of 2.63, but there was no evidence for an association between seropositivity for influenza A or coronaviruses and a history of psychotic symptoms.
Postolache and team conclude: "Our results suggest an association between seropositivity for influenza and coronaviruses, and a history of mood disorders.
In addition, seropositivity for influenza B was associated with suicidal behavior and psychotic features."
They add: "Replicating our results in larger samples with longitudinal follow-ups may have potential public health relevance, especially in the context of the ongoing flu pandemic."
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By Mark Cowen