Friday, June 23, 2017

Brain Inflammation Linked to OCD, Study Suggests


Brain inflammation appears to be significantly higher in people with obsessive-compulsive disorder (OCD) than those without the condition, according to a study published this week in JAMA Psychiatry

“This finding represents one of the biggest breakthroughs in understanding the biology of OCD, and may lead to novel therapeutic treatments,” senior author Jeffrey H. Meyer, M.D., Ph.D., said in a press release. Meyer is the head of the Neurochemical Imaging Program in Mood and Anxiety at the Centre for Addiction and Mental Health (CAMH) in Toronto. 

A new direction for developing treatments for OCD is welcomed because about one-third of patients with OCD do not adequately respond to current medications, such as antidepressants, according to the authors.

Meyer and colleagues recruited 20 people with OCD and 20 age-matched healthy controls for the study. The participants were all in good physical health, were not taking medications, and were between the ages of 19 and 48. None of the participants had a history of autoimmune disease or neurologic illness or injury. Psychiatric disorders and OCD were confirmed using the Structured Clinical Interview of DSM-IV.

All participants underwent a positron emission tomography (PET) scan, using a fluorine dye to measure a marker of microglial activity in six brain regions (dorsal caudate, orbitofrontal cortex, thalamus, ventral striatum, dorsal putamen, and anterior cingulate cortex). Activated microglia (immune cells) are known to trigger neuroinflammation.

The researchers found that in people with OCD, inflammation was on average 32% higher in these regions than among those without the condition. 

“To our knowledge, this is the first study demonstrating inflammation within the neurocircuitry of OCD,” Meyer and colleagues wrote. “Although pharmaceutical development does not traditionally prioritize OCD, neuromodulatory treatments under development for other diseases associated with microglial activation, such as Alzheimer disease, might be repurposed toward OCD.” 

For related information, see the Psychiatric News article “Report Highlights Alternative Treatment Options for OCD.”

(Image: iStock/JohnnyGreig)