What Causes Depression: Newest Research


Research into depression, its causes and its treatment is constant. With about 7% of the population suffering from any of a variety of forms of depression, there is great incentive to determine the causes and develop solutions.

While research is continuous, announcements of findings are occasional. Here are a couple of the more recent announcements.

Shrinking Hippocampus Related to Recurrent MDD

A large study conducted by an international team of researchers, and reported in the June 30th edition of the journal Molecular Psychiatry, concluded that the hippocampi are smaller in those with recurrent major depressive disorder (MDD) than in those who had never experienced depression.

This study, the largest of its kind to date, combined research findings from a number of previous studies. This gave researchers access to the MRI scans of some 9,000 people, which included 1,728 people diagnosed with major depression.

Measurements of nine different brain structures were taken and compared, looking for differences between those with depression and those without. The clear finding was that those who had suffered recurrent MDD had smaller hippocampi (there are two in the brain, one in each hemisphere) than those who had not. The smallest hippocampi were found in those who had first experienced depression before age 21.

What is notable is that brain scans taken during an initial depressive episode showed no difference from those taken from people who had never experienced depression. This points to the idea that hippocampus shrinkage does not occur until more than one episode of depression has occurred.

How this would impact future treatment of depression is far from known, with many more studies to come.

Omega-3 Fatty Acids Benefit Depression with Inflammation

Scientists have announced that one form of omega-3 fatty acids shows benefits to those with depression and body inflammation. Inflammation within the body is part of the body’s immune response. Chronic inflammation is closely related to obesity, cardiovascular disease and cancer, among other diseases. All of these are among the comorbidities to depression.

In a report that appeared in the March 4th edition of the journal Molecular Psychiatry researchers reported on a study of the potential benefits of omega-3 fatty acids in the treatment of depression.

Researchers first took blood tests to look for any of ten markers indicating inflammation within the body. Subjects, all of whom suffered from MDD, were then treated with either one of two forms of omega-3 fatty acid (DHA or EPA) or a placebo.

Those with one or more indicators of inflammation responded with a greater reduction of depressive symptoms when given EPA as opposed to DHA. Those with more than one marker for inflammation had the greatest response.

People with no indicators of inflammation responded less to EPA than to either DHA or the placebo.

If treatments for depression were developed that included EPA, these results would imply a complication, requiring the monitoring of inflammation levels to maximize the efficacy of treatment.

Sources: Brain & Behavior Research Foundation (Hippocampus Research) and Brain & Behavior Research Foundation (Omega-3 Research)

Image courtesy: Wikipedia.org


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