14 DAY TRIAL // In a new study of multiple sclerosis and depression, researchers at the Cedars Sinai Medical Center in New York have established that the two conditions are not necessarily linked. This research supports past investigations demonstrating different pathways for the two condition.
One of the most interesting conclusions in this study was that female patients who were diagnosed with both multiple sclerosis (MS) and a sleuth of depressive symptoms exhibited reduced volume in a brain structure called hippocampus, which plays a role in mood regulation and memory formation.
The team has also found that the left portion of the hippocampus was unaffected by this reduction. Only the right side appeared to lose neurons, an effect that was not recorded in the cases of patients suffering from vegetative depression or other forms of depression (without any accompanying illnesses).
In the new paper, which appears in the latest issue of the medical journal Human Brain Mapping, the team explains that other types of depression did not lead to hippocampal mass reduction even if they caused extreme fatigue in subjects.
“Patients with medical disorders – and especially those with inflammatory diseases such as MS – often suffer from depression, which can cause fatigue. But not all fatigue is caused by depression,” explains Nancy Sicotte, MD, who is a neurologist and MS expert at the CSMC, and also the leader of the study.
“We believe that while fatigue and depression often co-occur in patients with MS, they may be brought about by different biological mechanisms,” adds the expert, who is also the Sicotte, director of the Multiple Sclerosis Program at Cedars Sinai.
The team Sicotte leads is focused on understanding precisely how depression that accompanies multiple sclerosis differs from other forms of depression. This could lead to the development of new diagnostic imaging systems, as well as better, more personalized treatment schemes for patients.
Multiple sclerosis is a relatively unique condition, in that it is responsible for causing a significant array of mental, physical and psychiatric symptoms. The disease works by attacking the myelin sheath covering neurons – a protective layer that insulates the nerve cells and allows them to promptly relay electrical signals.
Without the sheath, it becomes extremely difficult for various areas of the brain to communicate to each other. Some scientists believe that a series of as-of-yet-hidden interplay may be causing a special type of depression, PsychCentral reports.