Half of people with multiple sclerosis (MS) will develop clinically significant depression over the course of their lifetime, neuropsychiatrist Anthony Feinstein, Ph.D., in his new book Mind, Mood and Memory: The Neurobehavioral Consequences of Multiple Sclerosis.
However, healthcare professionals, MS patients, and their caregivers tend to overlook depression, focusing instead on the patients’ physical disabilities that hinder daily life, according to Feinstein. Depression can negatively impact a processing speed, a key cognitive ability, making it difficult to work and to perform daily tasks, he says.
Managed Healthcare Executive®spoke with Feinstein, professor of psychiatry at the University of Toronto about the significance of depression in MS and how MS patients can receive better treatment for depression.
Let’s talk about the scope of the problem. You write that 50% of people with MS will develop “clinically significant depression” over the course of their lifetime. Is that based on your research?
Numerous studies now that depression is very common [in MS]. It can affect one out of two people with MS and some studies show 25% of people with MS have clinically significant depression. There is a lot of replicated research on this.
The next question is why is it so common. The early theories were, you’ve got a disease like MS that is incurable, it is understandable you are going to be depressed.
To a degree that is true. But we now know that depression may be caused by what is going on in the brain, and that by itself may be causing the depression. The parts of the brain that control mood become affected by the inflammation of MS and lead to depression.
You write that depression can slow down cognitive function and processing speed. What is the significance of that effect?
Cognition is a major problem in MS. These cognitive difficulties start very early in the disease. In relapsing-remitting MS, for example, 40% of patients have [cognitive difficulties]. Large numbers of people with MS will have cognitive dysfunction. Depression may make it worse, but by itself, these are major problems.
When you are cognitively impaired, you can have difficulty maintaining a job, you can struggle with relationships, and you can lose the ability to drive. These things are not routinely being picked up in clinic. That does patients a major disservice. When patients’ rate the most important problems in MS, cognitive function is in the top three, every time.
There is evidence to suggest that, if you have a clinically significant depression, it can slow down the speed with which you process information. MS patients suffer with processing speed, and depression could slow down the processing speed even further.
Do many neurologists and other healthcare providers recognize the brain abnormalities that lead to depression?
Many neurologists don’t pick up on the behavioral changes and the cognitive changes. There is still a lot of education to do in the neurological community. MS is not just a disease of mood, memory, processing speed, and executive functioning — all of the things that are meant to function well in a day-to-day setting. You’ve got to piece it out through testing. A lot of these things can be missed in a busy neurological practice.
Sometimes, very subtle brain abnormalities may escape detection, but someone who is skilled in more specific MRI analysis can detect changes in normal-appearing brain tissue.