Medicine & Research

Depression is a common symptom associated with multiple sclerosis. Estimates of the prevalence of depression range from 40-60 percent in people with MS. By comparison, approximately 20 percent of the general population experiences depression. Because depression is one key critical determinant of quality of life, and may well be the key determining factor, it should be screened for and treated in people with MS. Depression can also contribute to other problems, including fatigue, cognitive dysfunction, sexual problems, pain, and motor issues. 
 
The effect of brain lesions
 
It was speculated that MS-related lesions in the CNS may contribute to the increased prevalence of depression in patients with MS. Data suggest that the specific location of the lesions may also be a contributing factor. One recent study reported MS patients suffering from depression had “more hyper-intense lesions in the left inferior medial frontal regions and greater atrophy of left anterior temporal regions.” According to Dr. Ben Thrower, medical director of the Andrew C. Carlos MS Institute at Shepherd Center in Atlanta, much still needs to be learned about the relationship between brain lesions and occurrence of depression. Dr. Thrower said, “There is a clear and present need for further research on this topic. Recent advances in the understanding of neuropathology, neuropsychology, and neuroimaging of depression may help to further define the relationship between lesions or lesion load and the occurrence of depression.”
 
The effect of fatigue
 
Fatigue is the most common symptom affecting patients with MS. It has been reported in more than 90 percent of patients with MS. Interestingly, fatigue is a common symptom of both depression and MS.
According to Dr. Thrower, “While fatigue and depression are assumed to be related in people with MS, why or how this relationship exists is not fully understood.”
 
Studies suggest that treating depression in people with MS does seem to produce improvements in fatigue and vice versa. In many cases, it can also be possible to treat fatigue and depression simultaneously.
Generally, antidepressants that are “uplifting” or give energy are preferred. Medications like bupropion (Wellbutrin®), fluoxetine (Prozac®), and venlafaxine (Effexor®) are examples of some “uplifting” antidepressants that may help also decrease the symptoms of fatigue.
 
The effect of disease-modifying therapies
 
Disease-modifying therapies have revolutionized the treatment of MS. These products decrease relapses and accumulation of disease-related damage. In theory, consistent treatment with DMTs can also decrease the symptomatic problems associated with MS, including depression. A lack of consistency, or adherence, can happen for many reasons. Unfortunately, people with MS suffering from depression are less likely to be adherent in taking their DMTs. According to Dr. Thrower, this is something that he commonly sees in clinical practice. It’s thought that this inconsistency can lead to increased symptoms of depression. For this reason, Dr. Thrower suggests that patients have an open dialogue with their treating clinicians regarding adherence with DMTs and the effects of depression on adherence. This should not be a one-way conversation. According to Dr. Thrower, clinicians should also be initiating this discussion with patients.
 
In the early 2000s, when injectable beta-interferon DMTs were approved by the FDA their use was linked with depression and increased rates of suicide. The initial concern arose from clinical trial data where four patients attempted suicide. With the high prevalence rates of depression in patients with MS, many clinicians felt that it was difficult to draw meaningful conclusions from this data. Historically speaking, clinicians have limited the use of these beta-interferon DMTs in those who are experiencing major depressive disorders. More recent studies have found little evidence suggesting a causal link between the beta-interferon DMTs and depression.
 
It is important to note that the beta- interferon DMTs are not the only DMTs that have been associated with depression. Mitoxantrone (Novantrone®) , which is rarely used as a treatment of MS, natalizumab (Tysabri®), and daclizumab (Zinbryta®) have also been linked with depression.
 
The effect of antidepressants
 
There are a plethora of antidepressant medications approved for use in the U.S. As with all medications, adherence and open communication are keys to success. These products simply are not effective if you do not take them. The positive effects are not always immediate – it can take up to two months for the benefits to be attained. Because all medications have side effects, you are again encouraged to have open dialogue with your prescribing clinicians. It is important to understand that finding the “best anti-depressant” may be a trial and error approach.
 
With its high prevalence and high treat-ability, depression is a symptom for which all people with MS should be screened. If you have experienced changes in your mood that might be depression talk to your healthcare team. There is help for MS-related depression.
 
Identifying Depression
 
Depression is a mood disorder characterized by the presence of five or more of the following symptoms for at least two weeks:
 

• A sad mood for most of the day or most days
• A loss of pleasure or interest in one’s usual activities
• Sleeping problems
• Fatigue
• Changes in thinking and motion – either a slowing down of thought and reduced motion, or racing thoughts and restless motion. Changes in weight – either reduced appetite with weight loss or increased
• appetite with weight gain
• Negative self-image
• Feelings of guilt and self-blame
• Reduced concentration and
• Suicidal thinking.

 
If you are having an emotional crisis or experiencing suicidal thoughts, call the National Suicide Prevention Lifeline at 800-273-TALK (800-273-8255).