What Causes Depression in MS?
Why are MS patients at such a high risk for depression? The easy answer to this question is that living with MS in and of itself is depressing. Studies show, however, that those with other serious chronic medical conditions do not suffer from the same high rate of depression as do those with MS. By taking a closer look at what causes depression in MS, we can better target and treat its symptoms.
Experiencing a period of depression is not uncommon following the initial diagnosis of MS. Hearing the news that one has a chronic disease, which for now is incurable, has a tremendous impact on both the patient, as well as the family.
Psychologically “catching up” to this new information may take some time. One may initially assume that the prognosis will be the “worst case” scenario, at least until one has time to adjust to his or her unique symptoms and disease course. Prior to developing the skills needed to cope with the diagnosis, one may be susceptible to having depressive episodes, especially if he or she is already prone to depression. Many patients do not realize that most people do eventually adjust and adapt to the diagnosis of MS, but doing so just takes time.
Even after learning to cope with the initial diagnosis, patients will need to continually adjust to altered life circumstances. Some individuals may eventually experience losses which can occur as a result of disease progression. Examples include changes in physical abilities, employment, relationships, and plans for the future. During each of these losses, patients may be vulnerable to depression.
Additionally, recent research shows that depression may be experienced during disease activity. Three predictors strongly correlate to the level of depression the patient experiences. These include:
- Present state of illness (if the individual is currently experiencing an exacerbation)
- Level of uncertainty about new symptoms and the future
- Poor coping skills such as “emotion-centered” and “escape-avoidance” reactions, rather than constructive problem solving
The uncertainty a patient experiences during an exacerbation strongly influences the level of depression that may result. During the course of MS, people can feel as if they have lost control not only of their bodies, but their thoughts and feelings as well. Healthcare providers may be able to reduce the level of depression that patients experience by offering reassurance, answering questions, and working to reduce uncertainty whenever possible.
Focusing on what the patient still has control over can also help to reduce the feelings of depression. Studies show that when individuals have the perception that they can influence their environment, they feel a greater sense of engagement, energy, and happiness.
Damage to the central nervous system caused by physiological changes may impact mood. In some cases, depression is thought to be caused by lesions in the right frontal and temporal lobes of the brain.
The authors of Comprehensive Nursing Care in Multiple Sclerosis (second edition, edited by J. Halper and N.J. Holland, Demos Medical Publishing, 2002) note, “Both clinical depression and less severe emotional distress are common in MS… [occurring at] a rate much higher than in the general population or in other conditions with similar disabilities, e.g., spinal cord injury. In fact, the very high frequency of depression in MS has led many to theorize that it may be due in part to damage to parts of the brain concerned with the regulation of emotions.”
Chemical changes that occur within the body and the brain can affect mood. For instance, studies find that the expression of interferon-gamma (IFN-gamma) and other Th 1-type cytokines (pro-inflammatory protein molecules involved in cell-to-cell communications, shown to worsen MS) correlate with depression scores during an acute exacerbation. Another study showed that the level of depression, as well as IFN-gamma production, declined significantly in MS patients over a 16-week treatment period using cognitive behavioral therapy. These studies suggest that chemical changes caused by MS attacks may in fact cause depression. This would also help to explain why patients are more prone to depression during exacerbations.
Patients report that fatigue is the most disabling of all their MS symptoms. Between 75 and 90 percent of the MS population suffers from fatigue during the course of their illness. When we are exhausted, we are much more likely to feel depressed. We simply do not have the emotional energy to fight depression; we are too tired to do the things we might normally do to ward off depressive symptoms – such as socializing or exercising.
Similar to depression, fatigue impacts every aspect of life. As fatigue robs us of our ability to work, to help others, or to care for our children, we can fall victim to a painful spiral of fatigue causing depression and then depression compounding our fatigue.
You must also take responsibility for pacing yourself and pay attention to what causes your fatigue. Using a journal to rate your fatigue can be a useful exercise. The “Rating Your Fatigue” exercise found on page 145 of this author’s book, MS & Your Feelings: Handling the Ups and Downs of Multiple Sclerosis (Hunter House Inc., 2006), can help give you a structured way to begin monitoring causes of your fatigue.
Medication Side Effects
Some of the medications prescribed to MS patients may be linked to depression. Steroids top the list. These are often prescribed during exacerbations when patients are already vulnerable to depressive symptoms. Steroids tend to induce a short-term euphoric “steroid high” when first given, followed by a plunge into depression once the medication is stopped.
Some neurologists recognize the emotional roller-coaster which steroids can cause and they are prescribing medications to lessen the emotional effects often associated with the treatment. These might include anti-anxiety and antidepressant drugs given prior to starting a steroid treatment.
Many relapsing-remitting MS patients are now taking interferons (Avonex®, Betaseron®, and Rebif®) to help slow the progression of MS and reduce the number of attacks. Anecdotal reports suggest a possible association between this type of immunotherapy and increased depression. Recent follow-up studies, including data from SPECTRIMS and PRISMS trials, failed to show a connection between these drugs and depression.
While this news is encouraging, the interferons have been shown to decrease the amount of serotonin formed in the brain. Decreased levels of this chemical in the brain may be linked to depression. Therefore, individuals who are taking an interferon and experience a change in their emotional state, are advised to talk with their doctor immediately.
Other medications given for MS symptom management may also cause depression. These include: baclofen, prescribed for spasticity; benzodiazepines, taken for dizziness, vertigo, or spasticity; and other sedating drugs. When taking any of these medications, patients, family members, and the treating physician should closely monitor any changes in mood, watching for the signs of depression listed earlier.