Depression is not just an emotional reaction to the diagnosis of multiple sclerosis: it is a true complication of the disease, linked to the very mechanisms of MS. It affects up to half of the people affected during their lifetime and has a direct and significant impact on cognitive functions. Recognizing depression, understanding its link with cognition, and treating it appropriately are essential steps to preserve one's brain and quality of life.

Depression in MS: more than a reaction to diagnosis

It is natural to feel sad, discouraged or anxious after a diagnosis of multiple sclerosis. However, the depression that affects people with MS often goes beyond a simple psychological reaction to the disease. Biological mechanisms specific to MS contribute directly to depression, explaining its high frequency in this population.

Brain lesions caused by MS can affect regions involved in mood regulation. The chronic inflammation present in the disease also influences neurotransmitters such as serotonin and dopamine, involved in depression. The background treatments for MS, especially interferons, can also have side effects on mood. Depression in MS has multiple causes, both psychological and biological.

Distinguishing depression from fatigue

One of the challenges in MS is to distinguish depression from fatigue, an omnipresent symptom of the disease. Both share common manifestations: lack of energy, difficulty motivating oneself, sleep disturbances, concentration difficulties. Yet, distinguishing them is important because their treatments differ.

MS fatigue is typically physical and mental, worsened by effort and heat, partially relieved by rest. Depression is more characterized by persistent sadness, a loss of pleasure in usually enjoyable activities, a feeling of hopelessness or worthlessness, sometimes dark thoughts. In reality, the two often coexist and worsen each other.

Impact of depression on cognitive functions

Depression has a direct and measurable impact on cognitive functions, independently of the effects of MS itself. In people with MS, this impact adds to the cognitive disorders already caused by the disease, creating a particularly challenging situation. Recognizing and treating depression can therefore have significant positive effects on brain capabilities.

Psychomotor slowing

Depression is typically accompanied by an overall slowing: slowing of thought, speech, movements. This psychomotor slowing resembles the cognitive slowing of MS and adds to it, amplifying difficulties. Depressed people with MS may feel even slower than they actually are due to the disease alone.

Concentration and memory disorders

Depression profoundly affects attention and memory. Negative thoughts and ruminations monopolize attentional resources, leaving little room to focus on other things. Working memory, which allows for maintaining and manipulating information in the short term, is particularly affected. Depressed people often feel like they have memory gaps, even if their long-term memory remains relatively preserved.

• Concentration difficulties: The mind is overwhelmed by negative thoughts that prevent focusing on a task
• Altered working memory: Difficulty retaining and manipulating several pieces of information simultaneously
• Indecision: Even simple decisions become difficult to make
• Negative thinking: Tendency to see everything in black, which biases information processing

Loss of motivation and initiative

Depression is often characterized by a loss of motivation and initiative, what psychiatrists call anergy or abulia. People affected have difficulty starting activities, even those they know are important or enjoyable. This loss of motivation can be mistaken for laziness or a lack of will, whereas it is a real symptom of depressive illness.

This loss of motivation has direct consequences on cognitive training. A depressed person may struggle to motivate themselves to do their daily exercises with EDITH or JOE, even if they know it's good for them. Therefore, treating depression is an important prerequisite to fully benefit from cognitive stimulation.

During my depression, I felt like I had lost 50 IQ points. I could no longer concentrate, retain anything, or make the slightest decision. When I was finally treated, it was like the fog gradually lifted. My cognitive difficulties related to MS were still there, but they were no longer amplified by depression.

Catherine, 46 years old, MS for 11 years

Recognizing the signs of depression

Depression is often underdiagnosed in MS, partly because its symptoms overlap with those of the disease itself. However, recognizing it is essential because it can be effectively treated. Here are the signs that should alert and prompt discussing with your doctor.

Symptoms to monitor

• Depressed mood: Persistent sadness, feelings of emptiness or hopelessness, most of the time, for at least two weeks
• Loss of interest or pleasure: Activities usually enjoyable no longer appeal and provide no satisfaction
• Sleep disturbances: Insomnia or, conversely, hypersomnia (sleeping too much)
• Appetite changes: Loss of appetite with weight loss or, conversely, overeating with weight gain
• Fatigue or loss of energy: Beyond the usual MS fatigue, exhaustion that does not improve with rest
• Feelings of guilt or worthlessness: Tendency to devalue oneself, to feel like a burden to others
• Concentration difficulties: Beyond the cognitive impairments of MS, inability to focus on anything
• Thoughts of death: Recurring thoughts about death, suicidal thoughts (a sign of severity requiring urgent help)

Treating depression to regain one's abilities

The good news is that depression is effectively treated, even in the context of MS. Several approaches, often combined, can help recover better morale and, at the same time, improve the cognitive functions altered by depression.

Psychotherapies

Psychotherapy, particularly cognitive-behavioral therapy (CBT), is recommended first for mild to moderate depressions and as a complement to medications for more severe depressions. CBT helps identify and modify automatic negative thoughts that fuel depression and gradually resume rewarding activities.

Other forms of psychotherapy can also be useful: acceptance and commitment therapies (ACT), mindfulness-based therapy (MBCT), interpersonal therapies. The choice depends on the person's preferences and the availability of therapists.

Medication treatments

Antidepressants may be necessary for moderate to severe depressions or when psychotherapy alone is not enough. Selective serotonin reuptake inhibitors (SSRIs) are often used first because they are generally well tolerated. The choice of medication and follow-up should be ensured by a doctor familiar with MS to avoid interactions with other treatments.

Physical activity as an antidepressant

Physical exercise has well-documented antidepressant effects, comparable to those of medications for mild to moderate depressions. It promotes the release of endorphins, improves sleep, boosts self-esteem, and provides a sense of accomplishment. For people with MS, suitable physical activity (walking, swimming, yoga, stationary biking) can be a valuable complement to the treatment of depression.

Cognitive stimulation as support

Once depression is addressed, cognitive stimulation with programs like EDITH and JOE can play an important supportive role. Cognitive exercises offer achievable daily goals, a sense of achievement, and can help regain confidence in one's abilities. They do not replace the treatment of depression but usefully add to it.

My psychiatrist prescribed me an antidepressant and recommended that I resume gentle physical activity. A few weeks later, I felt the fog lifting. I was then able to restart my exercises with EDITH, which I had completely abandoned during my depression. Today, these exercises are part of my daily routine and help me stay positive.

Pierre, 52 years old, MS for 15 years

Prevention and maintenance of psychological well-being

Beyond treating depressive episodes, it is important to implement strategies to prevent relapse and maintain a good psychological balance on a daily basis. These strategies are an integral part of the overall management of MS.

Building a support network

Social isolation is a major risk factor for depression. Maintaining social connections, even when the disease makes going out difficult, is essential. Family, friends, patient groups, associations: all forms of social connection matter. Do not hesitate to talk about your disease and your feelings with trusted people.

Engaging in meaningful activities

Having activities that are meaningful and provide pleasure is a protective factor against depression. Even if MS imposes limitations, it is often possible to find adapted activities: reading, music, gardening, volunteering, manual activities, cognitive stimulation with EDITH and JOE. The important thing is to maintain a sense of usefulness and accomplishment.

• Maintain a routine: A daily structure helps fight apathy and withdrawal
• Set realistic goals: Small achievable goals rather than overwhelming projects
• Practice gratitude: Writing down a few positive things each day helps counterbalance negative tendencies
• Expose to light: Natural light has positive effects on mood, especially in winter