Understanding Major Depressive Disorder: Causes, Symptoms, Treatment

Have you ever felt like a heavy cloud lingers over you, making it difficult to enjoy the activities you once cherished? Or, perhaps someone close to you seems caught in a loop of sadness and exhaustion. These could be signs of major depressive disorder—a serious, yet treatable, condition that reaches beyond the occasional down day or rough patch.

Dr. Muhammad Awais Aftab, psychiatrist with Southwest General Medical Group, offers important information surrounding major depressive disorder, including causes, what to look for, treatment options and patient outcomes.

Signs and Symptoms of Major Depressive Disorder

Major depressive disorder, one form of clinical depression, is one of the most common mood disorders across the world. Individuals often experience sleeping difficulties, changes in appetite or weight, reduced energy, increased feelings of guilt, low motivation, trouble concentrating, and, in some cases, suicidal thoughts.

“If these changes are persistent and ongoing, and if a person is experiencing low mood and loss of interest most of the time for at least a two-week period, then it enters the territory that we call major depressive disorder,” states Dr. Aftab. “There are other kinds of depressive disorders as well. But, major depressive disorder is the most common diagnostic category and the main form of clinical depression we recognize.”

What Causes Clinical Depression?

Major depressive disorder manifests in different ways. Some people have a more physical or biological representation of depression, where they experience a sudden onset of low mood, low physical activity. Often, there isn't any obvious trigger in their environment or in their social circumstances that seems to have initiated it. Among other people, a depressive episode is linked to some type of stressful life event.

“They might be experiencing relationship or marital difficulties. They might be experiencing financial difficulties. Those life stressors get to a point where they start feeling overwhelmed, and they enter a depressive episode,” explains Dr. Aftab.

In some individuals, the depressive episode arises from history of trauma or abuse, which resurfaces in adulthood. Certain people also are genetically predisposed to experiencing depression during moments of stress. And, select personality characteristics (e.g. those with neurotic traits) can trigger a depressive episode in circumstances that are “fine” for the general population.

Depression’s Impact on Daily Life

Unfortunately, major depressive disorder can be quite impairing for one’s personal and work life. Affected individuals often find themselves at a reduced level of functioning, and in severe cases, may have to take medical leave from their work or studies.

Dr. Aftab notes that there are milder forms of clinical depression in which a person can continue their everyday functioning. “They're feeling depressed, they're feeling distressed. But, they're able to, with effort, compensate for that and continue working. These are cases where depression can go undiagnosed for long periods of time. From outward appearances, it seems as if the person is doing okay. But subjectively, they're feeling very down, they're feeling very depressed and stressed. So, that can happen too.”

When Should People Seek Professional Help?

The right time to seek help for depression depends on the severity and impact of the symptoms. If someone experiences extreme symptoms, such as suicidal thoughts, they should seek help immediately, even if these feelings have lasted only a few days. The commonly referenced two-week guideline is used by clinicians to distinguish between brief, self-limiting episodes and more persistent forms of depression.

However, it’s not a strict rule. If someone’s daily functioning is severely impacted, or they have concerning symptoms like suicidal thoughts or major changes in energy, they should reach out for support regardless of the duration.

Treatment Options

The first step in treating depression is a thorough clinical evaluation to understand the specific symptoms and contributing factors and to rule out other medical and psychiatric conditions that might present with similar symptoms. Depression can sometimes stem from severe anxiety, substance use issues, or other medical issues like hormone or vitamin deficiencies.

Once major depressive disorder is confirmed, treatment options include psychotherapy and medications, both of which are well-researched for effectiveness. For mild cases, psychotherapy alone may suffice, while moderate to severe depression often benefits from a combination of medication and therapy.

“We have a number of medications available to treat depression,” assures Dr. Aftab. “They often have similar degree of effect, but they can differ in the side effect profile. So, that requires a discussion with the patient regarding what medications they may have tried in the past and what preferences they might have regarding potential side effects. Based on that discussion, a suitable antidepressant can be prescribed.”

Lifestyle changes also can play a valuable role in managing depression. Regular exercise, though challenging for those with low motivation, often significantly improves mood. Dietary improvements, such as reducing processed foods and sugars in favor of whole grains and less refined foods, also can positively impact mood. Additionally, practices like meditation, better sleep hygiene, time in nature, and social engagement are helpful. Since depression often leads to isolation, staying socially connected with friends and family can be a powerful support and mood booster.

Patient Outcomes

In terms of treatment outcomes, it really depends on the individual. Some people respond very well to medication—realizing benefits within three or four weeks. However, Dr. Aftab notes that is more the exception than the rule.

“I would say that happens but is less frequent. The more common scenario is that I see people improving and coming out of depression in a span of two to three months. Then, there are some people, about 15-20 percent, who have more prolonged forms of depression and who don't respond very well to standard treatments. For them, depression tends to be an ongoing issue, and it can last months.”

Recognizing Depression as a Signal

One recommendation Dr. Aftab offers for people with clinical depression is to not think of anxiety and depression in a negative pathological manner, because those symptoms are highly informative about what’s going on in our lives. He likens it to bodily pain that indicates a physiological issue.

“In the same kind of way, depression and anxiety can be signals that something has gone wrong in our lives, in our relationships. Psychotherapy and medication is helpful, but we also need to look for what it is in our life that has gone wrong and how can we set it right.”