What is depression?

It’s been estimated that nearly one in four women and one in six men experience at least one episode of depression in their lives.

Depression is a long period of a worsened mood. For some this may be a prolonged period of sadness and despair but for others it may be a feeling of numbness or feeling unable to experience pleasure. Some people express their sadness as anger or hostility. Depression weighs heavily on the body. causing very low energy, disruptions in sleep, weight gain or loss. Feelings of worthlessness or hopelessness can take over and disrupt normal functioning. Suicidal thoughts and ideation may occur.

Depression can be a single episode, for instance in response to a tragedy like a death, or it can be a recurring problem. When it is recurring, it could be part of Major Depressive Disorder. Of people who have had one episode of depression, 60% of people experience a second. Of people who had 2 episodes, 70% experience a third. Of people who experienced 3 episodes, 90% of them experience a fourth. Given the increased likelihood of relapse with each additional episode, prevention is really important after recovering from the first episode.

A depressive episode may be spontaneous, triggered by psychological causes, or triggered by physical causes, or some combination of those three. For instance, someone with an underlying predisposition to depression, can have a harder time recovering from a set back like the loss of a job.

Genetic factors can influence people to have certain thought patterns that are associated with depression. For instance people with a certain gene are more likely to ruminate – constantly worry about their problems and think of worst case scenarios, rather than think of solutions. Another gene makes it more likely to remember negative information. This is important in depression because depressed people have a tendency to be very good at remembering every time they failed and not so great at remembering their accomplishments, contributing to their belief that they’re worthless. One environmental factor is bullying during childhood. Not only does it increase the likelihood of depression, it also increases the likelihood of having negative thought patterns which overestimate how often bad things will happen. For instance, a negative situation could be caused by all sorts of reasons specific to that situation. People who develop depression tend to have thoughts which make them think they are failures or the problems aren’t just specific to that situation, but rather because of them.

Stress is often a trigger to a depressive episode. Major life events seem to be one of the most common stressors which trigger the first episode of depression. These include events like losing a job, having a serious medical diagnosis, having a major setback to your goals or plans. The loss of someone, whether it be because of death or break ups, is especially likely to trigger depression. Even the threat of losing someone can trigger depression. This can be particularly devastating to people who have a personality that likes being dependent on others and are scared of abandonment. Chronic stress lasting months or even years can also be a trigger.

One physical cause of depression is the lack of daylight, which can trigger seasonal affective disorder (SAD) in some people. Changes in the season mean changes in how much daylight please are exposed to per day. This affects levels of melatonin, a hormone that regulates sleep and mood. Another type of depression caused by changes in hormones is postpartum depression (PPD). For some new mothers, drastic changes in hormones caused by pregnancy or giving birth can trigger depression. Substance use can also trigger depressive episodes as a side effect. While some substances like alcohol can have depression as one of its effects, other drugs such as cocaine or ecstasy have depression as a symptom during withdrawal.

Substance abuse can also be a symptom of depression, as the depressed person uses drugs or alcohol to avoid facing their depression. This is, of course, a bad way of dealing with depression and will only compound the problem. Addiction is especially hard to overcome if also dealing with depression.

Depression is associated with a chemical imbalance in the brain. Scientists still aren’t sure the exact chemicals involved. Antidepressant medication typically target dopamine, serotonin, and norepinephrin. However, GABA and glutamate influence the levels of those neurotransmitters, and may also be involved. Some recent research suggests that an inflammatory response by the immune system may be an underlying cause of depression, but the evidence for it remains mixed. Antidepressants are effective at helping people recover from an episode of depression, while psychotherapy is particularly effective at preventing a relapse.

If you think you are suffering from depression, it’s important to speak to a mental health professional. In my next article, I will talk about some methods to cope with feelings of anxiety and depression.

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