Sad or SAD? Your guide to understanding depression

The teenager who is being bullied.

The breadwinner who was downsized and has yet to find a new job three months later. The new mother who is feeling moody, overwhelmed, and is having trouble sleeping. As humans, our feelings can vacillate between any number of emotions, but the one that might elicit the widest range would be sadness. Feeling sad because you lost someone in your life, lost your job, or are going through a stressful period is a normal reaction to events like these. If you’re feeling extremely sad, you might even say you feel “depressed.” But are you really? How do you know when extreme sadness crosses over into clinical depression?

Depression differs from sadness in both its persistence and pervasiveness. While sadness may feel all-encompassing at times, there should also be times you are able to laugh or be comforted. And, like all emotions, the sadness will eventually fade and you will bounce back. Depression, however, colors all aspects of your life a dull shade of grey. It may be hard or even impossible to find enjoyment in anything, including activities and people you used to enjoy. Episodes of depression can last at least 2 weeks at a time. They can be triggered by a sad event or they can seemingly come of out of nowhere. In short, depression is a mental illness, not an emotion.

Mental health professionals use the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to help determine if someone is sad or depressed. The DSM-5 criteria include nine potential symptoms of depression. The severity of each symptom is assessed and additionally, the symptoms must not be a result of substance abuse or another medical condition. An individual may receive a diagnosis of clinical depression or major depressive disorder (MDD) if he/she experience five or more of the following symptoms during the same 2-week period, with at least one of the symptoms being a depressed mood or loss of interest or pleasure. The nine symptoms are:

Feeling depressed throughout each day on most or all days

Lack of interest and enjoyment in activities that were once found to be pleasurable

Trouble sleeping, or sleeping too much

Trouble eating, or eating too much, coupled with weight gain or weight loss

Irritability, restlessness, or agitation

Extreme fatigue

Unwarranted or exaggerated feelings of guilt or worthlessness

Inability to concentrate or make decisions

Thinking a lot about death and dying and/ or suicidal thoughts or actions

When people use the term clinical depression, they are generally referring to major depressive disorder (MDD), as described above. However, there are many different types of depression that can make daily life difficult. Each type often has different causes, but they typically involve a loss of interest in activities that the person once loved and an overall feeling of melancholy.

Persistent Depressive Disorder (PDD, also called dysthymia) is a mild to moderate depressed mood that lasts for at least two years. Many people with this type of depression describe having been depressed as long as they can remember. A person diagnosed with PDD may have episodes of major depression along with periods of less severe symptoms, but symptoms must last for two years in adults and at least one year in children and teens to be considered PDD.

Formerly referred to as postpartum depression, peripartum depression disorder (PPD) is full-blown major depression that women experience during pregnancy or after delivery. (The name change reflects the new recognition that depression and anxiety can also manifest during the pregnancy itself). While nearly 70% of all new mothers experience the “baby blues” after giving birth due to rapidly fluctuating hormone levels, the feeling generally subsides in about two weeks; however, for some women, the symptoms of depression can become more severe and last much longer. Left untreated, peripartum depression can affect not only the well-being of the mother but also that of the child. It can cause premature birth and low birth weight, and the feelings of extreme sadness, anxiety, and exhaustion after birth can cause mother-child bonding issues and can contribute to sleeping and feeding problems for the baby. In the long term, children of mothers with peripartum depression are at greater risk for cognitive and emotional development issues, as well as verbal deficits and impaired social skills.

Seasonal affective disorder (SAD) is characterized by the onset of depression during the winter months, when there is less natural sunlight. Those who reside in areas where there is little sunlight, will usually have a higher incidence of SAD. In SAD, winter depression predictably returns every year at around the same time, typically accompanied by social withdrawal, increased sleep, and weight gain. The depression generally lifts during spring and summer; however, some people can experience SAD in the spring or early summer.

Psychotic Depression occurs when a person has severe depression plus some form of psychosis, such as hallucinations (seeing or hearing things that aren't there), delusions (false beliefs), and paranoia (wrongly believing that others are trying to harm you).

Bipolar disorder is different from depression, but is included in this list since individuals with bipolar disorder experiences episodes of extremely low moods that meet the criteria for major depression (called “bipolar depression”). However, a person with bipolar disorder also experiences extreme high – euphoric or irritable – moods called “mania”.

Depression is a complex illness that can have many triggers. There are even times when people are depressed for no clear reason. Some people and personalities are more prone to experience depression. For example, individuals who have low self-esteem, who are perfectionists, and who are sensitive to criticism are naturally more likely to be depressed. Although a gene has yet to be discovered that is directly linked to depression, individuals with a family history of depression are more likely to also experience depression. Whether this trend is due to biology or learned behavior is still open to debate.

Sometimes, depression happens because of a major illness or chronic

health issue that drastically changes the person’s lifestyle. Ironically, the depression often aggravates the condition, as it can intensify pain, as well as fatigue and sluggishness. The combination of chronic illness and depression can cause people to isolate themselves, which is likely to exacerbate the depression and a downward spiral ensues. Depression rates are high among patients who have a heart attack, cancer, diabetes, chronic pain syndrome, impaired thyroid function, and other conditions.

Depression can also be an unfortunate side effect of some medications. Additionally, nearly 30% of people with substance misuse problems also have major or clinical depression. Even if drugs or al - cohol temporarily make the individual feel better, they ultimately will aggravate depression.

Negative life events such as losing a job, being in a dysfunctional relationship, stress at work, divorce, and bereavement can increase a person’s chances of being depressed; however, it’s often the way a person deals with these difficult situations that determines whether or not depression develops and not the event itself.

Depression can have a biological base. Researchers have noted differences in the brains of people who have clinical depression compared with those who do not. Since the brain plays a major role in the control and balance of emotions, research in brain chemistry is the key to understanding how and why depression develops in the first place. Neurotransmitters are chemical messengers which carry signals between nerve cells in the brain. Researchers now believe that when the body produces low levels of the neurotransmitters norepinephrine, serotonin, and dopamine, among others, nerve cell communication in the brain decreases. Researchers aren’t entirely sure what lowers the levels of these neurotransmitters— biology or the stress hormone cortisol are some possibilities—but what is known is that when this happens, the brain may not receive the signals it needs to know when to fight, flight, experience pleasure, sleep, eat, reduce pain, or ease anxiety. This disconnect can cause a person to experience symptoms of depression like insomnia, decreased appetite, or irritability.

Often, the biggest hurdle to diagnosing and treating depression is recognizing that someone has it. Unfortunately, about half of the people who have depression never get diagnosed or treated. Once diagnosed, depression is very treatable and most people see improvements in their symptoms with lifestyle changes, psychotherapy, medication, or a combination of the three.

If depression is suspected, a visit to a primary care doctor is recommended. The doctor will do a physical examination, review all medications that are being taken, discuss any family history of depression or other mental illness and possibly run some lab tests to rule out other conditions that may cause depression such as a virus, hormonal or vitamin deficiency, or illnesses. The doctor can also refer the person to a mental health expert like a psychiatrist, psychologist or a therapist for treatment.