Depression is commonly referred to as a mood (affective) disorder. Hallmarks of depression include a low or sad mood, irritability, pessimism, decreased or absent interest in almost all activities, loss of self-confidence, and a feeling of worthlessness. Other features often include fatigue, sleep disturbance, and appetite changes.
There are actually a number of different types of depression. In the classic type, called major depressive disorder, the symptoms are usually episodic—that is, bouts are separated by symptom-free periods characterized by feelings of relative well-being.
Major Depressive Disorder: Telltale Symptoms
More than 10 percent of American adults have at least one episode of major depressive disorder each year. Here are the symptoms.
A combo of causes: from genetics to hormones
The exact causes of depression are not well understood, but some combination of genetic predisposition and psychological and physiological factors appears to play a role.
Depression is often a family affair. Scientists have found a common genetic mutation associated with clinical depression after a traumatic event. Although genetic factors may make a person more susceptible to mood disorders, a precipitating event—such as a serious medical condition or psychological stress—often causes a mood disorder to emerge at a specific time.
Medical disorders can make people prone to depression. For example, people who have disorders such as Alzheimer’s, Huntington’s, or Parkinson’s disease are more susceptible to depression. So are patients who have had a stroke in the left frontal area of the brain. Hormonal disorders, such as an underactive thyroid (hypothyroidism) and Cushing’s disease, also can lead to depression.
Depression is common in women who are pregnant and after birth, affecting about one in seven women during either period. During pregnancy, hormonal changes affect the brain. After childbirth, hormone levels quickly change, causing other chemical changes that can be exacerbated by the challenge of getting adequate rest to fully recover from giving birth.
Vitamin deficiencies, such as insufficient levels of folate, vitamin B6, or vitamin B12, have also been linked to depression.
The combination of elevated cholesterol, blood pressure, and blood sugar plus obesity (metabolic syndrome) is associated with risk for depression. There is also evidence that obesity alone increases the risk. Prescription drugs can cause mood disorders, too. For example, some drugs used to treat high blood pressure and cancer can cause depression.
Persistent Depressive Disorder Needs Treatment
Persistent depressive disorder may be less severe than major depressive disorder, but it still calls for treatment.
A particular type of depression, called seasonal affective disorder (SAD), is associated with seasonal changes in the amount of daily sunlight. Sunlight variations cause changes in our internal biological clocks (also called circadian rhythm). In some people, less daily sunlight and changes in circadian rhythm can induce depression, which is usually worst during the shortest days of winter. Researchers believe that the lack of sunlight during these times may alter brain levels of certain moodcontrolling substances.
People with SAD often eat and sleep excessively and crave sugary or starchy foods. They typically have a full remission in the spring and summer, when more sunlight is available. Unlike other forms of depression, SAD may be treated with light therapy.
Depression in older adults
The “golden years” come with concerns that can often lead to depression: financial worries in retirement, loss of independence, illness, fears of mortality. Depression in older adults sometimes has such obvious causes but, as at any age, it often comes out of nowhere.
Some signs and symptoms of depression in older adults are more subtle or mimic those of other medical conditions, according to a review published in the Journal of the American Medical Associationin 2017. Drug side effects can also induce or mimic depression. And memory problems from depression can be difficult to distinguish from dementia.
Chronic illnesses or other health problems can contribute to depression—particularly if those conditions limit daily functioning. Roughly 80 percent of older adults have at least one chronic health problem, according to CDC data, and about twothirds live with multiple chronic ailments. In a 2010 study published in Ageing Research Reviews, factors associated with increased risk of depression among older adults included stroke, loss of hearing, poor eyesight, heart disease, diabetes, and chronic lung disease. And health problems that limit physical abilities can decrease a person’s ability to participate in his or her community, leading to the social isolation that itself is a risk factor for depression.
The loss of a spouse, other family members, or friends can have a lasting impact beyond the sadness of grieving. Such losses also disrupt a person’s social structure; with fewer companions, people can become increasingly isolated, which can trigger or exacerbate depression. Conversely, evidence has shown that older adults who have strong social ties and a sense of community are less likely to experience depression and tend to be physically healthier. Staying physically active and seeking out intellectual stimulation and challenges can also be protective.
Many older adults mistakenly believe their depression is just a normal result of getting older. Others tend to be embarrassed or reluctant to seek professional help for emotional problems. Or they may remember the days when treatments were less effective.
Depression can induce hopelessness and undermine the initiative to seek help or continue in treatment. Unfortunately, most cases of late-life depression are inadequately treated—or not treated at all. Many older adults are treated with doses of antidepressants that are too low, or treatment is stopped too early.
Untreated depression is likely to intensify and can worsen coexisting conditions like diabetes and high blood pressure, making them harder to control. It can indirectly harm well-being by leading people to not take care of themselves—skipping their medications, eating poorly, not exercising, and so on. Depression may increase certain inflammatory processes that underlie many medical conditions.
If you think you may be experiencing depressive symptoms, discuss your concerns with your doctor or another health professional. Getting the right treatment will help you manage symptoms and likely improve your quality of life. And once you find relief, you still need to be alert for returning symptoms.
If depression is diagnosed, treatment options include antidepressants, psychotherapy, or a combination of both. In addition to conventional treatments, exercise has been shown in numerous studies to help combat depression, in part by boosting the levels of neurotransmitters that affect mood and by providing an activity (often a social one) outside the home.
Other lifestyle changes, such as eating a healthier diet, avoiding processed and sugary foods, and adopting a more regular sleep schedule, can help. It’s a good idea to eliminate or limit consumption of alcohol. While many older adults use alcohol to mask or cope with depressive symptoms, alcohol can exacerbate depression, creating a vicious cycle.
This article first appeared in the UC Berkeley Wellness Letter.
Also see How to Get Mental Health Help.
Published July 23, 2018