It’s natural to assume that anxiety and depression are very different. The sadness and lethargy typical of depression seems nothing like the fearful agitation associated with anxiety disorders. Indeed, they appear in separate chapters of The Diagnostic and Statistical Manual of Mental Disorders.
But perhaps this scenario sounds familiar: An anxious teen avoids a challenging assignment or an interaction with a new group of peers. Before long, they face a mountain of missing work or find themselves left out of social opportunities. They become overwhelmed by despair and shut down in a state of depression. Or it might go the other way—over time, the effects of depression (such as social isolation or being bullied) turn into a source of anxiety.
These examples illustrate two of the ways in which these seemingly different disorders of depression and anxiety can be interrelated. And when they occur together, which is known as “comorbid” depression & anxiety, they are far more difficult to treat than either condition on its own.
Signs of Depression and Anxiety Disorders
Experts acknowledge that one reason depression and anxiety are frequently diagnosed together may be the way they are described in the diagnostic manual. We are used to thinking of the signs and symptoms of depression and anxiety separately. Excessive worry is unique to anxiety and the inability to feel pleasure is unique to depression. However, there are several symptoms that overlap between the two disorders, including:
- Sleep disturbances (either too much or too little)
- Difficulty concentrating
More broadly, both disorders can be said to cause a general sense of distress. Could they in fact be similar in ways that are important for treating them when they occur together? Many researchers are now looking at the shared features of the two disorders, rather than the ways in which they differ. This may yield a promising approach to treatment of Major Depressive Disorder (MDD) and Generalized Anxiety Disorder (GAD) as a dual diagnosis.
Adolescent Anxiety and Depression Statistics
The pandemic and its associated social disruptions have fueled dramatic increases in child and adolescent depression and anxiety. One in four teens surveyed in 2021 self-reported feelings of general anxiety and depression. This prompted the declaration of a national emergency by the American Academy of Pediatrics and other child health professional organizations.
However, the youth mental health crisis began before the pandemic. A recent analysis of federal data from 2013–2019 found the following adolescent statistics on these joined disorders.
- Nearly 1 in 10 children ages 3-17 (9.8 percent) were diagnosed with anxiety.
- More than 1 in 5 adolescents ages 12–17 (20.8 percent) were diagnosed with depression.
- More than a third of high school students (36.7 percent) self-reported feeling persistently sad or hopeless, and half of those (18.8 percent) seriously considered suicide.
What Comes First: Anxiety or Depression?
Researchers describe three pathways for the development of comorbid mental health disorders:
Anxiety starts before depression.
As in the example above, untreated anxiety can produce behaviors that increase the risk of depression. This pathway is the most common progression. Studies show that anxiety disorders usually begin during preadolescence and adolescence. Major depression, on the other hand, more commonly appears during adolescence and young adulthood.
Depression starts before anxiety.
Depression can sometimes occur before anxiety. This is less commonly diagnosed, however, because the early symptoms of depression are sometimes subtle. Also, depression in children often looks like the irritability of anxiety instead of more typical depression symptoms.
Depression and anxiety originate at the same time.
Rather than one disorder influencing the onset of the other, in some cases these disorders can develop at the same time. Experts think that this happens when a person’s stress-response system malfunctions in ways that produce the symptoms of both disorders.
The Relationship between Anxiety and Depression
Anxiety & depression (along with PTSD) are sometimes dubbed “the stress-related disorders.” Both genes and stress contribute to the likelihood someone will develop the conditions. But neither factor alone can be said to cause the disorder. These are both only “moderately heritable,” with a 40-50 percent likelihood if a close family member has one or the other. And challenging life experiences do not necessarily cause mental health issues. One person may experience an event as stressful that someone else does not. It depends on their neurobiological makeup and/or sensitivity from past experiences.
Experiencing some degree of depression and anxiety symptoms can be a normal human response to life stress. In healthy people, these symptoms reflect our physiology working as it should. A degree of anxiety helps us mobilize the energy to do what we need to do and anticipate obstacles, for example. The low energy and sadness characteristic of depression are appropriate when we need to heal from illness or injury or adapt to a loss. The symptoms of depression and anxiety become problematic, however, when they persist even without an obvious stressor and get in the way of daily functioning.
How do these naturally protective processes turn into clinical disorders? It depends on many factors, and much is still unknown. Breakthroughs in genetics and brain imaging are helping experts develop a clearer understanding of the varied factors that contribute to both depression and anxiety. Usually the answer is not simply an imbalance in brain chemistry or the effect of a particular gene. Rather, anxiety and depression are expressions of a complex interplay of genetics, neurobiology, and life experiences.
How the Stress Response System Underlies Anxiety and Depression
Our stress response system is fundamentally similar to that of other mammals. Like other animals, our body’s autonomic nervous system is constantly scanning our surroundings for potential threats even without our awareness. Unlike animals, however, human defense systems can be triggered by threats that exist only in the mind. Memories of past events or worries about an imagined future can arouse in humans the same physiological response as an actual threat.
Once a threat is detected—whether it’s real, exaggerated, or anticipated—the body immediately and automatically engages the threat response system in a “defense cascade.” Commonly known as “fight, flight or freeze,” the different states of the defense cascade follow a predictable sequence, with different mental and physical effects. These various stress responses can trigger psychological processes that lead to anxiety & depression.
Both genetics and past experience can influence a person’s sensitivity to threat. An individual’s inherited neurobiology or past trauma can set them up for greater sensitivity. Thus, they will be more likely to find themselves emotionally triggered. That sensitivity may also make the sensations of an activated stress response system harder to tolerate.
What Makes Someone Vulnerable to Anxiety and Depression?
There are three primary factors affecting someone’s vulnerability to these two disorders:
Genetics researchers have found that instead of a single gene for anxiety or depression, thousands of genes each contribute a small effect. Furthermore, recent advances in the field of epigenetics show that lived experiences can change the way that genes are expressed. Many of those genes are associated with both depression and anxiety, suggesting that the disorders are related. Studies with twins have shown that both disorders are clearly linked to shared genetics.
Genes affect the functioning of the many interrelated parts of the stress-response system. This includes the size and development of critical parts of the brain, such as the fear center of the amygdala and the emotion-regulation center of the prefrontal cortex. Genes also help control the production and reception of the chemical neurotransmitters that allow brain cells to communicate with each other. And they influence the glands and hormones that produce physical responses to threat.
General psychological vulnerability
General temperament, which is produced by both genetics and life experiences, helps determine a person’s likelihood of developing depression and anxiety. A noticeable tendency toward a particular set of personality traits often predicts the development of depression and anxiety. These traits include:
- Reacting to a variety of situations with negative emotions (including anger, anxiety, self-consciousness, irritability, and depression)
- Responding poorly to stress in their environment
- Interpreting ordinary situations as threatening
- Experiencing minor frustrations as hopelessly overwhelming
Specific vulnerability from life experiences
Whether or not genetic and temperamental vulnerabilities develop into anxiety, depression, or both, depends on the degree and timing of traumatic experiences. Too much adversity, too early in life can activate the stress response system and overwhelm its normal functioning. Consequently, the nervous system gets “stuck” in a defensive response. And, if it lasts too long, that stuckness can actually cause changes in the brain—changes that increase an individual’s vulnerability to depression and anxiety.
The Adverse Childhood Events Screening (ACES) has become a valuable tool for identifying patients who have been exposed to potentially toxic levels of stress. A high ACES score is linked to long-term physical and mental health problems in adults. A recent study also demonstrated that youth with four or more ACES were more than twice as likely to have anxiety and more than four times as likely to have depression.
How to Help a Teenager with Anxiety & Depression
The symptoms of either anxiety or depression can lead to the development of the other disorder. And they are more difficult to treat when they occur together. For these reasons, early signs of anxiety or depression in a child or teen should be taken very seriously.
An assessment by a mental health professional can help identify the root causes of the symptoms. A clinician will typically assess a client’s three areas of vulnerability—family history, individual temperament, and life experiences. Treatment should address the underlying issues causing either anxiety or depression. One goal of treatment is to reduce the chance that anxiety or depression will develop into a dual diagnosis.
At Newport Academy, we take an integrated approach to treating teen mental health conditions, including depression, anxiety, and the co-occurring disorders catalyzed by these disorders. Our treatment model is proven to reduce anxiety and depression while increasing adolescents’ well-being.
Contact us today to learn more about how our clinical model supports teens to find hope, connection, motivation, and excitement for what the future holds.
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