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A Surprising but Important Sign of Depression

Dysregulated sleep and appetite can push a depressed person to lash out.

Key points

  • Depression is often misperceived as a sad, withdrawn, suicidal state, but anger and aggression can be part of the depressed experience.
  • Neurochemistry, dysregulated sleep and appetite, and stimulation-seeking can contribute to aggression while depressed.
  • Prominent aggression can trigger assumptions of personality or impulse control pathology, but should first lead to evaluation for depression.
Nathan Dumlao/Unsplash
Source: Nathan Dumlao/Unsplash

Depression, like many mental illnesses, has an inaccurate stereotype. The deflated, sobbing, suicidal profile depicted in popular culture is not untrue, but it is by no means the only depressive experience. Even the different subtypes of depression exist on continuums and can be expressed differently in different people.

While the Diagnostic and Statistical Manual (DSM) has for decades provided descriptions of various depressive disorders and their subtypes, it still fails to address a key fact that experienced clinicians recognize and that has been put forth by numerous researchers over the years (e.g., Rosenfeld, 1959; Dutton & Karakonta, 2013; Meyrueix et al., 2015; Krakowski & Nowlan, 2017): Aggression is not an unusual indicator of depression. So prevalent this is, that, in 2001, the researcher van Praag suggested a new depression diagnostic consideration based on unique biomarkers behind many people who tend to be aggressive while depressed.

Perhaps the closest the DSM-5 (page 163) comes to recognizing aggression as a symptom of depression is noting that irritability, described as "... persistent anger, a tendency to respond to events with angry outbursts or blaming others, or an exaggerated sense of frustration over minor matters," is not uncommon. While aggression is recognized in disruptive mood dysregulation disorder of childhood (DMDDoC), a depressive condition, with its trademark tendency for explosive reactivity, it is limited to ages 7-17.

Consider, however, what happens when this child "ages out" of DMDDoC, and angry, depressed adults exhibit aggressive acts? It's been my experience that this can lead clinicians to immediately wonder about personality disorders or jump to considering an intermittent explosive disorder diagnosis.

If it is not recognized that the aggression may be a sign of depression, chances are treatment will focus on "anger management," which will provide some coping skills, providing tenuous stability at best. Stability from anger management coping skills is likely tenuous because it's akin to cutting down a weed instead of pulling out its roots. The anger, like a weed, will grow back because its root, the depression, has not been eradicated.

How Depression and Aggression Are Related

  1. Neurochemistry: It's no secret that lower levels of serotonin, a serenic, "down-regulating," or "feel-good" neurochemical, are associated with the dysphoria (unpleasant mood) of depression. Thus, it's easy to see how a dearth of an essential stable mood contributor and impulse control regulator (e.g., Seo et al., 2008; Celada et al., 2013) could lead to irritability/anger, and aggression. It has also been long known that depression is correlated with disruptions in the hypothalamic-pituitary-adrenal (HPA) axis, which governs hormones, which help govern mood, aggression, sleep, and appetite.
  2. Poor sleep: Depressed people tend to experience insomnia, and it is well-documented that insomnia and irritability/anger are associated (e.g., Saghir et al., 2018; Kim et al., 2019). If you've ever encountered remarkably poor sleep, you can see how chronic insomnia just adds to the frustrations of the depressed person, lending itself to reactivity. Further, poor sleep is associated with elevated amygdalar reactivity (e.g. Prather et al.; 2013; Saghir et al., 2018), which, given the amygdala regulates response to threats, not uncommonly is in the form of anger/aggression.
  3. Appetite disturbance: People with depression tend to experience appetite changes, often in the form of eating less. As noted in detail in "Two Overlooked Causes of Anger," and in recent research by Swami et al. (2022), "hangriness" is real. Brains need a particular amount of glucose to function, and if sufficient food isn't ingested to sustain this, the body pillages and loots for it. One way this happens is by releasing hormones that contain glucose (e.g., Cleveland Clinic, 2021) to mine them for it. Two of these are the excitatory hormones cortisol and adrenaline, which are associated with inflamed tempers (e.g., Leggett et al., 2015; Cleveland Clinic, 2021).
  4. Stimulation-seeking: As written about in "An Unusual, Overlooked Sign of Depression," while depression and excitement seem like strange bedfellows, some depressed individuals discover that they can perk themselves up by engaging in thrill-seeking activities, including fighting. With fighting, they not only discharge their negative emotions, but the painful physical activity, similar to cutting, allows them to actually feel something other than affectively flat or dysphoric. If they are good at fighting, it can also inject a depression-fighting dose of increased self-esteem.
Source: Cottonbro/Pexels

Treatment Implications

First, like any diagnosis, it's important that conclusions not be jumped to and a thorough evaluation takes place when pervasive anger/aggression is encountered. Though such a presentation can be a chief attribute of certain personality disorders or intermittent-explosive disorder (IED), for example, a question of affective disorder should also be on the evaluator's mind. First, however, it must be clear that the aggression does not only coincide with a current manic/hypomanic phase of bipolar disorder, or perhaps hallucinatory content or delusional beliefs associated with psychosis.

Next, if the person meets the general depression criteria, and lacks clear evidence of borderline, antisocial, or narcissistic personality disorders, or the aggressive incidents are more frequent and generally less severe than IED, these are good indicators that aggression can be addressed by managing the depression. Even if it is discovered that the person meets criteria for one of these other conditions, considering that depression can contribute to anger and aggression, it obviously can exacerbate the other clinical concerns.

Second, given the heft of influence that appetite and sleep disturbance can have on encouraging anger/aggression in depression, it makes sense that this is a considerable focus of intervention. Referral to a psychiatrist for pharmacological evaluation is one step in regulating the neurovegetative symptoms likely contributing to the picture, while making sleep hygiene and diet another part of the intervention. The former may be addressed in therapy sessions, of course, while the latter should be met through referral to a nutritionist, as discussed in Three Powerful Adjunctive Therapies That May Help With Depression and Anxiety.

Finally, exploration of the meaning of the aggression may prove helpful. Therapists working with aggressive, depressed patients may want to ask how the aggression is internally experienced. It's been my experience, for example, that some aggressive, depressed individuals are trying to express in action what is not able to be verbally articulated. While the aggression may be somehow satisfying in the moment, later it is ruminated on as another sign that they are inherently not a good person or similar, adding interest to the principal depressive experience. It is quite possible they are, for instance, projecting their self-hatred onto others, assuming others are slighting them as they slight themselves, and delivering the punishment elsewhere. Exploring and discovering more constructive ways to express and resolve their conflicts could significantly disrupt the cycle.

Disclaimer: The material provided in this post is for informational purposes only and not intended to diagnose, treat, or prevent any illness in readers or people they know. The information should not replace personalized care from an individual's provider or formal supervision if you’re a practitioner or student.

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