Depressive disorders are characterized by a notable disturbance in mood, primarily manifesting as persistent sadness, emptiness, or heightened irritability. Individuals grappling with these conditions frequently undergo significant physical changes, such as disruptions in sleep patterns (ranging from insomnia to excessive sleepiness), altered eating habits (either overeating or loss of appetite), and fluctuations in energy levels. Cognitive functions are also often impacted, leading to difficulties in concentration, indecisiveness, and even morbid thoughts, including thoughts of death.
Major Depressive Disorder (MDD) is marked by an overwhelming sense of sadness or anhedonia – a pronounced loss of interest in previously enjoyable activities. This core symptom is accompanied by substantial shifts in both physical and cognitive functioning. For a diagnosis of MDD to be established, these symptoms must be consistently present, nearly every day, for a minimum period of two weeks. Persistent Depressive Disorder (PDD), also known as dysthymia, shares similar symptoms, including a pervasive sad mood and difficulties in physical and cognitive functioning, but these occur more days than not for at least two years in adults, or one year in children and adolescents. Disruptive Mood Dysregulation Disorder (DMDD) is a distinct diagnosis specifically for children under the age of 12. It is characterized by persistent irritability and extreme behavioral dyscontrol, often expressed as frequent temper outbursts.
In younger populations, depressive disorders can be easily overlooked. This is primarily because they are internalizing disorders, meaning the symptoms are primarily experienced internally, rather than externally expressed. In contrast, many other childhood disorders are associated with externalizing symptoms, such as hyperactivity or aggression, which are more readily noticed by parents and educators. DMDD is an exception due to its characteristic temper tantrums; however, these outbursts can sometimes lead to misdiagnosis, often being mistaken for oppositional defiant disorder or bipolar disorder, when they may actually stem from an inability to effectively communicate internal emotional distress.
Major Depressive Disorder is typically episodic. While some individuals may experience only a single episode in their lifetime, the majority will face recurrent episodes of depression. This pattern may be particularly pronounced in children and adolescents, with those experiencing depression in their youth being more likely to struggle with depressed mood into adulthood. In contrast, both Disruptive Mood Dysregulation Disorder (DMDD) and Persistent Depressive Disorder (PDD) are considered more chronic conditions. For a diagnosis of DMDD or PDD, symptoms must be present for at least one year, with no more than two consecutive months of being symptom-free. While DMDD and PDD can be longer-lasting than an episode of major depression, the severity of symptoms is often less intense. DMDD is primarily defined by persistent irritability and frequent temper tantrums. PDD, symptomatically, is more akin to major depression – young individuals with PDD experience a persistent sad or depressed mood alongside physical and cognitive symptoms.
All depressive disorders signify a change from previous functioning. Even though PDD and DMDD have a more chronic course, all three – MDD, PDD, and DMDD – are episodic in nature. This means that even in PDD and DMDD, defined by prolonged periods of low or irritable mood, the conditions are episodic because there is a discernible change in functioning at the onset of the illness, and the expectation is that symptoms will eventually lessen or remit, potentially with appropriate intervention and support. Fluctuations in symptom severity are common across all depressive disorders, influenced by time, life events, and treatment interventions. Many individuals with depressive disorders also report significant somatic symptoms, and young people in particular may complain of physical ailments like headaches or stomach aches, alongside pervasive low energy. Furthermore, hopelessness and suicidal ideation are significant concerns for many young people diagnosed with a depressive disorder. The risk of suicide in this population is a serious issue that requires close monitoring and proactive intervention.
