Genetic, neurobiological and environmental factors contribute towards the genesis of depressive disorders. This brief review aims to emphasize studies on the genetic, neurochemical and neuroanatomical causes of depressive disorders. The paper also seeks to explore the etiology and pathophysiology of depression and its implications in the development of new treatment methods. It seeks to emphasize the limitations of past and present studies on depressive disorders by establishing a common etiology for depression. Historically, depressive disorders have been worsened by difficulty in diagnosis and heterogeneity. Prospects for future research are also highlighted in the essay.
One of the historical consequences of depressive disorders is mood swings. It is usually experienced in form of sadness, irritability, hopelessness, loss of interest or displeasure (Boschloo, van, Penninx, Wall & Hasin, 2012). It may pose the risk and possibility of suicide. Therefore, it requires immediate treatment. Risk factors for suicide are affected by family history of depressive disorders, history of suicide attempts, puerperal period, comorbid medical illness, lack of social support, stressful or negative life events, active alcoholism and substance abuse (O’neil, Podell, Benjamin & Kendall, 2010).
In the case of previous suicide attempts or existence of attempts on family history, one has to be careful with the improvement observed after a certain time especially after the use of anti-depressants. A pharmacological approach in the management and treatment of depressive disorders is facilitated through the use of antidepressants and varies with the symptoms being displayed. The social safety net is of fundamental importance in the recovery process and strengthening of these patients.
Causes and pathophysiology
The actual causes of depressive disorders are complicated and sometimes unknown. The current explanatory model combines genetic predisposition that interacts with stressors. The environment seems to influence the onset and development of depressive disorders although there is no direct causal relationship. In specific cases of extreme situations (such as sexual violence), a clear trigger or relationship can be pointed out.
A number of transformations take place in the brains of patients with depressive disorders. The most consistent include volumetric reduction in the dorsolateral prefrontal and anterior cingulate cortex. Reduced activity is witnessed in the anterior cingulate cortex, and the hippocampus subgeminal area encounter increased activity in the amygdala. Hormonal changes are also common among patients diagnosed with depressive disorders (Beesdo et al., 2010).
Depressive disorders refer to subsets of mood disorders. They were formerly referred to as affective disorders. Mood disorder is one of the best-known psychic dimensions. However, it is one of the hardest aspects to define. To begin with, it can be perceived as an enduring affective state that permeates the behavior and efficiency in an individual mode. This reaction may consist of varying degrees of joy, sadness, indifference, irritability among others. Mood disorders are also part and parcel of depressive disorders. Depressive disorders may be subdivided according to the course, intensity and duration of symptoms, predominance of certain symptoms as well as the time of onset or emergence of episodes. Stroke refers to the number of episodes (Beesdo et al., 2010). It may be more than one episode. In the case of several episodes, it is called recurrent depressive disorder. According to the intensity of symptoms, it may be classified as mild, moderate or severe.
In regards to prevalence of symptoms, depressive disorders are named according to the predominant set of symptoms. For example:
- Melancholic depression with predominant vegetative symptoms (insomnia and loss of appetite) and circadian characteristics (worse in the morning);
- Atypical depression (excessive drowsiness and increased appetite);
- Pseudo dementia (symptoms of cognitive impairment);
- Psychotic depression (presence of delusions and / or hallucinations).
In addition, some episodes appear at certain times as seasonal depression and postpartum depression. When there is need to investigate the genetic component of depression, one of the main challenges is precise characterization of the phenotype. The latter characteristics are called observable phenotype in an individual who intends to relate to a particular genetic makeup. In the specific case of depression, even with current operating criteria, the reliability of diagnosis between different interviewers varies greatly depending on the number of episodes and severity. Thus, recurrent mild depressive episodes have low reliability while a single episode may pose serious effects. In addition, there are reports that show that the reliability of diagnosis of a depressive episode in a period exceeding one year within non-clinical populations is very low (Sarkar, Sinha & Praharaj, 2012). Therefore, differences in the conceptualization of the disorder can cause significant changes in the results of genetic research.
Some symptoms witnessed in patients with depressive disorders include loss of appetite, changes in sleep patterns, reduced ability to concentrate, fatigue, suicidal ideation or planning as well as guilt and worthless ideas. Depressive Disorders still do not have clearly established etiology. Most accepted theories highlight biological, environmental and hereditary factors as the etiology of depressive disorders. The depressed patient may show symptoms of disturbance, poor attention and concentration, a depressed or angry mood, slowed thinking process, guilt and even suicide (Gomez, Vance & Gomez, 2014). There may be a change in sensory perception (hallucinations). The appearance can also show some signs. These include an unshaven hair, disheveled hairstyles or little eye contact as well as head and psychomotor retardation.
The diagnosis of depressive disorders is purely clinical based on the history and symptoms. There is extensive evidence on the existence of brain disorder function and structure as well as neuroendocrine, inflammatory changes that take place when an individual is affected by any form of a brain disorder. In most instances, patients report reduced activity, loss of initiative, sadness, sleep disturbances and loss of appetite, sexual disorders (mainly loss of libido), and lack of pleasure among others.
Depressive disorders present themselves in different types. First, the atypical depressive disorder may be managed by exposing a patient to a positive occurrence. In other words, the mood is improved by a decent event. Situational depressive disorder depends on the case or event at hand. It takes place when an individual faces a difficult or disturbing circumstance in life. In the case of Premenstrual Dysphoric Disorder (PMDD), a patient may possess a feeling of being defeated, or develop anxiety and mood swings. Other types include Postpartum Depressive disorder, Psychotic Depression, Seasonal Affective Disorder (SAD), Bipolar Disorder, and Persistent Depressive Disorder.
Although it might be cumbersome to prevent certain types of depressive disorders, it is still possible to prevent a number of conditions from recurring. Some of the preventive measures include working together with others, securing leisure time, avoiding overworking, adequate relaxation, fun, regular exercise, and a healthy diet.
Treatment plans for short-term goals and long-term goals
The treatment of depressive disorders includes the use of psychotherapy, pharmacotherapy and the non-drug treatments. Several psychotherapeutic approaches may be used to treat depressive disorders according to the severity of the condition, its characteristics and the presence of stressors. Dynamic cognitive – behavioral approach and interpersonal factors are among the common family or group therapies that can be helpful in managing or treating quite a number of depressive disorders. Medications or a combination of medicine and psychotherapy is the most common contemporary treatment approach. Several types of drugs are available (Taylor-Clift, Morris, Rottenberg & Kovacs, 2011). They vary according to their primary modes of action and the profile of side effects.
The most widely used drugs are serotonin reuptake inhibitors (such as Fluoxetine, sertraline, paroxetine), dopamine and norepinephrine reuptake inhibitors (bupropion) relative inhibitors of serotonin and norepinephrine uptake (such as duloxetine). The common feature of all these drugs is the ability to increase neurotransmitter concentration in the synaptic cleft with the possibility or probability of intercellular effects. In some cases, the efficacy of drug therapy may be limited. Hence, the use of augmentation strategies or their combinations may be preferred. For patients who can hardly endure medications or who are refractory, non-drug treatments such as repetitive transcranial magnetic stimulation, transcranial stimulation and electroconvulsive therapy may be adopted. Experimental treatments are also being studied intensively (Gomez, Vance & Gomez, 2014).
How to overcome the disorders
A key challenge in genetic studies of depressive disorders remains the precise characterization of the phenotype. However, even with variations in the concept of depression, it can be concluded from a large number of investigations. For instance, studies with families, twins and adopted children indicate that there is a genetic component to both unipolar and bipolar depression. It is estimated that this genetic component represents about 40% of the susceptibility to develop unipolar depressive disorder and 70% for bipolar disorder. The genetic transmission mode remains undefined, although independent analysis already suggests that depression is most likely multi-factorial. Moreover, molecular genetic studies have failed to identify a specific gene locus for depressive disorders possibly because it is a disease with etiological heterogeneity. The neurochemical and neuroimaging studies combined with the identification of disease susceptibility genes and research on the interaction between the brain and the environment continue to be the best strategies in understanding the neurobiology of mood disorders. The latter is not intended to reduce all the pathogenesis of depressive disorders and neuroanatomical changes. Nonetheless, better understanding of pathogenesis may eventually aid in early detection, the development of new treatments, as well as prediction of therapeutic response.
Parenting skills to help the individuals
According to the World Health Organization (WHO), depressive disorders will be the most disabling disease worldwide and the second leading cause of global deaths from disease after heart disease by 2020. These statistics are very worrying since they reflect the scope and social harm of this disease. Individuals who suffer from depressive disorders understand its painful and debilitating nature. Suffering is not confined within those diagnosed with the disorders. Family members and other acquaintances are equally affected. However, what is the role of the family in the diagnosis, management and treatment of depressive disorders?
The family unit in society is fundamental. Patients find support and comfort through the family. First, the most important aspect is to ensure that the person suffering from a depressive disorder is treated with a family psychiatrist in order to enhance the trust level of patient. Second, patience is vital. Quite often, living with depressed person is very difficult. Hence, family members should exercise patience all the time. Family members should also understand that any depressive disorder is an illness. Therefore, psychiatric treatment is very important. Family members should also learn to listen regardless of the severity of the situation. It is prudent to pay attention to the depressed person. In addition, it is pertinent to respect the schedule of the patient in order to manage time well.
Members of a family should also follow the treatment process and always be in touch with the physician in charge. They should ensure that the patient is adhering to treatment.
Evidence-based therapies for specific disorder
Depressive disorders are among the most prevalent psychiatric disorder during lifetime. The average age is around 27 years according to some statistics. One of the best evidence-based practice in the management of Major Depressive Disorder is psychotherapy. Individuals who are depressed are given the opportunity to openly discuss their experiences and coping strategies. Hence, it is the duty of trained professionals to create a dialogue environment with patients. In fact, patients diagnosed with Major Depressive Disorder need people to listen to them as part of lowering stress level.
Recently, the use of magnetic stimulation has been approved in the treatment of depressive disorders. It is an innovative technique with an efficiency level of about 60 to 70% in spite of a number of mild side effects. The latter makes this technique a great tool in the treatment of depressive disorders (Boschloo et al., 2013).
From the above analysis, it is evident that depressive disorders are still a major public health concern. These disorders are not determined by the age of an individual as erroneously depicted in some past studies. While the diagnosis of major depressive disorders has been carried out successfully, treatment and management of the conditions are glaring challenges that are yet to be tackled. Needless to say, family members can play momentous roles in assisting close relations to manage quite a number of depressive disorders.
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