Major depression refers to a recurrent mental disease or disorder; whose major characteristic is recurrent episodes of reduced mood which lasts a span of at least 14 days. Commonly this is seen as an all-encompassing low mood and poor self esteem. Additionally, this is accompanied by lack of interest in activities which previously brought pleasure to the individual. The condition is serious and is commonly accompanied by adverse effects on the various aspects of an individual’s life including family, work or school.
Additionally, the condition may also lead to physical effects including sleep disorders, changes in eating habits; and may eventually lead to suicide. In fact, in the United States, it is estimated that 3.4% of patients diagnosed with major depression commit suicide and 60% of all suicides involve person who have been diagnosed with depression.
The diagnosis of major depression is based on self-report, observation by close family members and friends; and mental status exam. Additionally, the attending physician may be inclined to have some physical tests to evaluate physical morbidity caused by depression; or to eliminate another etiology of the physical disease. The high risk epidemiological group for diagnosis of depression is people between 25 and 45 years for the first major onset (Kessler et al. 2006); and 50 and 60 years for peak of clinical signs.
Women are twice as likely to develop major depression; however, men commonly show a higher tendency to commit suicide as a result of it. Of the people who experience a major depressive episode, about 75% show recovery within the year with the proper treatment; however, about 60% experience another major depressive episode later in life (Brown &Moran, 1994).
Since the recognition of depression as a legitimate medical disorder, the perception about it has evolved; and several explanations to its occurrence based on psychological, psycho-social, biological, evolutionary and hereditary etiologies. On these bases, various methods and approaches to treatment have arisen; and are commonly used today either independently or in combinations.
Signs and Symptoms of Major Depression
As mentioned before, major depression is a major disease; and any one having it commonly suffers major disruptions of their social, economic and physical wellbeing. The disorder commonly occurs in form of recurrent episodes of very low mood seen in every aspect of the individual’s life; and usually resorts in withdrawal from activities which initially or commonly were pleasurable. During this episode, the person will be preoccupied with thoughts of worthlessness, hopelessness, self-loathing and helplessness (Hays et al. 1995).
Additionally, the person may exhibit a diminished ability to concentrate, poor memory, reduced libido and contemplation of suicide; and sleep disorders such as insomnia or rarely, hypersomnia. Major depression also commonly results in disorders of eating; resulting in physical changes of the individual. Such include more commonly loss of weight or more rarely gain of weight.
Depressed patients also exhibit physical signs of the condition; these include fatigue, headaches and disorders of bowel movements and the gastrointestinal tract. Physical complaints are the primary presenting sign in developing countries; accompanied by changes in behavior reported by the person’s next of kin.
As mentioned before, the peak period for depression is in people between 50 and 60 years. In older people, depression is commonly accompanied by forgetfulness and lethargy. Additionally, in the older age group, depression is commonly accompanied by other physical disorders such as heart disease, Type-II diabetes and Parkinson’s disease (Yohannes & Baldwin, 2008). On the other hand, depression in children may be seen as irritability rather than low moods.
Signs which may lead a parent to suspect that the child may be depressed include loss of interest in school and subsequent poor grades; demanding or clingy behavior; or insecure. In case of adolescence, depression may be misconstrued as the normal low moods associated with this age group thus delaying diagnosis and treatment. Additionally, depression may be accompanied by attention-deficit hyperactivity disorder thus hampering correct diagnosis and complicating treatment (Brunsvold et al. 2008).
The severity of depression on a population level varies based on age, gender, socioeconomic-status, racial and ethnic bases. Severe major depression is seen as psychoses such as delusions and/or hallucinations; some of which could be terrifying; the latter status is rarer.
Risk Factors of Major Depression
As mentioned before, on a population level, the risk of development of major depression is not uniformly distributed; and some segments carry a bigger risk of developing the condition than others. A good example is the examination of the American population which is almost unrivalled in terms of ethnic, racial and cultural diversity. In this case, some schools of thought are of the opinion that the African American population has a higher likelihood of developing depression than the white population in the country (Somervell et al. 1989; Neighbors et al. 1983; Warheit et al. 1975).
Other scholars are of the opinion that there is no significant difference between the prevalence of major depression among white and black populations in the US (Kessler et al. 1994; Blazer et al. 1994; Kessler et al. 2003; Weissman et al. 1991). However, it is prudent to note that few studies have dedicated themselves to delve into the comparison between the various ethnic and racial groups in regards to the occurrence of major depression.
One study however, titled ‘Prevalence of Depression by Race/Ethnicity: Findings from the National Health and Nutrition Examination Survey III’ (Riolo et al, 2005) suggested that the real difference can be seen if the type of depression is taken into consideration during the comparison. For example, African American and Mexican American population showed a higher tendency of developing dysthymic disorders; on the other hand, white American segments of the population had a higher tendency of developing major depressive disorders (Riolo et al, 2005).
Socioeconomic Status and Cultural Factors
The socioeconomic and cultural factors can put a certain segment of the population at a relatively higher risk of developing a mental condition than others. For example, from the above study, farina Americans and Mexican Americans were found to carry a higher risk of chronic dysphoria precipitated by poverty and lack of education. Even within a relatively homogenous cultural or ethnic group, certain individuals have been shown to be at a higher risk of depression than others; for example, Mexican immigrants with poor mastery of the English language; and without generational companionship have been shown to have a relatively higher prevalence of dysthymic disorders (Hovey & King, 1996).
The methods used to diagnose depression in white population cannot be transferable directly to non-English speaking individuals; even with the translation of the self-assessment instruments into Spanish; as such a good amount of crucial data always runs the risk of being lost in translation; making such studies relatively inaccurate.
Another factor which may, according to the study, have put African American and Mexican American segments of the population at higher risk of major depression is the difference in seeking and accessing mental health services; and subsequent prescription and use of psychotropic medication (Riolo et al. 2003a). As such, although these two groups showed lower levels of major depression than their white contemporaries, they are also less likely to receive either a diagnosis or treatment for mental disorder; and thus were at a higher risk of developing chronic or severe depression (Riolo et al. 2003a; Riolo et al. 2003b).
The socio and cultural aspects of any one community can offer limitless combinations of situations which may lead an individual down the path of depression; considering the sheer diversity of the American population, a complete study of the presence and causes of differences in the prevalence of depression may actually be never achieved. Additionally, the heavy dependence on self-report when carrying out cross-cultural studies robs the investigator the privilege of examining non-verbal signs of depression. Future studies into this factor should also seek to add more measurement parameters such as comorbid disorders for instance chemical dependency; and rural/urban residence.
In today’s world, a large proportion of the population spends the large part of the waking hours at the workplace; and this is a prime place for an individual to develop depression. Indeed, factors at work may not practically be the primary cause of depression in an individual; however, in people who are already susceptible, psychosocial factors at work may be just the thing that pushes that person over the edge and into psychiatric morbidity. Indeed, some countries have shown alarming prevalence of depression; for example, the American workforce showed a 6.4% occurrence of major depressive disorders within a 12 months period based on the World Health Organization (WHO) Composite Diagnostic Interview (CDI) (Kessler et al. 2006).
On the other hand, the workforce in Denmark, the prevalence for major depression was pegged at 3.3% based on the Major Depressive Inventory (MDI) which is a self-administered instrument (Olsen et al. 2004).
Literature has in the past strongly linked stress occurrence of major depression with constant exposure to stressful event during life; with the risk being higher with the intensity and contextual importance of such events (Kessler 1997). As mentioned before, about 60% of all the cases (of depression) are followed by other episodes later in life; even with complete recovery from the first one. Literature has identified that life events are more important in the development of the very first episode of severe depression than in the subsequent episodes (Mitchell et al. 2003). Despite this strong link between severe life events, it is important to consider whether chronic difficulties can cause depression through the same mechanisms (Kessler, 1997).
Psychosocial stressors at work fall into the category of chronic difficulties; these are important for two reasons. First, such stressors are easily to prevent and/or control simply by changing aspects in the work environment causing the stress in the first place; the same cannot be said of severe life events which are mostly unexpected and unavoidable. Secondly, being exposed to a stressful situation for extended periods of time many lead to more severe episodes of major depression; and may hamper the recovery of an individual who is not removed from such an environment during and after the period of treatment (Tennant, 2001).
A clear link has been established between psychosocial factors at work and psychological disorders; and depression in particular (Tennant 2002; Kessler 1997; Mitchell et al. 2003). The impact of these stressors and clinical psychiatric disorders in the workplace has not been sufficiently documented; this is a less than ideal situation considering that depression can result in long-term physical and psychological disability and dependency; and affects productivity at the workplace due to sick leave, morbidity and mortality (Prince, 2007).
In a workplace setup, various factors either working in isolation or in combination can contribute to the occurrence of a major depression episode. Some of these factors include mental load, monotony of the tasks, hectic environment; social structures and support within the organization (for example same age groups, socioeconomic, ethic or racial counterparts); job overload or difficulty; poor evaluation of an individuals contributions at the workplace; work related violence and/or threats (for example for illegal migrant workers); unreliable job security, lack of control, lack of relevant qualifications and/or experience; procedural injustice, excess commitment or obsession, support and relations with superiors and supervisors, skill discretion among others.
Indeed, even in a situation whereby everyone is exposed to the same environment, not everyone will succumb to the stresses with a major depressive episode. The risk factors of an individual will always determine whether stress will culminate in depression or not; such well documented factors include the age, gender, income levels and marital status. Additionally, the exposure of the individual to severe and intense life events outside the work environment such as marital separation, premature death (of a loved one or a family member); personal traits and behaviors, family history of depressive disorders and physical health can be important factors in determining whether a major depressive disorder will develop or not.
As mentioned before, major depressive disorder is a recurrent disease; as such about 60% of the patients who have experienced one major depression episodes experience another episode within their lifetime. As such, a person with a history of depression (unrelated to the work they are doing now) has a higher likelihood of developing depression in case of a stressful work environment. In the face of such many variables in the determination of the risk factors of depression, it is often difficult to take measures to prevent it in a workplace. For example, refusing to employ someone who has had a history of depression may be perceived as discrimination based on mental health prejudice.
Alcoholism and Major Depression
Depression and alcoholism have been shown to have an inseparable link; indeed, depression is the disorder most frequently diagnosed in alcoholic patients; whereby 27-69% shows high depression scores; and approximately 15-28% suffers from an episode of major depression (Uekermann et al, 1998). The link between depression and alcoholism has not been fully described; however, strong relationships have been shown between the neuropsychological pathways of development of the two conditions; with the occurrence of one precipitating the development of the other.
Researchers have also tried to link alcoholism and depression to genetic factors; studies have identified a genetic variant of alcoholism to depression thus linking these two conditions. Already, studies had shown that 30 to 70% of the alcoholics suffered from depression and anxiety. The relationship is linked to a gene known as the CREB gene (because it codes for the production of a protein known as CREB-cyclic AMP). The activity of this gene in a section of the brain known as the Central amygdala has been shown to affect how a consumption of alcohol and depression are related [Li et al 2004].
The lack of the CREB gene determines how one responds to stressful situations and is implicated for driving this response towards alcohol consumption. In studies carried out on rats, the candidates that did not have an active CREB gene were shown to drink 50% more alcohol than those with the gene [Li et al 2004]. This in comparison to the intake of water; the rats were also tested for the intake of sugar water of which they had equal preference thus eliminating the issue of taste preference from play. When exposed to stressful situations, the ‘alcoholic’ rats tended to drink more alcohol than the other rats which resulted in reduced anxiety; however, the alcohols effects of reducing depression and anxiety were not as great as on the normal rats [Li et al 2004].
Another plausible explanation is the need on the part of the patient to dull the symptoms through self-medication with alcohol; this is more likely to take place in an environment where alcohol is widely accepted as a means of coping with stressful situations; such as in alcoholic families (McMiller & Plant, 1996). In addition to this, certain recreational drugs have been shown to precipitate depression in a mechanism similar to that seen in alcohol abuse. The major depressive episodes in this case can occur during the period of use or that of withdrawal; for example during drug rehabilitation therapy.
Epidemiology of Depression
The above-described risk factors are not conclusive; indeed, a lot of work is going on to try to separate and identify the role that each plays in the causation of depression in individuals. One thing however which consensus has been found is that depression is a major cause of psychiatric and physical disease in the world (WHO, 2001). The lifetime prevalence of the condition however varies widely from country to country; with a country such as Japan having 3% and the United States showing 17%. Most other countries fall within this range; many of them showing lifetime prevalence between 8 and 12% (Andrade et al. 2003; Kessler et al. 2003). As mentioned before, gender is an important issue in depression with females showing twice as much probability of developing major depression than males.
In developed countries, particularly in North America, a new high-risk epidemiological group is emerging; the adolescents. There has been a steady increase in the prevalence of adolescent depression; this has been attributed to psychosocial factors rather than hormonal changes associated with this period of development. Studies have revealed alarming prevalence of depression among teenagers in certain communities. One study showed a prevalence of 4.7% among youth aged between 14 and 16 years of major depressive disorders. This was in addition to a 3.3% prevalence of dysthymic disorders (chronic minor depression) (Kashani et al, 1987).
Depression is a condition that is more likely to be missed in teenagers than in other groups; this also put them at a bigger risk of developing alcoholism and drug abuse; or degenerating into severe and potentially irreversible mental ill health since the condition may easily go undiagnosed and untreated. This diagnosis is also made more difficult by the discomfort teenagers usually feel in discussing their intimate issues even with doctors. This secrecy can be attributed to various issues including a fear of being revealed to their parents and/or teachers; or being ostracized from the social groups.
Apart from this, depression is currently the leading cause of morbidity in North America and other industrialized countries; worldwide, the condition is ranked fourth. More alarmingly, however, is the fact that this situation is worsening; the World Health Organization (WHO) predicted that by the year 2030, major depression will be the second leading cause of morbidity in the world, beaten only by HIV infections and AIDS (Mathers & Loncar, 2006). In addition to this, depression is often accompanied by unemployment and poverty due to its disabling characteristics.
The fact that the prevalence of depression and its effects in the world is increasing has been attributed to two major factors. One of them is a failure to acknowledge the recurrent nature of the condition; and therefore a failure to seek medical attention for recurrent episodes of depression. The other factor is the failure or the inability of the medical services sector to provide comprehensive and effective treatment for depression patients; commonly resulting in relapses and reoccurrences of depression episodes (Andrews, 2008).
Among the more negative aspects of depression is the social stigma attached to it; and thus lack of a standard way of classifying it. Even today depression is still referred to as ‘disease ’, ‘disorder’ or ‘state of mind’ without any of these terms being selected as the official one. This has gravely affected the way that depressed individuals are treated by the society; and may even play a part in worsening the situation for some people. The bottom line however is that depression is a serious, urgent, growing and global problem which needs to be tackled before things get out of hand.
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