Depression: DSM criteria, cognitive-behavioral and biochemical perspectives

Depression Disorder

Psychology-Disorders

This paper is about depression. It will cover the DSM diagnostic criteria, and discuss the development of depression from two viewpoints, CBT (cognitive-behavioral therapy) and the biochemical and environmental components which are linked causative factors. This paper will then cover the four key indicators of depression, including physical, cognitive, social and emotional symptoms.

Description of depression

DSM-IV criteria

Depression is typified by a number of key diagnostic factors. One can differentiate between generalized depression and major depressive episodes. In order to be diagnosed as a depressive episode, five of the following elements must be present, according to DSM-IV criteria:

Depressed mood most of the day, and every day.

Reduced sensory interest, including taste, visual, smell.

Significant change in body weight (up or down 5% per month). In children, weight gain is most common.

Insomnia or too much sleep.

Agitation or hyper retardation (of psychomotor skills) every day, observable by others.

Fatigue almost every day

Reduced ability to think or concentrate.

Feelings of low self-worth.

Recurrent thoughts about death (Fleener, 2007)

Depression's various aspects

Depression can be seen from several aspects. These are included in the above DSM criteria, but can be expanded as follows:

Physical: Depression can be both the cause and the effect of physical disabilities. It has been found, for example, that most CHF (Congestive Heart Failure) patients suffer from depression. CHF patients are generally in a downward spiral, in which they eat too much, do not exercise, and withdraw from others, including family (Freedland KE, 2003). Depression can also be a cause of stroke, heart disease and other circulatory ailments (Musselman, 1998).

Cognitive: Contrary to outward signs, depressed patients suffer from brain hyperactivity and stress, which makes it difficult to learn. Depression can lead to reductions in the ability to pay attention, to retain memories, and carrying out tasks (Austin, 2001). Because of this inner turmoil, many depressed people are unable to carry out their daily tasks.

Social: Patients who are depressed tend to withdraw from friends and family. They are unable to communicate effectively because of internal turmoil and a general wish to withdraw from all outside stimuli.

Emotional: Depressed patients tend to be in emotional pain, which includes prolonged sadness, feelings of guilt and poor self-image. As with the above aspects, emotional turmoil can also be a causative factor for depression: moving, divorce and death in the family or of close friends can trigger a major depressive episode or chronic depression.

Nature: Twins Studies Demonstrate Predisposition

Several studies have been performed on twins, including subsets in Denmark, on men only, and in a U.S. community. The special interest of twins' studies is that, to some degree, the impact of genetic factors can be determined independent of environment. Of course, twins many times grow up with one another, which is a factor that can confound the nature vs. nurture result.

Danish study of twins 75 years of age and older revealed that same-sex (although not identical) twins were much more likely to be subject to depression (McGue, 1997). Although not statistically significant, it appears that females were more likely to share depressive traits than men. The correlation is far from perfect: somatic heritability estimates (.31) and affect (.27) demonstrated that only 1/3 to 1/4 of twins were likely to share depression. If Danish twins are comparable to U.S. depression sufferers, which means that they are 4-5 times more likely to suffer depression than their non-twin counterparts. The 406-pair study was well-powered, particularly because age differences were filtered out. The study would have been helped, however, by adding more twins who grew up in separate families (due to adoption, for example).

Nature: Differences between Men and Women

Men and women may suffer from depression for different reasons. While it is well-established that women suffer depression more often than men, the reasons are not well-known (Brommelhoff, 2004). One theory, the "artifact hypothesis," is that women are more likely to seek diagnosis and treatment for depression.

A major Austrian study of 2,662 pairs of twins points to some of the differences between men and women. Whereas women tended to share a genetic predisposition to major depression (36-44%), men's predisposition to depression was only modestly related to "nature." Men who became depressed seemed much more likely to do so due to environmental factors rather than familial or genetic factors.

This Austrian study focused almost exclusively on Major Depressive Disorder, which is a more severe form of depression, using the DSM-IV and DSM-III criteria. This study does not cover specific depressive events. There was little difference, however, in genetic tendencies when three types of depression were analyzed: R major depressive disorder, major depressive disorder, and severe major depressive disorder.

Major contribution: nature or nurture?

Until psychotropic drugs were introduced in the 1950s, there was little that could be done to alter the course of depression. The first generation of drugs, including Lithium and Valium, worked primarily to dull the brain's activity, including the hyperactivity in some segments which caused depression. More recent drugs have targeted serotonin receptors more specifically; this has caused none of the previous patient complaints of feeling removed or dulled, although there have been some complaints of sexual dysfunction and suicide may be increased in teens.

The success of serotonin inhibitors has led to additional research into the biochemical causes of depression. Depression runs through families, which can contribute both environmental and biochemical elements to a patient's depression. Although the biochemical and hormonal causes are not known, it has been demonstrated that depression can run for generations. Perhaps the best way to regard the genetic component which predisposes a person to become depressed, generally with the help of his/her environment or a specific set of stress-producing depressive triggers, such as death, bereavement, loss of employment or other major family problem.

Depression affects about 5% of the U.S. population, and has remained steady since 1970, with the exception of women under 45; in this subset of the population, depression rates have doubled in the past three decades. This increase has been offset by reductions in other population subsets, including younger men, older men and older women (Fleischmann, 2000). This increasing prevalence amongst this group suggests that there is a social component to depression which has changed in those women born in the baby boom. While there may be a biochemical origin in those increases, life stresses could also be a contributor. Specifically, during that period more women below age 45 have entered the workforce, and therefore are balancing the multiple stressors of job and childcare.

Typically, chronic depression is triggered by one or two "major" events, which start the cycle (Fleischmann, 2000) of depression, depressive behavior, and continued or deepened depression. Subsequent chronic depression is a devil's circle, which uses the negative stimuli of withdrawing from social contact, poor health and continued worry to maintain or deepen the depression.

Depression: The Scent of a Woman

There are a number of films which feature depressed leading actors. The author has chosen the Scent of a Woman because the character had real-world reasons for contracting depression (blindness) which may not have been present prior to his becoming visually impaired.

Al Pacino played Colonel Frank Slade, who had planned a wild weekend with his reluctant 'caretaker,' Charlie, who was hired for that period to accompany Slade on his trip (imdb, 1992). Slade's depression is initially caused by his going blind, but exacerbated by his withdrawal from society as none of his senses could be used in a way that he could use them before.

The author uses this example because, although it was never stated that way in the movie, Frank Slade was clinically depressed due to external traumatic events. His plan was to kill himself after his "blowout" weekend. Thus, by DSM-IV criteria, Slade was depressed:

He had thoughts of death.

He had withdrawn from society.

He suffered from hyperactivity, and yet could not sleep.

He suffered as well from sensory deprivation -- or the lack of sensory stimuli.

He had feelings of low self-worth which, in the movie.

Charlie offered a mirror to Slade in a way which allowed him to rationally accept that he was in fact a worthy human being, and that he could pursue sensual experiences despite his handicaps. The movie ends on a triumphal note with Charlie convincing Slade that he should live. One is left to wonder whether it would be so simple for Slade; subsequent events in his therapy should include more positive stimuli (going out and dancing with women, for example) and supplemented by additional social contact. It is in Slade's reaching out to someone that he was ultimately saved.

General prognosis for the disorder

There are no single cures for depression. While many patients receive anti-depressants without further therapy, it is important to access the fundamental causes of depression in order to insure that the psychotropic drugs do not cause a counter-reaction in the patient.

There are as many forms of 'talk' therapy for depression as there are depression-changing drugs. The choice of drug therapy must be determined according to the patient's tolerance for the drug, and dosage must be carefully monitored. Prozac, for example, comes in dosages from 5 mg/day to 80 mg/day.

The likelihood of improvement in depression depends on the age, physical health and stress in a person's life, in addition to the chosen therapies.

Age is a major contributor to depression and the success rate of chosen therapies. A metastudy analyzing 36 primary data articles demonstrated that younger patients (who had had more depressive episodes) were less likely to respond to depression therapy than older patients. This study found, for example, that ECT (Electro Convulsive, or "shock" Therapy) was less effective on younger patients (54%) than older patients (67%), with the threshold at 65 years of age (Mitchell, 2005).

Pharmacotherapy seemed to cause remission in fewer people over 60 years of age than younger. These differences can be partially explained by co-morbidities, as mentioned above. Likewise, older patients are likely to suffer from dementia and diseases which can lead to dementia.

Like many studies, this metastudy failed to address the impact of multiple forms of treatment. As we've seen with mild- to medium-severity depression, CBT plus anti-depression drugs appears to work better than anti-depression drugs alone.

Conclusion

Although the evidence for anti-depression drugs is conclusive in many patient cohorts, there is a substantial amount of work to be done to complete the picture of diagnosis and treatment of depression. Of particular interest is to close the loop between patients with circulatory disease and depression: while it has been demonstrated that patients with Congestive Heart Failure, ACS (acute coronary syndrome, which refers to STEMI and non-STEMI myocardial infarctions) and related diseases are more likely to be depressed, it has not been demonstrated that ameliorating depression improves those patients' medical outcomes; in other words, curing depression may not cure the underlying disease, or even halt its progress (Carney, 2007).

Additional questions need to be answered. Why is it that teens appear to be more likely to commit suicide if they take anti-depressive drugs? Is the effect due to the drugs, or a correlate? And what is the reason why women appear to be more susceptible to depression generally, including genetically-linked depression, while men are more likely to become depressed due to environmental factors?

Psychotropic drugs continue to improve the therapeutic outcome for patients. They have paradoxically raised even more questions about the environmental and biochemical causes of depression. As we learn more about them, we should be in a better position to treat the patients in the future.