Unipolar depression disorders

Bauer M et al. (2002). World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of unipolar depressive disorders. Part 1 Acute and continuation treatment of major depressive disorder. World Journal of Biological Psychiatry, 3, 5-43. 

The mood disorders were once called affective disorders and are grouped into two main categories unipolar and bipolar. The unipolar depressive disorders include major depressive disorder and dysthymic disorder the bipolar disorders include bipolar 1, bipolar II, bipolar not otherwise specified, and cyclothymic disorder. Other mood disorders are substance-induced mood disorders and mood disorders due to a general medical condition. In addition, mood disturbance commonly occurs as a symptom in other psychiatric disorders including dementia, post-traumatic stress disorder, substance abuse disorders, and schizophrenia. 

Clarke, G.N., Hawkins, W, Murphy, M., Sheerer, L.B., Lewiston, P.M., and Seeley, J.R. (1995) Targeted prevention of unipolar depressive disorder in an at-risk sample of high school adolescents a randomized trial of a group cognitive intervention. / Am Acad Child Adolesc Psychiatry 34 312-321. 

Lithium has been proven effective for acute and prophylactic treatment of both manic and depressive episodes in patients with bipolar illness (American Psychiatric Association 2002). However, patients with rapid-cycling bipolar disorder (i.e., patients who experience four or more mood disorder episodes per year) have been reported to respond less well to lithium treatment (Dunner and Fieve 1974 Prien et al. 1984 Wehr et al. 1988). Lithium is also effective in preventing future depressive episodes in patients with recurrent unipolar depressive disorder (American Psychiatric Association 2002) and as an adjunct to antidepressant therapy in depressed patients whose illness is partially refractory to treatment with antidepressants alone (discussed in Chapter 2). Furthermore, hthium may be useful in maintaining remission of depressive disorders after electroconvulsive therapy (Coppen et al. 1981 Sackeim et al. 2001). Lithium also has been used effectively in some cases of aggression and behavioral dyscontrol. 

I Lithium is also used in the prophylaxis of recurrent unipolar depressive disorder. I Controlled trials suggest response rates of 30-40%, and while the strategy is significantly more efficacious than placebo, the magnitude of effect is small. 

In addition, it exerts beneficial effects in many disorders as an adjuvant to other treatment modalities. Such effects are apparent only if it is administered to an already pharmacologically treated patient. For example, in unresponsive major depressive disorder, the co-administration of lithium to an ongoing antidepressant treatment increases the response rate by up to 50%. In most cases, the response to lithium augmentation is either considerable or not at all ( all-or-none phenomenon). Some (currently not convincing) results have also been reported in unipolar depression, bulimia nervosa, and attention deficit hyperactivity disorder (ADHD). Lithium also exerts antiaggressive effects in conduct disorder, independent of any mood disorder, and can reduce behavioral dyscontrol and self-mutilation in mentally retarded patients. One of the most striking effects of lithium is its antisuicidal effect in patients who suffer from bipolar and unipolar depressive disorder irrespective of comorbid axis I disorder. ... 

Bauer M, Whybrow PC, Angst J et al. World Federation of Societies for Biological Psychiatry (WFSBP). Guidelines for biological treatment of unipolar depressive disorder. Part 2. World J Biol Psychiatry 2002 3 69-86. 

Ikemi, Y. and S. Nakagawa, A Psychosomatic Study of Contagious Dermatitis , Kyoshu Journal of Medical Science 13 (1962) 335-50 Imel, Zac E., Melanie B. Malterer, Kevin M. McKay and Bruce E. Wampold, A Meta-Analysis of Psychotherapy and Medication in Unipolar Depression and Dysthymia , Journal of Affective Disorders no (2008) 197-206... 

These data show that for three psychotic disorders (schizophrenia, bipolar disorder and unipolar depression) the genetic contribution is over 50% but for reactive depression (in response to a traumatic life event ) and tuberculosis, an infectious disease caused by a species of Mycobacterium, environmental factors account for over 90% of the variance. 

Turning to the pharmacotherapy for mania, for decades lithium was the only effective drug treatment. More recently, a number of antiepileptic drugs including carba maze pine, lamotrigine and valproate have been shown to also act as mood stabilisers and are becoming established for the treatment and prophylaxis of both unipolar mania and bipolar manic depressive disorders. 

In clinical psychiatric terms, the affective disorders can be subdivided into unipolar and bipolar disorders. Unipolar depression is also known as psychotic depression, endogenous depression, idiopathic depression and major depressive disorder. Bipolar disorder is now recognised as being heterogeneous bipolar disorder I is equivalent to classical manic depressive psychosis, or manic depression, while bipolar disorder II is depression with hypomania (Dean, 2002). Unipolar mania is where periods of mania alternate with periods of more normal moods. Seasonal affective disorder (SAD) refers to depression with its onset most commonly in winter, followed by a gradual remission in spring. Some milder forms of severe depression, often those with an identifiable cause, may be referred to as reactive or neurotic depression. Secondary depression is associated with other illnesses, such as neuro-degenerative or cardiovascular diseases, and is relatively common. 

Mood stabilisers are used to regulate the cyclical change in mood characteristic of bipolar disorder, since they can attenuate both manic and depressive phases. Their main use is as a prophylactic for manic depression and unipolar mania. However, they can also be administered concomitantly with antidepressants for refractory (non-responsive) unipolar depression. 

Antidepressant A drug used principally to treat major depressive disorder (unipolar depression). 

The unipolar mood disorders consist solely of episodes of depression. On the other hand, the bipolar mood disorders consist of episodes of both depressed and elevated mood. The periods of elevated mood are characterized by either euphoria or irritability and are called mania or hypomania depending on the level of severity. A schematic of the mood disorders is shown in Figure 3.1. Substance-induced mood disorders and mood disorders due to general medical conditions usually manifest depressed mood however, manic episodes are occasionally seen as well. 

In addition to epilepsy, reduced GABA has been recorded in patients with unipolar depression, following alcohol withdrawal and in hepatic encephalopathy. The finding that the concentration of GABA is reduced in depression is unexpected as there is no evidence that the disorder is associated with an increased cortical excitability. One possibility is that the reduction in GABA is a reflection of a decreased availability in its excitatory amino acid precursor glutamate. 

Manic-depressive illness connotes a psychotic disorder of affect that occurs episodically without external cause. In endogenous depression (melancholia), mood is persistently low. Mania refers to the opposite condition (p. 234). Patients may oscillate between these two extremes with interludes of normal mood. Depending on the type of disorder, mood swings may alternate between the two directions (bipolar depression, cyclothymia) or occur in only one direction (unipolar depression). 

The most common mood disorders are major depression (unipolar depression) and manic-depressive illness (bipolar disorder). Major depression is a common disorder that continues to result in considerable morbidity and mortality despite major advances in treatment. Approximately 1 in 10 Americans will be depressed during their lifetime. Of the 40,000 suicides occurring in the United States each year, 70% can be accounted for by depression. Antidepressants are now the mainstay of treatment for this potentially lethal disorder, with patients showing some response to treatment 65 to 80% of the time. 

In this chapter we review extant data on the neurobiology of unipolar and bipolar depressive disorders in children and adolescents. A complement to two recent reviews (Kaufman and Ryan, 1999 Kaufman et ah, 2001), this chapter places primary emphasis on those studies in which neuroimaging techniques have been used. Unfortunately, such studies are few and far between. Preclinical models that have guided research on the neurobiology of affective disorders in adults are discussed, and, given the limits in the application of these models to juvenile samples, especially in the case of unipolar disorder, the need for more developmentally focused preclinical work is emphasized. 

Unipolar and bipolar depressive disorders in children and adolescents are serious conditions. The pathophysiology of these disorders is poorly understood. The new tools available through neuroimaging techniques will help to unravel the neuroanatomical systems involved in the onset and recurrence of these disorders. There is a need for more developmentally informed predinical research and more studies of the normal development of the neural systems implicated in emotional regulation. 

There is no empirical evidence available for clinical use in children and adolescents. Yet, Hypericum seems to be used for the treatment of mild to moderate depression in the young (Walter et ah, 2000). St. John s wort should be avoided in young patients with severe depression and bipolar disorder (given the lack of adult data about effectiveness and risk of manic induction, respectively) and in those who have significant suicide risk. Treatments of proven efficacy (e.g., SSRIs, mood stabilisers) should be preferred in these cases. However, St. John s wort may be considered in cases of unipolar depression where conventional treatments have failed and prior to the use of combinations of drugs that have an increased risk of side effects and whose efficacy has not been demonstrated. 

Offspring of parents with bipolar disorder have an almost three fold increased risk for developing a mental disorder, and a fourfold risk for an affective disorder, as compared to the offspring of parents with no mental disorder (LaPalme et ah, 1997). Families of patients with early-onset bipolar disorder have higher than expected rates of substance abuse, unipolar depression, antisocial personality, and comorbid bipolar disorder with ADHD. Biederman et al. (2000) have concluded that this comorbid bipolar plus ADHD condition is familial, as evidenced by the fact that the two conditions... 

The treatment of the major depressive disorders such as unipolar and bipolar depressions was initially considered to be uniform, ffowever, with psychopharmacological advances, it has been demonstrated that the patients with bipolar depression may be partially responsive, at least prophylactically responsive, to lithium therapy, whereas the patients with unipolar depression are not as responsive (Abou-Saleh 1992). In addition, the treatment of depression may contribute through serendipity to the confirmation of a subgroup of patients with a bipolar disorder referred to as bipolar II. These patients, following treatment with antidepressants, will switch over to a hypomanic or fully manic phase resulting from pharmacological mechanisms. Thus, another subgroup of the bipolar disorder may be identified in the future. 

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