Bipolar affective disorder cause

The sequence, number, and intensity of manic and depressive episodes are highly variable. The cause of the mood swings characteristic of bipolar affective disorder is unknown, although a preponderance of catecholamine-related activity may be present. Drugs that increase this activity tend to exacerbate mania, whereas those that reduce activity of dopamine or norepinephrine relieve mania. Acetylcholine or glutamate may also be involved. The nature of the abrupt switch from mania to depression experienced by some patients is uncertain. Bipolar disorder has a strong familial component, and there is abundant evidence that bipolar disorder is genetically determined. 

The risk of mental complications seems to increase substantially if doses of 200 mg or more are given (11). Amantadine can cause mania and is contraindicated in patients with bipolar affective disorder (12). 

Lithium salts are ineffective for prophylaxis of bipolar affective disorder in around 35% of patients and cause several unwanted effects. The search for alternatives has produced drugs that are more familiar as anticonvulsants, notably carbamazepine and sodium valproate, and possibly lamotrigine. 

There may be abnormalities in eiythrocyte membrane transport properties in patients with bipolar affective disorders, though the interpretation is confounded by the uncertainty with regard to the contribution of hypertension in patients who are coincidentally hypertensive and manic depressive. The administration of lithium also may cause adaptive change (93,117,135-137). This results in an increase in erythrocyte lithium concentrations after prolonged lithium therapy, which could be mediated either by increased flux into the cell or via reduction in efflux rate. An increased content of ankyrins, red cell membrane proteins affecting cytoskeletal structure and functions, has been found in some patients with bipolar affective disorder (138) and this raises further the role of erythrocyte membrane defects in the etiology of the disease. 

A patient suffering from bipolar affective disorder (BAD) becomes pregnant. A drug that has been shown to have some clinical value in alleviating BAD symptoms and that is unlikely to cause problems regarding fetal development is... 

Several antiseizure drugs have some effectiveness in bipolar affective disorder. Of the dmgs listed, clonazepam does not appear to cause teratogenic effects and would be the safest during pregnancy. The answer is (B). 

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. 

Numerous reports of altered neurotransmitter and hormone functions which have been associated with the affective disorders are reviewed by Levell [142]. It was originally proposed that one or more of the neurotransmitter amines in the brain (norepinephrine, dopamine, serotonin) may be functionally elevated in manic patients and reduced in depressed patients [143]. For instance, an increase in the production of dopamine, observed in a number of case reports, is thought to be the cause of the switch into the manic phase in bipolar patients. For example, Bunney et al. reported an increase in the level of homovanillic acid (HVA), a... 

Glueck et al. assessed hypocholesterolemia in 203 patients hospitalized with affective disorders (depression, bipolar disorder, and schizoaffective disorder), 1595 self-referred subjects in an urban supermarket screening, and 11,864 subjects in the National Health and Nutrition Examination Survey II (a national probability sample) [34], Low plasma cholesterol concentration (<160 mg/dL) was much more common in patients with affective disorders than in those found in urban supermarket screening subjects or in the National Health and Nutrition Examination Survey II subjects. When paired with supermarket screening subjects by age and sex, patients with affective disorders had much lower TC, LDL, HDL, and higher TG concentrations. However, there was no evidence that low plasma cholesterol could cause or worsen affective disorders [34]. 

Depression is a common condition with both psychologic and physical manifestations. The three major types of depression are (1) reactive depression, a response to external events (2) bipolar affective (manic-depressive) disorder, described in Chapter 29 and (3) major depressive disorder, or endogenous depression, a depression of mood without any obvious medical or situational causes. The drugs used in major depressive disorder are the subject of this chapter. 

Bipolar disorder usually begins in early adulthood and affects approximately 1% of the population. The cause of the disorder is largely unknown although hereditary factors play an important part, and major life events often precede the onset of the first episode of the disorder, and less obviously subsequent episodes. 

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). 

An effective treatment for bipolar disorder (manic -depressive illness) is the administration of lithium salts 445/1111-11133 Inhibition of the hydrolysis of inositol phosphate by Li+ (Fig. 11-9) may be related to its therapeutic effect. Reduced phosphatidylinositol turnover may dampen responses to neurotransmitters.1114 Li+ may affect gene expression in neuropeptide-secreting neurons.1115 Bipolar disorder apparently has more than one cause. There are strong indications of genetic susceptibility,1116 and genes that increase susceptibility have been located on chromosomes 4,12,13,18,21, and X.1117... 

First, atypical antipsychotics undoubtedly cause far fewer EPS than do conventional antipsychotics and often cause essentially no EPS (i.e., they really do perform in this respect, as predicted pharmacologically and as advertised). Second, atypical antipsychotics reduce negative symptoms of schizophrenia better than do conventional antipsychotics, but this may be because they do not make things worse as much as because they really reduce negative symptoms. The magnitude of this effect is not as robust as the effects on EPS, and further innovations will be necessary to solve the negative symptom problem in schizophrenia—nevertheless, this is a good start. Third, atypical antipsychotics reduce affective symptoms in schizophrenia and related disorders such as treatment-resistant depression and in bipolar disorder, where treatment effects appear to be quite robust. Fourth, atypical antipsychotics may... 

In a retrospective chart review of 167 patients with a variety of anxiety disorders, excluding patients with evidence of current or previous mood disorder, manic episodes were recorded in five patients, a rate of 3% (20). While this might suggest a clear effect of SSRIs to induce mania, two of the patients were taking clomipramine, a tricyclic antidepressant, albeit a potent serotonin reuptake inhibitor. In addition, all the affected patients had additional diagnoses of histrionic or borderline personality disorder, known to be associated with mood instability. It is still therefore plausible that SSRIs cause mania only in patients with an underlying predisposition, although this may be more subtle than a personal or family history of bipolar illness. 

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