Primary early onset dysthymia, biochemical correlates of the therapeutic response to fluoxetine: I. Platelet monoamine oxidase and the dexamethasone suppression test

O papel dos glicocorticóides na expressão dos sintomas de humor: uma revisão

O objetivo desta revisão é verificar, na literatura, uma relação entre níveis plasmáticos aumentados de corticosteróides e sintomas psiquiátricos, identificar as manifestações clínicas mais comuns e os tratamentos propostos. Alterações no eixo hipotálamo-hipófise-supra-renal levando a hipercortisolemia estariam associadas a distúrbios do humor, sobretudo depressão, enquanto que o uso de drogas glicocorticóides estaria relacionado ao aparecimento de sintomas psiquiátricos, como mania, depressão, labilidade afetiva e psicose. O levantamento bibliográfico foi realizado através dos indexadores Medline e Bireme no período de 1993 a 2003, em inglês, francês e espanhol, utilizando-se o cruzamento das seguintes palavras-chave: cortisol, corticosteróides, depressão, transtorno bipolar e psicose. Foram incluídos artigos originais (33) e de revisão (22) e excluídos relatos de caso. Alguns estudos sugerem que altas concentrações plasmáticas de cortisol, em longo prazo, podem levar à depressão, propondo que a utilização de drogas antiglicocorticóides teria efeito antidepressivo. Outros estudos, por outro lado, indicam não haver associação entre hipercortisolemia e episódios depressivos.

Dysthymia: a review of pharmacological and behavioral factors

Although dysthymia, a chronic, low-grade form of depression, has a morbidity rate as high as that of major depression, and increases the risk for major depressive disorder, limited information is available concerning the etiology of this illness. In the present report we review literature concerning the biological and characterological features of dysthymia, the effectiveness of antidepressant treatments, the influence of stressors in the precipitation and maintenance of the disorder, and both quality of life and psychosocial correlates of the illness. We also provisionally suggest that dysthymia may stem from disturbances of neuroendocrine and neurotransmitter functioning (eg, corticotropin releasing hormone and arginine vasopressin within the hypothalamus, or alternatively monoamine variations within several extrahypothalamic sites), and may also involve cytokine activation. The central disturbances may reflect phenotypic variations of neuroendocrine processes or sensitization of such mechanisms. It is suggested that chronic stressor experiences or stressors encountered early in life lead to the phenotypic neurochemical alterations, which then favor the development of the dysthymic state. Owing to the persistence of the neurochemical disturbances, vulnerability to double depression is increased, and in this instance treatment with antidepressants may attenuate the symptoms of major depression but not those of the basal dysthymic state. Moreover, the residual features of depression following treatment may be indicative of underlying neurochemical disturbances, and may also serve to increase the probability of illness recurrence or relapse.

Platelet MAO activity in patients with dysthymic disorder

The aim of the present study was to examine possible associations between platelet monoamine oxidase (MAO) activity and primary dysthymic disorder. For that purpose we estimated the enzyme activity in 58 patients (15 males and 43 females) selected according to DSM-III-R criteria and in 61 healthy controls (30 males and 31 females). Platelet MAO activities were found significantly lower in the female patients compared to female controls. Moreover, the enzyme activities were found to be even lower in the female patients who had attempted suicide. These differences did not exist in the male population. We could not find any associations of MAO activity to the age of the patients, the age of onset, the duration of dysthymia, or HAM-D and SCL-90R scores. Our findings are consistent with the hypothesis that platelet MAO activity is a trait-dependent indicator of vulnerability to dysthymic disorder and suicidality in our female population.

The dexamethasone suppression test and treatment outcome in elderly depressed patients participating in a placebo-controlled multicenter trial involving moclobemide and nortriptyline

The dexamethasone suppression test (DST) was conducted in 95 elderly DSM-III-R depressed patients randomized for treatment with moclobemide (MOC; 400 mg daily), nortriptyline (NT; 75 mg daily), or placebo (PBO) in a 7-week double-blind multicenter study. Patients were assessed weekly using various clinical scales, including the 17-item Hamilton Depression Rating Scale. The DST was administered at baseline and at the end of treatment. At baseline, no relationship was found between DST status and the various clinical scales used. At the end of treatment, suppressors (DST-) had significantly improved clinical ratings compared to nonsuppressors (DST+), and were mostly found among those treated with NT (71%) as compared to MOC (41%) or PBO (33%) (p < .03). On the other hand, baseline DST measures influenced treatment outcome; DST+ patients had a greater number of treatment responders to NT (48%) than MOC (19%) or PBO (20%) (p < .07). For DST- patients, the situation was reversed: NT, 7%; MOC, 31%. Postdexamethasone cortisol levels were lower in MOC responders (p < .07). An interaction was found between DST and drug-specific response. The DST may be a useful adjunct for predicting and evaluating the outcome of antidepressant therapy.

Major depression, minor depression, and double depression: are they distinct clinical entities?

The clinical concept of "double depression," i.e., the superimposition of a major depressive disorder in a patient with dysthymic disorder, implies that there are at least some differences between dysthymia, major depression, and double depression. However, the relationship between these two syndromes remains unclear. The present study uses genetic methodology to explore any possible relationship between minor depression, double depression, and major depression. From 1988-1990, all consecutive unrelated inpatients and outpatients (index cases) presenting to a university-based mood disorders service had detailed family histories taken, using modification of the "family history method." Diagnoses for index cases and their first-degree relatives were made according to Research Diagnostic Criteria. For all index cases with a diagnosis of minor or intermittent depression, and minor/intermittent depression plus either single or recurrent depression ("double depression"), morbidity risks for mood disorders were calculated for first-degree relatives (parents, siblings, and children) using the maximum likelihood approach. Results showed no significant differences in morbidity risk calculations to first-degree relatives of index cases with minor/intermittent depression, major depression, or double depression. The data from this genetic perspective suggest that single depression, recurrent depression, minor depression, and double depression are indistinguishable.

Pharmacological therapy of dysthymia

For a number of years, dysthymia was considered to be non-responsive to antidepressant treatment. During the last decade, early studies with tricyclic antidepressants (TCAs) demonstrated the superiority of the TCAs over placebo. The side effect profile of the TCAs and the moderate degree of symptomatology resulted in reduced compliance and thus to the clinical impression of lack of efficacy. The newest generation of antidepressants, the SRRIs and the RIMAs, with their more acceptable side effect profiles, allowed for the adequate evaluation of pharmacotherapy in dysthymia. The initial open studies with SSRIs indicate a clear efficacy of this group of antidepressants. Likewise, a 5HT2 antagonist, ritanserin, has been shown to be superior to placebo. More recently, a large placebo-controlled study of moclobemide, a RIMA, clearly demonstrated the superiority of this drug over placebo. Based on this evidence, it is now appropriate to consider antidepressants as a clearly effective method of treating dysthymia.