[Effect of the location of myocardial infarction on the variability of heart rate: a study during the acute phase]. / Efecto de la localización del infarto de miocardio sobre la variabilidad de la frecuencia cardíaca: estudio en la fase aguda.

OBJECTIVES: The influence of the location of acute myocardial infarction on the autonomic tone and its evolution during the first hours post-infarct has not been fully evaluated. The aim of this study was to analyze this effect using a spectral analysis of the heart rate variability. PATIENTS AND METHODS: Forty-nine consecutive patients with acute myocardial infarction (22 anterior and 27 inferior) in sinus rhythm and free of diseases and drugs which could affect heart rate variability were studied. Five-minute Holter recordings within each hour between 10 and 33 hours after the onset of symptoms were analyzed, calculating the standard deviation of NN intervals and the spectral power of the high and low frequency bands using normalized units. RESULTS: The standard deviation was higher in inferior infarcts (51.4 +/- 23.4 ms vs. 38.6 +/- 14.8 ms in anterior location; p < 0.05) and gradually decreased over time in both locations. The relative distribution of high- and low-frequency bands did not show significant differences related to the infarct location. An inverse significant correlation between the high-frequency component and time was observed for anterior infarcts (r = -0.98; p < 0.001) as well as in the inferior group (r = -0.75; p = 0.04). Conversely, the low-frequency power gradually increased in anterior infarcts (r = 0.98, p < 0.001) while remaining stable in inferior locations (r = -0.08; NS). CONCLUSIONS: A gradual reduction of heart rate variability was observed in patients with acute myocardial infarction during the time of monitorization. The spectral analysis suggests that anterior infarcts present a progressive increase of sympathetic activity and a reduction of vagal tone, whereas inferior infarcts show a parallel reduction in both components of the autonomous nervous system.

[Risperidone in the treatment of chronic schizophrenia: multicenter study comparative to haloperidol]. / Risperidona en el tratamiento de la esquizofrenia crónica: estudio multicéntrico comparativo versus haloperidol.

OBJECTIVE: This study was designed to compare the efficacy and safety of five different doses of risperidone with a fixed dose of haloperidol in patients with chronic schizophrenia. METHOD: After a 1-week single-blind, placebo washout phase, 99 chronic schizophrenic patients were randomly assigned to double-blind treatment with 1, 4, 8, 12 or 16 mg risperidone or 10 mg haloperidol daily for 8 weeks. Efficacy was assessed throughout the study by the Positive and Negative Syndrome Scale (PANSS) for schizophrenia, and Clinical Global Impression (CGI). Safety assessments included the Extrapyramidal Symptom Ratinf Scale (ESRS) UKU Side Effect Rating Scale, vital signs, body weight, ECG and laboratory screening. RESULTS: Risperidone had a bell-shaped dose-response curve, with optimal therapeutic responses occurring at a daily dose of 8 mg. The therapeutic response to haloperidol was similar to that seen with risperidone 16 mg. Risperidone was associated with significantly less extrapyramidal symptoms than haloperidol, as assessed by the ESRS. The effect was mirrored by the requirement for antiparkinson rescue medication. Furthermore, the overall incidence of adverse events was markedly lower with the optimum dose of risperidone than with haloperidol. CONCLUSIONS: Risperidone is at least as effective as haloperidol for the treatment of chronic schizophrenia. Moreover, risperidone is associated with an improved adverse event profile and significantly less extrapyramidal symptoms which will have beneficial implications on patient quality of life and compliance. These results are in agreement with the results from the international multicenter trial.

Use of psychotropic drugs in patients with HIV infection.

Psychotropic drugs are frequently employed to treat the wide range of neuropsychiatric syndromes that patients infected with the human immunodeficiency virus (HIV) may develop. In order to administer these agents properly, physicians should take certain factors into account: the central nervous systems of these patients are often impaired, the patients tend to suffer from medical illnesses, and they may be taking various other drugs. The possible interactions between substances taken by these patients may sometimes make it necessary to adjust the dosage of psychotropic agents administered. In addition, some of the antimicrobial, antifungal and antiviral agents used in the management of HIV infection may have adverse effects that include neuropsychiatric symptoms. The use of antipsychotic agents in these patients frequently results in the development of extrapyramidal symptoms. Tricyclic antidepressants are not well tolerated by patients with AIDS, due to the anticholinergic effects of these agents. The new antidepressants, which have fewer and milder adverse effects, are safer and have shown their efficacy in the treatment of the depressive episodes often seen in HIV-infected patients. Benzodiazepines must be prescribed with caution in patients with HIV infection and organic brain syndrome, since they can produce amnesia, confusion, lack of inhibition and paradoxical reactions. The indications for the use of psychostimulants in certain clinical situations, such as HIV-associated dementia and depression, is open to debate. Opiates are indicated in pain treatment, and in methadone maintenance programmes. Lithium and carbamazepine are advisable only in very restricted situations.

Maintenance drug therapy of panic disorder.

The efficacy of tricyclics and benzodiazepines in the short term (approximately 2-4 months) treatment of panic disorder is well demonstrated, but efficacy over the longer term is not considered established. The present study provided systematic data from a double blind comparison of maintenance therapy (up to 8 months) of panic disorder with or without agoraphobia with alprazolam, imipramine, or placebo in 181 patients who had responded to the same regimen in a randomized 8-week treatment trial. All three groups had improved during the first 2 months (active treatments more than placebo and about equal to each other), and all maintained or extended their improvement over the next 6 months without any significant change in dose. More than twice as many alprazolam and imipramine than placebo patients (15%) remained in treatment for the full 8 months and did slightly better on symptom measures than the remaining placebo patients. Both medications were well tolerated during the maintenance period. The data suggest sustained efficacy and safety of imipramine and alprazolam over an extended period. More specifically, they suggest that tolerance does not develop to the therapeutic effects of either drug.

The Hamilton scales and the Hopkins Symptom Checklist (SCL-90). A cross-national validity study in patients with panic disorders.

The HRSD, HRSA, SCL-90 scales were psychometrically investigated in a cross-national sample of patients with varieties of non-psychotic symptoms of anxiety and depression. Across the cultural backgrounds the scores obtained from the original versions of these scales are not sufficient statistics. However, latent structure analysis has identified homogeneous subscales for depression (the HRSD) and for discomfort (an SCL subscale). High concurrent validity was found between the subscales of depression, anxiety and discomfort. In international research, inhomogeneity among scale items can be confounded with group differences which are usually ascribed to drug differences.

Fluoxetine vs. clomipramine in depressed patients: a controlled multicentre trial.

A sample of 120 patients, all of whom met DSM-III criteria for major unipolar depressive disorder, were randomly allocated to two treatment groups. Sixty patients were treated with fluoxetine and 60 with clomipramine during a 6-week period. No significant difference was found in antidepressant efficacy, with improvement occurring on both drugs. Important differences were found in the side-effects profile of each group, their incidence being significantly lower and tending to disappear during the course of treatment in the group of patients treated with fluoxetine.

The Panic-Associated Symptom Scale: measuring the severity of panic disorder.

The Panic-Associated Symptom Scale (PASS) is presented as a new measurement of the severity of the core symptoms of panic disorder. This first description addresses the rationale for its design and its scoring, score distributions, test-retest reliability, correlations within the PASS and with other scales, principal component structure, and response to drug therapy. Data are presented from a large study group of patients with panic disorder (n = 1168). Problems in measuring panic disorder are discussed.

Childhood separation anxiety and panic disorder: a comparative study.

1. The relationship between childhood separation anxiety and panic disorder in adults is analyzed using data from a multicenter trial in 107 patients. 2. The patients included in this study presented anxiety disorder with or without agoraphobia, diagnosed according to DSM-III criteria. 3. The percentage of patients with antecedents of separation anxiety was 17.8% in patients without agoraphobia and 21.7% in patients with agoraphobia. These rates are significantly higher than those encountered in a group of normal controls (4%). 4. The existence of separation anxiety in childhood does not seem to significantly modify the clinical manifestations or severity of panic disorder in the adult.

Basal hypersecretion of cortisol in relation to abnormal dexamethasone suppression test response in depression.

The activity of the hypothalamus-hypophysis-adrenal axis was evaluated in a group of patients with primary affective disorder by correlation of basal cortisol hypersecretion and abnormal response to dexamethasone suppression test (DST). The increase in basal cortisol was not found to be responsible for suppression failure. Moreover, this biochemical abnormality was common in the groups of psychiatric patients studied, although the physiopathologic mechanisms involved are different. Further research is necessary to clarify the results.