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R M Post

Publications and source records attributed to R M Post.

At least 37 records · Page 2Linked to original sources
PubMed2000

Regional cerebral metabolism associated with anxiety symptoms in affective disorder patients.

BACKGROUND: We studied the relationship between regional cerebral metabolism and the severity of anxiety in mood disorder patients, controlling for depression severity. METHODS: Fifty-two medication-free patients with unipolar or bipolar illness underwent positron emission tomography with [(18)F]-fluorodeoxyglucose. Hamilton Depression Rating Scale and Spielberger Anxiety-State Scale scores were obtained for the week of the scan. Analyses were performed on globally normalized images and were corrected for multiple comparisons. RESULTS: After covarying for depression scores, age, and gender, Spielberger Anxiety-State Scale scores correlated directly with regional cerebral metabolism in the right parahippocampal and left anterior cingulate regions, and inversely with metabolism in the cerebellum, left fusiform, left superior temporal, left angular gyrus, and left insula. In contrast, covarying for anxiety scores, age, and gender, Hamilton Depression Rating Scale scores correlated directly with regional cerebral metabolism in the bilateral medial frontal, right anterior cingulate, and right dorsolateral prefrontal cortices. CONCLUSIONS: Comorbid anxiety symptoms are associated with specific cerebral metabolic correlates that partially overlap with those in the primary anxiety disorders and differ from those associated with depression severity.

Adult↗
PubMed2000

Methodological issues in developing new acute treatments for patients with bipolar illness.

One important aim of the recent reorganization of the National Institute of Mental Health (NIMH) is to streamline the development of new treatments for patients with severe mental illnesses, such as bipolar disorder. Researching new treatments for patients with bipolar disorder presents specific problems not readily addressed by traditional efficacy trial methodologies that aim to maximize internal validity. This article reexamines several assumptions that have guided the design of these efficacy trials but that also create obstacles for studies of bipolar disorder and suggests potential solutions. This article draws on literature from neurology and psychiatry and discussions at a MacArthur Foundation-sponsored Conference on Longitudinal Methodology in 1992 (David J. Kupfer, M.D., Chair), which brought together investigators to consider alternative designs for patients with severe and persistent mental illness. In addition, we benefited from discussions at two NIMH-sponsored conferences, one held in 1989 (Prien and Potter 1990) and the other in 1994 (Prien and Rush 1996), at which investigators and methodologists discussed issues surrounding the development and conduct of informative efficacy trials for patients with bipolar disorder. Based on these discussions and recent literature reviews, we 1) outline common problems in the development and evaluation of effective acute treatments for bipolar disorder and 2) suggest possible solutions to these impediments. We also discuss alternative designs by which to build a sequence of acute treatment studies from which efficacy, safety, and the comparative value of different treatments can be established.

Acute Disease↗
PubMed2000

Specific amygdaloid nuclei are involved in suppression or propagation of epileptiform activity during transition stage between oral automatisms and generalized clonic seizures.

Kindling is a model of the neural plasticity that occurs following stimulation to the brain, which can result in epileptogenesis. The amygdala (Am), one of the most sensitive structures from which to induce electrical kindling, is comprised of distinct nuclei that possess differences in threshold for seizure initiation, unique cellular and molecular morphology, and specific neuroanatomical connections within the amygdala and, to other cortical and subcortical brain structures. The aim of this study was to map the spread of epileptiform activity throughout the ipsilateral and contralateral hemispheres during the transition stage between oral automatisms and generalized clonic seizures, by measuring changes in mRNA expression for c-fos, NGFI-A, and BDNF. The stimulating electrode was implanted in either the basolateral (BL) or the lateral (CeL) or medial (CeM) subdivisions of the central nucleus of the amygdala. The rats were kindled once daily using afterdischarge-threshold electrical stimulation until the first forelimb clonic seizure was induced. They were sacrificed 30 min later, and their brains were prepared for in situ hybridization to measure mRNA expression of c-fos, NGFI-A and BDNF. The results demonstrate that: (1) the threshold to elicit an afterdischarge from the BL was lower than that of either the medial (CeM) or lateral (CeL) subdivisions of the Ce, which did not differ from each other; (2) the patterns of mRNA expression for c-fos, NGFI-A and BDNF were highly similar to each other when the stimulation site was the BL or the CeL, and included mainly limbic cortical and subcortical areas ipsilateral to the electrode; (3) c-fos was the only probe to be expressed in the contralateral hemisphere following the first motor seizure, and the pattern of its expression reflected a subset of structures recruited in the ipsilateral hemisphere including the claustrum, insular and perirhinal cortices; (4) unexpectedly, stimulation of the CeM elicited seizures and afterdischarges of shorter duration than those evoked by stimulation of the BL or CeL, and failed to increase mRNA expression for any of the probes in the hippocampus or in the contralateral hemisphere. A neuroanatomical model of Am-induced seizure propagation is proposed suggesting that the Claust-Ins-PRh play a pivotal role during the transition between oral automatisms and generalized clonic convulsions.

Amygdala↗
PubMed2000

Open-label adjunctive topiramate in the treatment of bipolar disorders.

BACKGROUND: To preliminarily explore the spectrum of effectiveness and tolerability of the new antiepileptic drug topiramate in bipolar disorder, we evaluated the response of 56 bipolar outpatients in the Stanley Foundation Bipolar Outcome Network (SFBN) who had been treated with adjunctive topiramate in an open-label, naturalistic fashion. METHODS: In this case series, response to topiramate was assessed every 2 weeks for the first 3 months according to standard ratings in the SFBN, and monthly thereafter while patients remained on topiramate. Patients' weights, body mass indices (BMIs), and side effects were also assessed. RESULTS: Of the 54 patients who completed at least 2 weeks of open-label, add-on topiramate treatment, 30 had manic, mixed, or cycling symptoms, 11 had depressed symptoms, and 13 were relatively euthymic at the time topiramate was begun. Patients who had been initially treated for manic symptoms displayed significant reductions in standard ratings scores after 4 weeks, after 10 weeks, and at the last evaluation. Those patients who were initially depressed or treated while euthymic showed no significant changes. Patients as a group displayed significant decreases in weight and BMI from topiramate initiation to week 4, to week 10, and to the last evaluation. The most common adverse side effects were neurologic and gastrointestinal. CONCLUSIONS: These preliminary open observations of adjunctive topiramate treatment suggest that it may have antimanic or anticycling effects in some patients with bipolar disorder, and may be associated with appetite suppression and weight loss that is often viewed as beneficial by the patient and clinician. Controlled studies of topiramate's acute and long-term efficacy and side effects in bipolar disorder appear warranted.

Adult↗
PubMed2000

Tolerance to the anticonvulsant effects of lamotrigine on amygdala kindled seizures: cross-tolerance to carbamazepine but not valproate or diazepam.

Using an amygdala-kindled seizure paradigm, we evaluated the acute and chronic anticonvulsant effects of lamotrigine (LTG). Lamotrigine produced dose-dependent inhibitory effects on seizure stage, afterdischarge (AD), and seizure duration. Lamotrigine (15 mg/kg) also increased the afterdischarge and seizure thresholds. Following repeated LTG administration and stimulation at 48-h intervals, tolerance developed to LTG's (15 mg/kg) anticonvulsant effects, and cross-tolerance was observed to the anticonvulsant effects of carbamazepine (CBZ, 15 mg/kg). In a separate group of kindled rats, CBZ (15 mg/kg) was repeatedly administered to induce tolerance. This led to a partial cross-tolerance to LTG, manifesting as an increased rate of tolerance development to LTG, and seizures following the first injection in some animals, which were not observed in CBZ-nontolerant controls. When these rats were made fully tolerant to LTG and then exposed to higher doses of LTG (30 and 50 mg/kg), no anticonvulsant effects were observed. In contrast, higher doses of CBZ (30 mg/kg) did restore efficacy in CBZ-tolerant animals. Cross-tolerance from LTG to valproate and diazepam was not observed, although cross-tolerance from CBZ to valproate has been reported previously. These data suggest that LTG has both shared and distinct anticonvulsant mechanisms from those of CBZ on amygdala-kindled seizures. The implications of these results for clinical therapeutics remain to be evaluated.

Amygdala↗
PubMed2000

MRI-based measurements of temporal lobe and ventricular structures in patients with bipolar I and bipolar II disorders.

OBJECTIVE: There have been relatively few quantitative MRI studies of temporal lobe structures and the lateral ventricles in bipolar patients and a lack of agreement across studies as to whether these structures differ significantly in size from control subjects. Also there have been no quantitative MRI studies of bipolar II patients. The present study measured temporal lobe and ventricular structures in both bipolar I and bipolar II patients, as well as control subjects. METHOD: Twenty-five bipolar I patients, 22 bipolar II patients and 19 control subjects underwent MRI brain scans. The 5 mm coronal slices of each subject were coded and measured by a rater who was blind with respect to subject diagnosis. Volume estimates of the temporal lobe and hippocampus were calculated for each hemisphere by measuring the area of the structure in each slice in which it appears, multiplying by 5 mm and summing. In addition to these volume estimates, the area of the lateral ventricle and the inferior horn of the lateral ventricle, the lateral ventricle to cerebrum area ratio (LV/C) and the temporal lobe to cerebrum area ratio (TL/C), were calculated for each hemisphere in one reference slice only. The area of the third ventricle was also measured. Volume estimates and area ratios were then compared among diagnostic groups. RESULTS: There were no significant differences in temporal lobe or hippocampal volume estimates, in the third ventricle and inferior horn of the lateral ventricle area measurements, and in the TL/C area ratio among diagnostic groups. The lateral ventricle area and LV/C area ratio were significantly larger in bipolar I patients than either bipolar II patients or control subjects only in the left hemisphere. Furthermore, these measures were approximately twice as large in the bipolar I patients as the other groups. CONCLUSIONS: The current study adds to a growing literature that bipolar I disorder, particularly in males, may show different neurobiological alterations compared to bipolar II patients or control subjects. The pathophysiologic implications of this accumulating evidence of increased left ventricular size in bipolar I disorder remains to be further elucidated.

Adult↗
PubMed2000

Seizure models: anticonvulsant effects of ECT and rTMS.

1. A variety of enzymes, peptides, neurotrophic factors and their receptors show complex cascades of alterations with amygdala-kindled seizure progression; some represent compensatory adaptations that could become new targets of therapeutics. 2. Non-convulsant brain stimulation with repetitive transcranial magnetic stimulation (rTMS) may be able to engage some of the neuro-adaptive effects of ECT without the necessity of inducing a seizure. 3. Data from preclinical and clinical studies raise the possibility that non-convulsant stimulation achieved by high or low frequency rTMS may be able to alter neurotransmitters, neuropeptides, and neurotrophic factors, leading to frequency- and region-dependent changes in neural excitability. 4. Individual depressed patients show differential responses to two weeks high vs. low frequency rTMS, as revealed by the inverse correlation of degree of improvement in depression achieved by these two frequencies. 5. Preliminary data from rTMS and positron emission tomography (PET) studies reveal moderately sustained differential effects of rTMS frequency on regional cerebral neural activity in depressed patients. 6. These data suggest the possibility that an individual's level of baseline rCBF or rCMRglu on PET would help predict which rTMS frequency might be the most appropriate treatment for their depression.

Amygdala↗
PubMed2000

Validation of the prospective NIMH-Life-Chart Method (NIMH-LCM-p) for longitudinal assessment of bipolar illness.

BACKGROUND: Systematic and accurate depiction of a patient's course of illness is crucial for assessing the efficacy of maintenance treatments for bipolar disorder. This need to rate the long-term prospective course of illness led to the development of the National Institute of Mental Health prospective Life Chart Methodology (NIMH-LCM-p or LCM). The NIMH-LCM-p allows for the daily assessment of mood and episode severity based on the degree of mood associated functional impairment. We have previously presented preliminary evidence of the reliability and validity of the LCM, and its utility in clinical trials. This study is a further and more extensive validation of the clinician rated NIMH-LCM-p. METHODS: Subjects included 270 bipolar patients from the five sites participating in the Stanley Foundation Bipolar Network. Daily prospective LCM ratings on the clinician form were initiated upon entry, in addition to at least monthly ratings with the Inventory of Depressive Symptomatology-clinician rated (IDS-C), the Young Mania Rating Scale (YMRS) and the Global Assessment of Functioning (GAF). We correlated appropriate measures and time domains of the LCM with the IDS-C, YMRS and GAF. RESULTS: Severity of depression on the LCM and on the IDS-C were highly correlated in 270 patients (r = -0.785, P < 0.001). Similarly, a strong correlation was found between LCM mania and the YMRS (r = 0.656, P < 0.001) and between the LCM average severity of illness and the GAF (r = -0.732, P < 0.001). CONCLUSIONS: These data further demonstrate the validity and potential utility of the NIMH-LCM-p for the detailed daily longitudinal assessment of manic and depressive severity and course, and response to treatment.

Adult↗
PubMed2000

Emerging trends in the treatment of rapid cycling bipolar disorder: a selected review.

Recent evidence suggests that lithium therapy (even as supplemented by antidepressants and neuroleptics) is inadequate for the majority of patients with bipolar illness, and particularly those with rapid cycling. Valproate and carbamazepine have emerged as adjuncts and alternatives, but they, too, often require additional approaches with lithium, thyroid hormones, and other putative mood stabilizers, including nimodipine (and related dihydropyridine calcium channel blockers), lamotrigine, gabapentin, topiramate, and the atypical neuroleptics. Evaluating how these agents and the unimodal antidepressants are optimally applied and sequenced in the treatment of bipolar illness with its multiple subtypes, patterns and comorbidities will require much future investigation and the development of new methodological clinical trial approaches.

Algorithms↗
PubMed2000

A placebo-controlled study of lamotrigine and gabapentin monotherapy in refractory mood disorders.

There is a pressing need for additional treatment options for refractory mood disorders. This controlled comparative study evaluated the efficacy of lamotrigine (LTG) and gabapentin (GBP) monotherapy versus placebo (PLC). Thirty-one patients with refractory bipolar and unipolar mood disorders participated in a double-blind, randomized, crossover series of three 6-week monotherapy evaluations including LTG, GBP, and PLC. There was a standardized blinded titration to assess clinical efficacy or to determine the maximum tolerated daily dose (LTG 500 mg or GBP 4,800 mg). The primary outcome measure was the Clinical Global Impressions Scale (CGI) for Bipolar Illness as supplemented by other standard rating instruments. The mean doses at week 6 were 274 +/- 128 mg for LTG and 3,987 +/- 856 mg for GBP. Response rates (CGI ratings of much or very much improved) were the following: LTG, 52% (16/31); GBP, 26% (8/31); and PLC, 23% (7/31) (Cochran's Q = 6.952, df = 2, N = 31, p = 0.031). Post hoc Q differences (df = 1, N = 31) were the following: LTG versus GBP (Qdiff = 5.33, p = 0.011); LTG versus PLC (Qdiff = 4.76, p = 0.022); and GBP versus PLC (Qdiff = 0.08, p = 0.70). With respect to anticonvulsant dose and gender, there was no difference between the responders and the nonresponders. The agents were generally well tolerated. This controlled investigation preliminarily suggests the efficacy of LTG in treatment-refractory affectively ill patients. Further definition of responsive subtypes and the role of these medications in the treatment of mood disorders requires additional study.

Acetates↗
PubMed2000

Lamotrigine treatment during amygdala-kindled seizure development fails to inhibit seizures and diminishes subsequent anticonvulsant efficacy.

PURPOSE: Lamotrigine (LTG) is an anticonvulsant that is currently in use for the treatment of various seizure disorders and that shows promise in the treatment of affective illness. LTG is also effective in the suppression of amygdala-kindled seizures. Because many drugs show a differential efficacy profile as a function of the phase of kindling evolution, we evaluated LTG for its potential antiepileptogenic effects on the development of amygdala-kindled seizures. METHODS: In two separate studies, LTG (5 or 15 mg/kg versus vehicle) was administered before each daily amygdala stimulation (biphasic square wave pulses, 100 pulse pairs per second for a total of 0.5 second, 1-millisecond pulse width) at an intensity of 50 microA over the AD threshold. Seizure development was assessed, as well as the effect of this pretreatment on subsequent efficacy of LTG on completed kindled seizures. RESULTS: LTG at 5 mg/kg failed to block seizure development. At 15 mg/kg, LTG paradoxically enhanced seizure development and produced running fits in four of the nine animals tested. Animals previously treated with either dose of LTG during kindling development showed a diminished response to the anticonvulsant effects of LTG on fully kindled seizures compared with the vehicle-treated controls. CONCLUSIONS: Although LTG possesses potent anticonvulsant effects on completed amygdala-kindled seizures, it is either without effect (5 mg/kg) or facilitates (15 mg/kg) the initial phase of kindling development. In addition, exposure to LTG during kindled seizure development leads to a reduced subsequent response to the drug in fully kindled animals. These observations parallel those with carbamazepine and suggest that different stages of kindling (epileptogenesis versus fully manifest seizures) may have different underlying neural mechanisms that require distinct pharmacotherapies.

Amygdala↗
PubMed2000

Development and validation of a screening instrument for bipolar spectrum disorder: the Mood Disorder Questionnaire.

OBJECTIVE: Bipolar spectrum disorders, which include bipolar I, bipolar II, and bipolar disorder not otherwise specified, frequently go unrecognized, undiagnosed, and untreated. This report describes the validation of a new brief self-report screening instrument for bipolar spectrum disorders called the Mood Disorder Questionnaire. METHOD: A total of 198 patients attending five outpatient clinics that primarily treat patients with mood disorders completed the Mood Disorder Questionnaire. A research professional, blind to the Mood Disorder Questionnaire results, conducted a telephone research diagnostic interview by means of the bipolar module of the Structured Clinical Interview for DSM-IV. RESULTS: A Mood Disorder Questionnaire screening score of 7 or more items yielded good sensitivity (0.73) and very good specificity (0.90). CONCLUSIONS: The Mood Disorder Questionnaire is a useful screening instrument for bipolar spectrum disorder in a psychiatric outpatient population.

Adolescent↗
PubMed2000

The increasing use of polypharmacotherapy for refractory mood disorders: 22 years of study.

BACKGROUND: Few studies have approached the subject of polypharmacotherapy systematically. This retrospective review of 178 patients with refractory bipolar disorder or unipolar depression (Research Diagnostic Criteria or DSM-III-R criteria) discharged from the National Institute of Mental Health (NIMH) Biological Psychiatry Branch between 1974 and 1996 was conducted to assess the degree and efficacy of "add-on" pharmacotherapy. METHOD: Following completion of formal structured blinded research protocols, patients entered a treatment phase (often again on a blind basis) in which all agents available in the community could be utilized. Each patient's retrospective life chart and all prospective double-blind nurse- and self-rated NIMH data were reviewed. The overall degree of improvement at discharge was assessed by rating on the Clinical Global Impressions scale (CGI) as modified for bipolar illness (CGI-BP). RESULTS: A 78% improvement rate (moderate or marked on the CGI) was achieved at the time of discharge. There was a significant relationship between number of medications utilized at discharge as a function of discharge date (r = 0.45, p < .0001). The percentages of patients discharged on treatment with 3 or more medications were 3.3% (1974-1979), 9.3% (1980-1984), 34.9% (1985-1989), and 43.8% (1990-1995). No correlation was found between polypharmacy and age (r = -0.03, p = .66). Patients more recently discharged from the NIMH had an earlier age at illness onset, more lifetime weeks depressed, and a higher rate of rapid cycling than patients in the earlier cohorts. CONCLUSION: Increasing numbers of medications in more recent NIMH cohorts were required to achieve the same degree of improvement at hospital discharge. More systematic approaches to the complex regimens required for treatment of patients with refractory mood disorder are clearly needed.

Adult↗
PubMed2000

High exposure to neuroleptics in bipolar patients: a retrospective review.

BACKGROUND: Acute and long-term use of neuroleptics to treat bipolar disorder remains prevalent despite safety concerns. Neuroleptic-treated patients with bipolar disorder have been reported to have rates of tardive dyskinesia, akathisia, and acute dystonia as high as or higher than patients with schizophrenia. Moreover, the pattern of repeated, intermittent use of neuroleptics in bipolar disorder may increase rather than decrease the risk of tardive dyskinesia. METHOD: Retrospective life charts of 133 treatment-refractory patients with bipolar disorder (diagnosed according to Research Diagnostic Criteria or a clinical interview with the Schedule for Affective Disorders and Schizophrenia-Lifetime Version or the Structured Clinical Interview for DSM-IV Axis I Disorders) admitted to the National Institute of Mental Health (NIMH) were reviewed for prior neuroleptic use, medication exposure, and course of illness variables. Patients' medication response and degree of improvement while at NIMH were also assessed. RESULTS: A total of 72.2% (N = 96) of the bipolar patients examined had exposure to neuroleptics prior to referral to NIMH. Neuroleptic-treated patients had a mean of 5.6 neuroleptic trials with a mean duration of 166.4 days for each trial and a dose range of 25 to 960 mg in chlorpromazine equivalents. Life chart data showed that the neuroleptic-exposed and nonexposed bipolar patients were distinguished by 1 course-of-illness variable: increased suicidality in the neuroleptic-treated group. Patients with and without prior neuroleptic exposure experienced the same high degree of improvement at discharge from NIMH. Only 12.5% (N = 12) of the group previously treated with typical neuroleptics (N = 96) required neuroleptics at discharge. CONCLUSION: Our data suggest that the majority of even treatment-refractory bipolar patients can be stabilized without neuroleptics. Given the high risk of tardive dyskinesia and the availability of other novel agents, the routine intermittent use of typical neuroleptics to treat patients with bipolar disorder should be minimized.

Adult↗
PubMed2000

A preliminary study of the relation of neuropsychological performance to neuroanatomic structures in bipolar disorder.

OBJECTIVE: To investigate the relation between neuropsychological dysfunction and volumetric measures of neuroanatomic structures in patients with bipolar disorder. BACKGROUND: Previous research suggests that neuropsychological deficits are associated with neuroanatomic changes in patients with bipolar disorder. METHOD: Twenty-six outpatients who met Diagnostic and Statistical Manual, Third Edition-Revised criteria for bipolar disorder were administered a battery of neuropsychological tests that assessed memory, abstracting ability, psychomotor performance, sustained attention, and intelligence. Patients also received a magnetic resonance imaging scan, from which volumes of the temporal lobes, hippocampus, third ventricle, and areas of the lateral ventricles were calculated. Using multiple regression analyses, neuroanatomic structures were compared with neuropsychological test variables. RESULTS: Data suggest that a larger right hippocampal volume is associated with poorer neuropsychological functioning. CONCLUSIONS: Further studies are needed to both replicate and examine the relation between potential mechanisms of neuroanatomic alterations and neuropsychological dysfunction in patients with bipolar disorder.

Adult↗
PubMed2000

Cognitive effects of 1- and 20-hertz repetitive transcranial magnetic stimulation in depression: preliminary report.

OBJECTIVE: To determine the cognitive effects of daily repetitive transcranial magnetic stimulation (rTMS) administered under the conditions of a treatment trial for major depression. BACKGROUND: Although daily left dorsal prefrontal rTMS has improved mood in some patients with treatment-refractory depression, potential cognitive side effects of extended daily treatment have not been systematically studied. METHOD: In a randomized double-blind treatment study, 10 subjects (mean age, 42 +/- 15 years) with an episode of major depression received either 2 weeks of low-frequency (1 Hz) or high-frequency (20 Hz) rTMS (800 pulses, 20 trains over 20 minutes, 80% of motor threshold, 5 days per week) to the left dorsolateral prefrontal cortex and then were crossed over to the other treatment condition. Patients received cognitive testing at baseline and after the first and second weeks of low- or high-frequency rTMS, which was examined by repeated-measures ANOVA. RESULTS: Of 16 cognitive measures tested after 1 or 2 weeks of rTMS compared with baseline status, none showed deterioration, and the only significant main treatment effect indicated improvement on a list-recall test from pre- to post-rTMS after 1 week (p <0.05). CONCLUSIONS: These preliminary data suggest no gross deleterious cognitive effects of 2 weeks of 1- or 20-Hz rTMS at 80% of motor threshold over the left prefrontal cortex. Further cognitive studies of the effects of rTMS at other parameters used in clinical trials for mood disorders remain to be undertaken.

Adult↗