Proposals for the mechanism of action of convulsive therapy: a synthesis

Non-invasive brain stimulation for fibromyalgia: current trends and future perspectives

Fibromyalgia, a common and enduring pain disorder, ranks as the second most prevalent rheumatic disease after osteoarthritis. Recent years have witnessed successful treatment using non-invasive brain stimulation. Transcranial magnetic stimulation, transcranial direct current stimulation, and electroconvulsion therapy have shown promise in treating chronic pain. This article reviews the literature concerning non-invasive stimulation for fibromyalgia treatment, its mechanisms, and establishes a scientific basis for rehabilitation, and discusses the future directions for research and development prospects of these techniques are discussed.

Is successful electroconvulsive therapy related to stimulation of the vagal system?

BACKGROUND

Electroconvulsive therapy (ECT) has been shown to exhibit strong beneficial effects in the treatment of major depressive disorder (MDD). While the exact underlying mechanisms are under debate, a role for the sympathetic response upon ECT has been suggested. When assessing patients with MDD for autonomic function, however, a loss of vagal function is prominent.

OBJECTIVE

Here, we aimed to assess the immediate effects of ECT on vagal activity and to test the hypothesis that surrogates of the latter correlate with therapeutic outcome.

METHODS

Twenty patients with MDD who underwent ECT treatment were assessed regarding their vagal function using electrophysiological measures and determination of pancreatic polypeptide (PP), which is known to be released upon vagal stimulation. Parameters were correlated to the improvement of disease severity upon ECT treatment.

RESULTS

Patients showed a significant increase of PP shortly after ECT which correlated with clinical improvement. Furthermore, the described association with the sympathetic phase after ECT could be verified.

CONCLUSION

ECT increases vagal activity which might be associated with the beneficial effect seen following this treatment. PP elevation after administration of ECT might be a useful parameter to estimate the degree of such vagal stimulation after treatment.

Dinâmica não-linear e psiquiatria: a natureza dinâmica das doenças mentais

A psiquiatria moderna adotou a postura reducionista de associar psicopatologia à fisiologia sináptica. Isto produziu avanços importantes na farmacoterapia dos transtornos mentais. Entretanto, a introdução de princípios da dinâmica não-linear promoveu uma mudança do enfoque sináptico para o enfoque das vias específicas patologicamente autônomas envolvidas nos fenômenos psicopatológicos. Esta tendência teve início nos anos 1990 e trouxe um conceito mais sistêmico de fisiopatologia e tratamento em psiquiatria.

Sudden amnesia resulting in pain relief: the relationship between memory and pain

Nociceptive pain and its emotional component can result in the development of a "chronic pain memory". This report describes two patients who had long histories of chronic pain and opioid dependence. Both patients experienced sudden memory loss that was followed by significant pain reduction and an eradication of their need for opioid management. Neural centers involved in sensory pain, its affective component, opioid dependence, and memory overlap in the brain and share common pathways. The anterior cingulate cortex, the insular cortex, and the amygdala are examples of regions implicated in both pain and memory. One of the patients in the report experienced multiple seizure episodes, which may have contributed to memory loss and pain relief. The role of electroconvulsive therapy as it relates to amnesia and pain is reviewed. Questions are raised regarding whether therapies that address the memory component of pain may have a role in the treatment of long-term chronic pain patients.

A case-matching study of the analgesic properties of electroconvulsive therapy

OBJECTIVE

Chronic pain improves with electroconvulsive therapy (ECT), yet few case reports account for treatment of comorbid major depression, a significant confounder of the analgesia of ECT. This study reports on the analgesia of ECT, controlling for treatment of depression.

METHODS

This is a case-matching study comparing outcomes of inpatients with chronic pain and major depression in a multidisciplinary pain treatment unit treated with ECT and medications (cases) with those of inpatients treated with medications only (controls). Both groups received the same behavioral and pharmacological treatments for depression and chronic pain. Outcome measures included 0-10 pain rating scales and the Montgomery-Asberg Depression Inventory. Patients were matched on sex, age within 5 years, admission date within 6 months, psychiatric diagnoses, and, as much as possible, on race and pain syndrome diagnosis. Percentage changes in depression scores and pain scores were calculated from the beginning to the end of admission.

RESULTS

There were nonsignificant differences in demographics, except in the proportion married. Twenty-five of 28 ECT patients were matched. Depression improvements were similar between cases and controls (55.9% vs 40.5%). Despite higher initial pain (8.1 vs 6.9 on a 10-point scale), the ECT group had less final pain (3.4 vs 5.5). The ECT group had a 59.8% drop in pain versus a 15.8% drop in the control group, P > 0.01.

CONCLUSIONS

ECT has analgesic properties independent of its improvement of depression in patients with chronic pain and major depression. Improvements in depression were similar, while there was a significantly greater improvement in pain with ECT. The lower post-ECT treatment pain scores suggest a specific analgesic effect of ECT.

Manic patients receiving ECT in a Brazilian sample

BACKGROUND

Characterization of manic inpatients receiving electroconvulsive therapy (ECT) has not been done.

METHODS

The charts of 425 consecutive admissions of 269 inpatients treated for manic or mixed episodes, between 1996 and 2000, in a Brazilian private psychiatric hospital were reviewed. A logistic model was built to determine the predictors of use of ECT for mania. Median total length of stay (LOS) and LOS deducted from the delay until ECT was started were compared between ECT and non-ECT admissions. The risk of readmission was estimated using Cox's regression.

RESULTS

Significant predictors of ECT prescription were: history of previous admission (OR=4.09), psychotic features (OR=1.60), female gender (OR=2.04), married (OR=1.79), and treatment by a psychiatrist who assisted more than 20 manic inpatients in the index period (OR=1.97). Co-morbidity with cardiovascular disease was negatively associated with ECT use (OR=0.49). Median LOS after starting ECT was similar to that of non-ECT admissions (12 vs. 13 days). ECT reduced (HR=0.678) and previous psychiatric admissions increased (HR=2.320) the risk of readmission after a manic episode.

LIMITATIONS

Only one hospital was included in this study.

CONCLUSIONS

The presence of psychotic features and violent behavior during manic episodes and indicators of chronicity of bipolar illness (history of previous admissions, duration of disease) were predictors of ECT use for the treatment of mania. Suicidality was not associated with the use of ECT for mania. LOS after ECT was started was similar to LOS of non-ECT admissions. The use of ECT for mania reduced the risk of readmission.

No early effects of electroconvulsive therapy on tryptophan metabolism and disposition in endogenous depression

The possibility that a single electroconvulsive therapy (ECT) could increase tryptophan (Trp) availability to the brain for 5-hydroxytryptamine (5-HT, serotonin) synthesis was examined in 10 depressed patients before and during the 1st hour following an ECT and in 4 control (minor ear, nose, and throat surgical) subjects receiving similar premedication. Trp availability to the brain, expressed as the serum Trp: competing amino acid ratio, and related aspects of Trp disposition were not significantly altered by ECT any differently than from preoperative stress and premedication. We suggest that Trp availability to the brain and, hence, cerebral 5-HT synthesis are not altered in depressed patients early after a single ECT.

Depressive illness and the possibilities of somatic antidepressant treatment

Depression constitutes a considerable mental health problem. Depression is too often unrecognized or unproperly treated, which causes distress, social impairment, and increased risk of mortality for the individual, and large costs for society. However, several efficient treatment modalities and strategies exist. Different somatic antidepressant treatments for short- and long-term therapy and their respective quality-of-life and economic aspects will be presented and discussed.

Repeated electroconvulsive stimuli: changes in neuropeptide Y, neurotensin and tachykinin concentrations in time

1. The effects of repeated electroconvulsive stimuli (ECS) on neuropeptide Y (NPY)-, neurokinin A (NKA)-, substance P (SP)- and neurotensin (NT)- like immunoreactivity (-LI) levels in specific rat brain regions were studied in order to establish changes in peptide tissue concentrations in time after the last ECS. 2. The rats were sacrificed 15 minutes, 60 minutes, 1 day, 7 days or 15 days after the sixth sham ECS or ECS, using focused microwave irradiation. 3. Following dissection of the brains, peptides were extracted and measured in extract aliquots by radioimmunoassays. 4. ECS increased NPY-LI in both right and left hippocampus, frontal cortex and occipital cortex at 15 min, 60 min and 1 day after the treatments. Seven days following the last treatment, NPY-LI concentrations were elevated in the left hippocampus and occipital cortex but not in the corresponding right structures. Fifteen days following the last ECS treatment no changes in NPY concentrations were seen. 5. Also NKA-LI was increased in both the right and left hippocampus; the duration of changes was identical to those of NPY-LI. 6. No effects on SP- or NT-LI were found. 7. These results are in line with our hypothesis that one of the ECT's mechanisms of action might involve its effects on NPY and NKA.

Prolactin response to electroconvulsive shock in anesthetized rats

Serum prolactin level (SPL) of anesthetized rats was measured in response to electroconvulsive shock (ECS). This measurement served as an indicator of dopaminergic and serotonergic activity. Such neurotransmitter activity was modulated by pretreatment with cyproheptadine, parachlorophenylalanine (PCPA), pimozide, bromocriptine or L-dopa. A statistically significant lowered SPL was found in rats given ECS plus antiserotonergic agents, in comparison with animals receiving antiserotonergic agent or ECS alone. When ECS was administered to rats pretreated with the dopaminergic blocker, pimozide, there was a significant decrease in SPL, compared with animals receiving pimozide alone. When the dopaminergic system was stimulated by dopamine agonists, there was no elevation of SPL in response to ECS. Thus, there may be a balance between serotonergic and dopaminergic systems. The agents used in the experiment may upset this balance and produce a change in prolactin response to a given ECT stimulus.

Electroconvulsive stimuli and brain peptides: effect of modification of seizure duration on neuropeptide Y, neurokinin A, substance P and neurotensin

We studied the effects of modification of duration of seizures induced by electroconvulsive stimuli (ECS) on the changes in concentration of neuropeptide Y (NPY), neurokinin A (NKA), substance P (SP) and neurotensin (NT)-like immunoreactivity (-LI) in specific rat brain regions. Rats were divided into groups pretreated with saline, indomethacin, flurbiprofen or diazepam prior to either six sham ECSs or six ECSs. After sacrifice by focused microwave irradiation, brains were dissected into frontal cortex, occipital cortex, striatum, hippocampus, pituitary and hypothalamic sections. Peptides were extracted and measured in extract aliquots by specific radioimmunoassays. Repeated ECS increased NPY-LI and NKA-LI in the hippocampus and the occipital cortex. No effect on SP-LI or NT-LI was found. Indomethacin and flurbiprofen had no effect on the tonic seizure time following ECS, and they did not affect the ECS-induced alterations of the brain peptides. Diazepam pretreatment decreased the tonic seizure time following ECS in a dose-dependent manner. However, diazepam did not modify the ECS-induced increase in NPY-LI and NKA-LI concentrations. The results firmly establish that ECS leads to specific peptide increases in discrete rat brain regions and raise the possibility that such changes may not entirely be a consequence of seizures per se.

Brain neuropeptides: changes by treatment with the convulsants pentylenetetrazole and bicuculline

1. The effects of chemically induced convulsions, clinically similar to those elicited by electroconvulsive treatment (ECT), on brain regional distribution of neuropeptide Y-, neurokinin A-, substance P- and neurotensin-like immunoreactivities were studied in the rat. 2. Pentylenetetrazole (PTZ) and bicuculline (BIC) were used to induce grand mal seizures. Rats were divided into three groups receiving one of the following treatments: Saline, PTZ (45 mg/kg) or BIC (1.5 mg/kg). 3. After sacrifice by focused microwave irradiation, brains were dissected, peptides extracted and measured by specific radioimmunoassays. 4. Repeated grand mal convulsions induced by PTZ, in similarity to ECT, markedly increased NPY-LI concentrations in frontal cortex and hippocampus. In contrast to ECT, no changes in NKA- or SP-LI levels were seen. NT-LI was lowered in striatum. 5. Bicuculline effects were more circumscribed: some animals developed grand mal and died while convulsing (peptides not measured), others did not develop generalized seizures and were sacrificed after the fourth treatment. 6. The results demonstrate a similar effect of PTZ and ECT on regional NPY-LI concentrations and raise the possibility that grand mal, regardless of etiology, is necessary for effects on peptides.

Electroconvulsive therapy. Current concepts

Recent developments in the practice and theory of ECT are reviewed. Indications, efficacy, and risk/benefit considerations are discussed with emphasis on the clinical utility and cost-effectiveness of increased and earlier usage of ECT in hospitalized patients. Treatment procedures are presented in some detail with listings of medical considerations, management of complications, and other applications to general hospital practice. Research on the mechanism of action, potential future developments, and some training issues are briefly discussed.