Will a second prophylactic treatment with a higher dosage of the same antidepressant either prevent or delay new depressive episodes?

Selective Serotonin Reuptake Inhibitors: How Long Is Long Enough?

Selective serotonin reuptake inhibitors (SSRIs) are among the most commonly prescribed medications. They are among the first-line medications for several chronic or relapsing-remitting psychiatric conditions, including major depressive disorder and anxiety disorders. The advantages of SSRI use include ease of titration and their tolerability and safety profile. Guidelines for the short-term use of SSRIs are widely available, but there is no well-organized guidance on how and whether to maintain a patient on SSRIs for the long-term. In this article, we discuss the benefits and possible adverse consequences of long-term SSRI use, as well as clinical practice considerations when using SSRIs chronically. The major benefit of long-term SSRI use is relapse prevention. The current literature suggests that the general health risks of long-term SSRI use are low; however, further research, particularly in special populations including youth and the elderly, is needed. Long-term SSRI use increases the risk of tachyphylaxis and discontinuation syndrome. Recognizing that many patients may remain on SSRIs for many years, there are several factors that prescribers should consider if they choose to use an SSRI when initiating treatment and during long-term monitoring. The decision to continue or to discontinue an SSRI should be an active one, involving both the patient and prescriber, and should be revisited periodically. Patients who remain on SSRIs for the long-term should also have periodic monitoring to reassess the risk-benefit ratio of remaining on the SSRI, as well as to assess the safety, tolerability, and efficacy of the medication.

May antidepressant drugs worsen the conditions they are supposed to treat? The clinical foundations of the oppositional model of tolerance

In recent years there has been a considerable debate on antidepressant drugs. Continued drug treatment with antidepressant medications may stimulate processes that run counter to the initial acute effects of a drug. The oppositional model of tolerance may explain loss of treatment efficacy during maintenance treatment and the fact that some side effects tend to occur only after a certain time. These processes may also direct the illness into a treatment-unresponsive course, including manifestations of bipolar disorder or paradoxical reactions. When drug treatment ends, oppositional processes no longer encounter resistance, resulting in potential onset of new withdrawal symptoms, persistent post-withdrawal disorders, hypomania, and resistance to treatment if it is reinstituted. In all these cases, antidepressant medications may constitute a form of iatrogenic comorbidity, which increases chronicity and vulnerability to depressive episodes. Antidepressant medications are essential drugs for the treatment of major depressive episodes. They are less likely, however, to provide protection for relapse prevention. Current prescription practices need to be reformulated in light of consideration of vulnerabilities and adverse effects of treatment. The oppositional model of tolerance provides a conceptual framework for weighing all these elements in the individual case. The model does not appear to apply to all patients who undergo treatment with AD, but only to a part of them. Studying the variables that are associated with such occurrence in certain patients and not in others would be one of the most important tasks of current therapeutic research. Current diagnostic systems in psychiatry do not consider the iatrogenic components of psychopathology, and can be applied to only patients who are drug free. They are suited for a patient who no longer exists: most of the cases that are seen in psychiatric clinical practice receive psychotropic drugs and such treatment is likely to affect prognosis and treatment choices.

Evidence-based guidelines for treating depressive disorders with antidepressants: A revision of the 2008 British Association for Psychopharmacology guidelines

A revision of the 2008 British Association for Psychopharmacology evidence-based guidelines for treating depressive disorders with antidepressants was undertaken in order to incorporate new evidence and to update the recommendations where appropriate. A consensus meeting involving experts in depressive disorders and their management was held in September 2012. Key areas in treating depression were reviewed and the strength of evidence and clinical implications were considered. The guidelines were then revised after extensive feedback from participants and interested parties. A literature review is provided which identifies the quality of evidence upon which the recommendations are made. These guidelines cover the nature and detection of depressive disorders, acute treatment with antidepressant drugs, choice of drug versus alternative treatment, practical issues in prescribing and management, next-step treatment, relapse prevention, treatment of relapse and stopping treatment. Significant changes since the last guidelines were published in 2008 include the availability of new antidepressant treatment options, improved evidence supporting certain augmentation strategies (drug and non-drug), management of potential long-term side effects, updated guidance for prescribing in elderly and adolescent populations and updated guidance for optimal prescribing. Suggestions for future research priorities are also made.

The mechanisms of tolerance in antidepressant action

There is increasing awareness that, in some cases, long-term use of antidepressant drugs (AD) may enhance the biochemical vulnerability to depression and worsen its long-term outcome and symptomatic expression, decreasing both the likelihood of subsequent response to pharmacological treatment and the duration of symptom-free periods. A review of literature suggesting potential side effects during long treatment with antidepressant drugs was performed. Studies were identified electronically using the following databases: Medline, Cinahl, PsychInfo, Web of Science and the Cochrane Library. Each database was searched from its inception date to April 2010 using "tolerance", "withdrawal", "sensitization", "antidepressants" and "switching" as key words. Further, a manual search of the psychiatric literature has been performed looking for articles pointing to paradoxical effects of antidepressant medications. Clinical evidence has been found indicating that even though antidepressant drugs are effective in treating depressive episodes, they are less efficacious in recurrent depression and in preventing relapse. In some cases, antidepressants have been described inducing adverse events such as withdrawal symptoms at discontinuation, onset of tolerance and resistance phenomena and switch and cycle acceleration in bipolar patients. Unfavorable long-term outcomes and paradoxical effects (depression inducing and symptomatic worsening) have also been reported. All these phenomena may be explained on the basis of the oppositional model of tolerance. Continued drug treatment may recruit processes that oppose the initial acute effect of a drug. When drug treatment ends, these processes may operate unopposed, at least for some time and increase vulnerability to relapse. Antidepressant drugs are crucial in the treatment of major depressive episodes. However, appraisal and testing of the oppositional model of tolerance may yield important insights as to long-term treatment and achievement of enduring effects.

Evidence-based guidelines for treating depressive disorders with antidepressants: a revision of the 2000 British Association for Psychopharmacology guidelines

A revision of the 2000 British Association for Psychopharmacology evidence-based guidelines for treating depressive disorders with antidepressants was undertaken to incorporate new evidence and to update the recommendations where appropriate. A consensus meeting involving experts in depressive disorders and their management was held in May 2006. Key areas in treating depression were reviewed, and the strength of evidence and clinical implications were considered. The guidelines were drawn up after extensive feedback from participants and interested parties. A literature review is provided, which identifies the quality of evidence to inform the recommendations, the strength of which are based on the level of evidence. These guidelines cover the nature and detection of depressive disorders, acute treatment with antidepressant drugs, choice of drug versus alternative treatment, practical issues in prescribing and management, next-step treatment, relapse prevention, treatment of relapse, and stopping treatment.

Effects of the South American psychoactive beverage ayahuasca on regional brain electrical activity in humans: a functional neuroimaging study using low-resolution electromagnetic tomography

Ayahuasca, a South American psychotropic plant tea obtained from Banisteriopsis caapi and Psychotria viridis, combines monoamine oxidase-inhibiting beta-carboline alkaloids with N,N-dimethyltryptamine (DMT), a psychedelic agent showing 5-HT(2A) agonist activity. In a clinical research setting, ayahuasca has demonstrated a combined stimulatory and psychedelic effect profile, as measured by subjective effect self-assessment instruments and dose-dependent changes in spontaneous brain electrical activity, which parallel the time course of subjective effects. In the present study, the spatial distribution of ayahuasca-induced changes in brain electrical activity was investigated by means of low-resolution electromagnetic tomography (LORETA). Electroencephalography recordings were obtained from 18 volunteers after the administration of a dose of encapsulated freeze-dried ayahuasca containing 0.85 mg DMT/kg body weight and placebo. The intracerebral power density distribution was computed with LORETA from spectrally analyzed data, and subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Statistically significant differences compared to placebo were observed for LORETA power 60 and 90 min after dosing, together with increases in all six scales of the HRS. Ayahuasca decreased power density in the alpha-2, delta, theta and beta-1 frequency bands. Power decreases in the delta, alpha-2 and beta-1 bands were found predominantly over the temporo-parieto-occipital junction, whereas theta power was reduced in the temporomedial cortex and in frontomedial regions. The present results suggest the involvement of unimodal and heteromodal association cortex and limbic structures in the psychological effects elicited by ayahuasca.

Brain regions activated during an auditory discrimination task in insomniac postmenopausal patients before and after hormone replacement therapy: low-resolution brain electromagnetic tomography applied to event-related potentials

Electrical sources of auditory event-related potentials (ERPs) determined by means of low-resolution brain electromagnetic tomography (LORETA) in 48 unmedicated insomniac postmenopausal patients aged between 46 and 67 years were compared with those obtained in 48 age-matched normal female controls. Subsequently, the patients were included in a double-blind, placebo-controlled, comparative, randomized 3-arm trial phase - Climodien 2/3 [estradiol valerate (EV) 2 mg + the progestin dienogest 3 mg] was compared with EV 2 mg and placebo - followed by an open-label phase in which all of them received Climodien 2/2 (EV 2 mg + dienogest 2 mg). The double-blind and the open-label phase lasted 2 months. ERPs were recorded from 19 EEG leads in a two-tone oddball paradigm and electrical sources of standard N1 and P2 as well as target N2 and P300 components were estimated. In both patients and controls, LORETA revealed an activation of the superior temporal gyrus [auditory cortex, Brodmann areas (BA) 41, 42, 22] for all four components. For standard P2, an additional activation was observed medially parietally in the precuneus (BA 7, 5). For target N2, also a medial frontal source (BA 9, 10, 32) was identified. Finally, for the target P300 component - in addition to the aforementioned sources - activations in the prefrontal cortex (BA 9, 10, 46, 47), the inferior parietal cortex (supramarginal gyrus, BA 40, 39) and the posterior cingulum (BA 31) were found. Thus, patients and controls did not differ in the structural processes engaged in these fundamental aspects of information processing. However, patients demonstrated significantly reduced source strength - for standard ERP components predominantly in the temporal lobe and for target components predominantly in the frontal lobe, indicating reduced energetic resources available for perceptual and cognitive demands of the discrimination task. While, as compared with placebo, estrogen alone had only minor effects on ERP source strength, Climodien generally increased the impressed current density at the ERP peak latencies, predominantly in the temporal lobe, indicating an increased stimulus-induced cortical arousal in the primary and higher-order auditory cortex. Specifically, Climodien enhanced P300 source strength in the left middle temporal gyrus and in the left superior frontal gyrus, brain regions that on the one hand have been shown to be affected by hormone therapy in positron emission tomography and functional magnetic resonance neuroimaging studies and that on the other hand are among those critical for encoding and memory processes.

Older community residents with depression: long-term treatment with sertraline. Randomised, double-blind, placebo-controlled study

BACKGROUND

Despite a growing use of selective serotonin reuptake inhibitors in older people, only one trial has examined their prophylactic efficacy in people aged 65 years and over.

AIMS

To examine the efficacy of sertraline in preventing the recurrence of depression in older people living in the community.

METHOD

Participants were openly treated with sertraline and then randomised into a double-blind, placebo-controlled continuation/maintenance study of about 2 years duration. Drug dosage was maintained at levels that achieved remission.

RESULTS

No significant difference between the sertraline and placebo groups was found in the proportion of recurrences (-7.9%; 95% CI -28.06 to 12.23). Increased age and minor residual symptoms during the continuation phase were associated with recurrence.

CONCLUSIONS

Sertraline at therapeutic dosage does not provide significant protection against recurrence.

Clonazepam in the long-term treatment of patients with unipolar depression, bipolar and schizoaffective disorder

The value of a long-term treatment with clonazepam in the prophylaxis of affective disorder is discussed controversially in the scientific literature. Altogether there are only a few reports on the use of this compound as a mood stabilizer, most of them describing patients suffering from bipolar affective disorder. The aim of this investigation was to evaluate clonazepam as a phase prophylactic medication in affective disorder. We conducted a retrospective chart review in 34 out-patients of our lithium clinic (15 suffering from unipolar depression, 15 from bipolar disorder, four from schizoaffective disorder), who had been treated with clonazepam as a long-term medication. Clonazepam was either given as monotherapy, or as in the case of lithium non-responders, as adjunctive therapy. Patients with unipolar depression had significantly (P=0.026) less depressive episodes after initiation of treatment with clonazepam. Patients with bipolar disorder did not benefit from this therapy. Neither manic/hypomanic phases nor depressive episodes were reduced in this group of patients. Interestingly, clonazepam also reduced affective phases in our four schizoaffective patients on a trend level. Our results indicate that patients with unipolar depression may benefit from a maintenance treatment with clonazepam. Due to methodological limitations our results need to be replicated in controlled double-blind randomized clinical trials.

Long-term treatment with citalopram in patients with highly recurrent forms of unipolar depression

The authors evaluated the efficacy and safety of citalopram in a 28-month study in 48 inpatients with highly recurrent forms of unipolar depression. The patients, who each had at least one depressive episode during the 18 months preceding the index episode, were openly treated with citalopram, 40 mg/day. Thirty-six of the patients had a stable response to citalopram and continued treatment as outpatients for 4 months. No relapses were observed. At the time of recovery, 32/36 subjects received maintenance treatment with citalopram (40 mg) for an additional 24 months. At the end of the study, 11/32 patients experienced a single new recurrence.