A placebo-controlled 18-month trial of lamotrigine and lithium maintenance treatment in recently depressed patients with bipolar I disorder

Safety considerations in pharmacotherapy of bipolar disorder

Bipolar disorder is a chronic, frequently relapsing illness with a prevalence of 1.2% to 3.4% in the general population. It is associated with high disability, higher comorbidity due to medical illnesses, and significant social and economical consequences for patients, their families, and society. The episodic nature of this disease warrants rational use of medications and proper monitoring for adverse events. Various drug classes, such as mood stabilizers, antipsychotics, benzodiazepines, and antidepressants, are used for the acute and maintenance treatment of bipolar disorder. Each group of drugs is associated with wide array of adverse events and drug interactions, which are the main hurdles in treatment outcome and compliance. Common side effects seen with several agents, particularly antipsychotics, are somnolence, weight gain, extrapyramidal symptoms, dyslipidemia, type-2 diabetes, and hyperprolactinemia. Major drug interactions are seen with drugs such as carbamazepine, due to hepatic enzyme induction. Adverse effects such as somnolence are tolerability concerns and can be managed easily; others, such as diabetes mellitus, are safety concerns. It is prudent to have precise knowledge of the individual drug's side-effect profile, pharmacokinetics, and pharmacodynamics, to plan a treatment regimen. More research is needed to understand potential risks of various drugs and to devise and incorporate monitoring protocols in the treatment regimen.

Anticonvulsivantes e antipsicóticos no tratamento do transtorno bipolar

O transtorno bipolar é uma condição médica complexa e até o momento não há um tratamento único comprovadamente eficaz no controle de todos aspectos da doença. Foram revisadas a literatura disponível sobre o uso de anticonvulsivantes (valproato, carbamazepina, oxcarbazepina, lamotrigina, gabapentina, topiramato, clonazepam) e antipsicóticos atípicos (clozapina, risperidona, olanzapina, quetiapina, ziprasidona e aripiprazole) no tratamento agudo e profilático do transtorno bipolar. Existe um acúmulo de evidências acerca da eficácia do lítio na profilaxia e de ser melhor no tratamento da mania aguda do que nos episódios depressivos. Outros dados indicam que a carbamazepina e o valproato são eficazes na mania aguda. A lamotrigina parece reduzir ciclagem e ser eficaz em episódios depressivos. Baseado nas informações disponíveis, as evidências apontam a olanzapina como o antipsicótico atípico mais apropriado no tratamento de pacientes bipolares em mania, embora existam estudos sugerindo a eficácia da risperidona, aripiprazol e da clozapina. Resultados preliminares avaliando a eficácia de ziprasidona e quetiapina no transtorno bipolar ainda são bastante limitadas. Não há dados consistentes apoiando o uso profilático dos novos antipsicóticos.

Quality of life in patients with bipolar I depression: data from 920 patients

OBJECTIVE

To determine the impact of acute depression on quality of life (QOL) in patients with bipolar I disorder and to compare these results with published data on QOL in patients with unipolar depression.

METHODS

Quality of life was assessed using the SF-36 in bipolar patients (n = 958) who had recently experienced an episode of acute bipolar depression and participated in a large randomized, double-blind, safety and efficacy trial. Seven studies that included SF-36 data from patients with unipolar depression were identified in the published literature and descriptive comparisons of SF-36 scores were made between the unipolar depression trials and this bipolar depression trial.

RESULTS

There were 920 patients who completed the SF-36. Mean transformed scores, which could range from 0 to 100, were very low in bipolar depressed patients for the role-physical (36.7), vitality (22.4), social functioning (29.9), role-emotion (11.4), and mental health (31.0) subscales. Mean SF-36 scores for all subscales were significantly and inversely correlated (p < 0.0001) with the HAM-D indicating that patients with milder depressive symptoms had better QOL. Further, the mean SF-36 scores for the bipolar sample were consistently lower compared with published data on QOL in unipolar depression on four of the eight subscales: general health; social functioning; role-physical, and role-emotional.

CONCLUSIONS

While both unipolar and bipolar depression have serious detrimental effects on patient QOL, our results suggest that some aspects of QOL may be worse in bipolar depression.

Placebo-controlled trial of lamotrigine added to conventional and atypical antipsychotics in schizophrenia

BACKGROUND

Lamotrigine, a novel anticonvulsant drug having modulatory effects on glutamatergic neurotransmission, improves mood and cognition parameters in bipolar disorder. Recent studies suggest that when added to clozapine, lamotrigine treatment may result in significant positive symptoms reductions in schizophrenia. Similar effects were not observed in an open trial in which lamotrigine was used as adjuvant to nonclozapine antipsychotics.

METHODS

Thirty-eight treatment-resistant schizophrenia inpatients receiving conventional and atypical antipsychotics enrolled in a 10-week, double-blind, placebo-controlled study, in which they were randomized in a 2:1 ratio to receive adjuvant treatment with lamotrigine, gradually titrated to a 400 mg/day dose, or placebo. Of these, 31 completed the trial. Measures of clinical efficacy and side effects were determined every other week. Serum levels of amino acids were assessed at the beginning and end of the study.

RESULTS

In primary last observation carried forward analysis, no statistically significant between-group differences were observed; however, the completers' analyses revealed that lamotrigine treatment resulted in significant (p < or = .05) reductions in positive and general psychopathology symptoms, as measured by the Positive and Negative Syndrome Scale. No significant differences in lamotrigine effects were noted between conventional versus atypical antipsychotics. Lamotrigine treatment was well tolerated, and glutamate serum levels remained stable throughout the study.

CONCLUSIONS

These preliminary findings 1) support the hypothesis that lamotrigine adjuvant treatment may improve positive symptoms and general psychopathology in schizophrenia, 2) suggest that beneficial effects may be achieved when lamotrigine is added to both conventional and atypical antipsychotics, and 3) warrant additional, larger scale trials.

Anticonvulsant drug or neuromodulator? The growing case for anticonvulsant uses beyond epilepsy

Epilepsy drugs were often used for other disorders before their effectiveness in epilepsy was fully appreciated, and the efficacy of newer antiepileptic drugs for conditions other than epilepsy is now being studied.

Rethinking the treatment paradigm for bipolar depression: the importance of long-term management

The need for long-term management of bipolar disorder is evident. Bipolar patients spend more time depressed than manic; however, few agents used for maintenance therapy of bipolar disorder have demonstrated good efficacy in delaying relapse into depression. This article provides a comprehensive review of open-label and randomized, controlled studies examining prophylactic efficacy in bipolar disorder, especially bipolar depression. Lithium, considered the gold standard for bipolar disorder maintenance therapy may be more effective in delaying manic relapse than in delaying depressive relapse. Evidence for the efficacy of divalproex and carbamazepine in delaying depressive relapse is yet to be fully elucidated. Lamotrigine has demonstrated efficacy in delaying time to depressive relapse. Unpublished studies show olanzapine's efficacy in preventing manic recurrence, while its efficacy in preventing depressive recurrence is yet to be proven. As patients with bipolar disorder are prone to experiencing depressive episodes, more attention needs to be focused on preventing depressive relapse. To date, three agents--lithium, lamotrigine, and olanzapine--have been shown to have prophylactic benefits in treating this highly recurrent disorder.

New medication treatment options for bipolar disorders

OBJECTIVE

To assess new treatment options for bipolar disorders.

METHOD

Controlled studies of new treatments for bipolar disorders were identified by computerized searches and reviews of scientific meeting proceedings, and were compiled by drug category.

RESULTS

Two main categories of medications, newer anticonvulsants and newer antipsychotics, are yielding emerging new treatment options for bipolar disorders. Newer anticonvulsants have diverse psychotropic profiles, and although not generally effective for acute mania, may have utility for other aspects of bipolar disorders (e.g. lamotrigine for maintenance or acute bipolar depression), or for comorbid conditions (e.g. gabapentin for anxiety or pain, topiramate for obesity, bulimia, alcohol dependence, or migraine, and zonisamide for obesity). In contrast, newer antipsychotics generally appear effective for acute mania, and some may ultimately prove effective in acute depression (e.g. olanzapine combined with fluoxetine, quetiapine) and maintenance (e.g. olanzapine).

CONCLUSION

Emerging research is yielding new treatment options for bipolar disorders and comorbid conditions.

Major advances in bipolar disorder

There have been major advances in clinical understanding and treatment of bipolar disorder over the past decade. Randomised controlled trials of pharmacological treatments and psychological interventions have shown that there are effective short-term and long-term treatments for the disorder. Despite advances in treatment, diagnosis is often delayed or mistaken, and many people who could benefit are not using the treatments available. Functional and symptomatic recovery from episodes of bipolar disorder is frequently less complete than previously considered, and disability is often profound. Although manic episodes are the distinguishing feature of bipolar disorder, it appears that depression is the predominant mood disturbance and that much of the functional impairment associated with bipolar disorder results from this. Comorbidity with anxiety disorders or substance misuse is common. Advances in genetics, brain imaging and basic pharmacology are starting to provide understanding of the complex causative processes.

Australian and New Zealand clinical practice guidelines for the treatment of bipolar disorder

BACKGROUND

The Royal Australian and New Zealand College of Psychiatrists is co-ordinating the development of clinical practice guidelines (CPGs) in psychiatry, funded under the National Mental Health Strategy (Australia) and the New Zealand Health Funding Authority

METHOD

For these guidelines, the CPG team reviewed the treatment outcome literature (including meta-analyses) and consulted with practitioners and consumers.

TREATMENT RECOMMENDATIONS

This guideline provides evidence-based recommendations for the management of bipolar disorder by phase of illness, that is acute mania, mixed episodes and bipolar depression, and the prophylaxis of such episodes. It specifies the roles of various mood-stabilizing medications and of psychological treatments such as cognitive therapy and psycho-education.

Spotlight on lamotrigine in bipolar disorder

Lamotrigine (Lamictal), a phenyltriazine derivative, is a well established anticonvulsant agent that has shown efficacy in the prevention of mood episodes in adult patients with bipolar I disorder. The mechanism of action of the drug in patients with bipolar disorder may be related to the inhibition of sodium and calcium channels in presynaptic neurons and subsequent stabilisation of the neuronal membrane. Lamotrigine monotherapy significantly delayed time to intervention with additional pharmacotherapy or electroconvulsive therapy for any new mood episode (mania, hypomania, depression and mixed episodes), compared with placebo, in two large, randomised, double-blind trials of 18 months' duration. Additionally, lamotrigine was significantly superior to placebo at prolonging time to intervention for depression. These effects of lamotrigine were demonstrated in both recently manic/hypomanic and recently depressed patients. Lamotrigine showed efficacy in delaying manic/hypomanic episodes in pooled data only, although lithium was superior to lamotrigine on this measure. Two of four double-blind, short-term studies have shown lamotrigine to be more effective than placebo in the treatment of patients with treatment-refractory bipolar disorder or those with bipolar depression. Lamotrigine has not demonstrated efficacy in the treatment of acute mania. Lamotrigine was generally well tolerated in maintenance studies with the most common adverse events being headache, nausea, infection and insomnia. Incidences of diarrhoea and tremor were significantly lower in lamotrigine- than in lithium-treated patients. The incidence of serious rash with lamotrigine treatment was 0.1% in all studies of bipolar disorder and included one case of mild Stevens-Johnson syndrome. Lamotrigine did not appear to cause bodyweight gain. The dosage of lamotrigine is titrated over a 6-week period to 200 mg/day to minimise the incidence of serious rash. Adjustments to the initial and target dosages are required if coadministered with valproate semisodium or carbamazepine.

CONCLUSION

Lamotrigine has been shown to be an effective maintenance therapy for patients with bipolar I disorder, significantly delaying time to intervention for any mood episode. Additionally, lamotrigine significantly delayed time to intervention for a depressive episode and showed limited efficacy in delaying time to intervention for a manic/hypomanic episode, compared with placebo. Although not approved for the short-term treatment of mood episodes, lamotrigine has shown efficacy in the acute treatment of patients with bipolar depression but has not demonstrated efficacy in the treatment of acute mania. Lamotrigine is generally well tolerated, does not appear to cause bodyweight gain and, unlike lithium, generally does not require monitoring of serum levels.

Safety and Tolerability of Lamotrigine for Bipolar Disorder

Tolerability and safety are important considerations in optimising pharmacotherapy for bipolar disorder. This paper reviews the tolerability and safety of lamotrigine, an anticonvulsant recommended in the 2002 American Psychiatric Association guidelines as a first-line treatment for acute depression in bipolar disorder and one of several options for maintenance therapy. This paper reviews the tolerability and safety of lamotrigine using data available from a large programme of eight placebo-controlled clinical trials of lamotrigine enrolling a total of nearly 1800 patients with bipolar disorder. This review is the first to collate all the safety information from these clinical trials, including data from four unpublished studies. The results these trials in which 827 patients with bipolar disorder were given lamotrigine as monotherapy or adjunctive therapy for up to 18 months for a total of 280 patient-years of exposure demonstrated that lamotrigine is well-tolerated with an adverse-event profile generally comparable with that of placebo. The most common adverse event with lamotrigine was headache. Lamotrigine did not appear to destabilise mood and was not associated with sexual adverse effects, weight gain, or withdrawal symptoms. Few patients experienced serious adverse events with lamotrigine, and the incidence of withdrawals because of adverse events was low. Serious rash occurred rarely (0.1% incidence) in the clinical development programme including both controlled and uncontrolled clinical trials. These findings - considered in the context of data showing lamotrigine to be effective for bipolar depression - establish lamotrigine as a well-tolerated addition to the psychotropic armamentarium.

Antisuicide properties of psychotropic drugs: a critical review

The authors consider the extent to which psychotropic medications demonstrate benefits in the prevention of suicidal behavior in psychiatric patients. Results of a MedLine search are critically reviewed for lithium, divalproex and other anticonvulsants, conventional and atypical antipsychotics, and antidepressants. The existing literature is almost entirely limited to noncontrolled, often retrospective studies that do not control for potential biases in treatment selection, the use of multiple medications, the impact of medication nonadherence, and nonrandomized treatment discontinuations. Nevertheless, an extensive literature has arisen regarding observed reductions in suicidal behavior with lithium for mood disorders and, to a lesser extent, with clozapine for schizophrenia. A substantially smaller literature suggests more negative than positive data with divalproex or carbamazepine in bipolar disorder, while minimal information exists regarding suicidality with atypical antipsychotics other than clozapine. Studies of antidepressants have mostly been short-term and have focused more on whether they induce (rather than ameliorate) suicidal thoughts or behaviors. The sum of existing studies is generally inconclusive about whether antidepressants appreciably reduce risk for suicide completions. Relatively little is known about pharmacotherapy effects on suicidal ideation as distinct from behaviors. Possible mechanistic considerations for understanding antisuicide properties include a therapeutic impact on depression, impulsivity, or aggression, potentially mediated through serotonergic or other neuromodulatory systems. Recommendations are provided to guide future research as well as clinical practice.

Antidepressants in bipolar disorder: the case for caution

The 2002 American Psychiatric Association (APA) guidelines for the treatment of bipolar disorder recommended more conservative use of antidepressants. This change in comparison with previous APA guidelines has been criticized, especially from some groups in Europe. The Munich group in particular has published a critique of assumptions underlying the conservative recommendations of the recent APA treatment guidelines. In this paper, we re-examine the argument put forward by the Munich group, and we demonstrate that indeed, conceptually and empirically, there is a strong rationale for a cautious approach to antidepressant use in bipolar disorder, consistent with, and perhaps even more strongly than, the APA guidelines. This rationale is based on support for the following four propositions: (i) The risk of antidepressant induced mood-cycling is high, (ii) Antidepressants have not been shown to definitively prevent completed suicides and reduce mortality, whereas lithium has, (iii) Antidepressants have not been shown to be more effective than mood stabilizers in acute bipolar depression and have been shown to be less effective than mood stabilizers in preventing depressive relapse in bipolar disorder and (iv) Mood stabilizers, especially lithium and lamotrigine, have been shown to be effective in acute and prophylactic treatment of bipolar depressive episodes. We therefore draw three conclusions from this interpretation of the evidence: (i) There are significant risks of mania and long-term worsening of bipolar illness with antidepressants, (ii) Antidepressants should generally be reserved for severe cases of acute bipolar depression and not routinely used in mild to moderate cases and (iii) Antidepressants should be discontinued after recovery from the depressive episode, and maintained only in those who repeatedly relapse after antidepressant discontinuation (a minority we judge to represent only about 15-20% of bipolar depressed patients).

Clinical consequences of under-recognized bipolar spectrum disorder

The prevalence of bipolar disorder is higher than previously believed, especially when bipolar spectrum disorders (BSD) are taken into account, and may approach rates as high as 5%. Difficulties in diagnosing bipolar II and BSD arise from complexities associated with defining and diagnosing hypomania. Additionally, bipolar disorder and BSD are often misdiagnosed because of symptoms that overlap with other psychiatric disorders, particularly unipolar depression. Recognition of the broader spectrum of bipolar disorders and their adequate treatment is paramount because bipolar disorder exacts such a high personal and societal toll, with high rates of suicide and interpersonal problems and a substantial economic burden. Recognition can be improved with active screening, and screening tools such as the Mood Disorders Questionnaire can be easily included in the initial assessment of patients who present with depressive symptoms. Depressive episodes are common in patients who experience BSDs, and increasingly treatment approaches designed specifically for bipolar depression are being studied.

A re-evaluation of the role of antidepressants in the treatment of bipolar depression: data from the Stanley Foundation Bipolar Network

OBJECTIVES

The risk-to-benefit ratio of the use of unimodal antidepressants (ADs) as adjuncts to mood stabilizers continues to be an area of controversy and disagreement among experts in the field. This paper reviews new data on: (1) depression in bipolar illness, (2) switch rates on ADs and (3) risks of AD discontinuation that are pertinent to the ongoing discussion and recommendations.

METHODS

In the first study reviewed, 258 outpatients with bipolar illness were assessed prospectively on a daily basis using the National Institute of Mental Health-Life Chart Method (NIMH-LCM) for 1 year. In the second study, 127 bipolar depressed patients were randomized to 10 weeks of sertraline, bupropion, or venlafaxine, as adjuncts to mood stabilizers; non-responders were re-randomized and responders were offered a year of continuation treatment. In the final study, Altshuler et al. retrospectively and prospectively assessed the risk of depressive relapses in patients who remained on ADs after 2 months of euthymia compared with those who discontinued ADs.

RESULTS

Despite intensive naturalistic treatment, the 258 outpatients with bipolar illness followed prospectively for 1 year showed three times as many days depressed as days manic, re-emphasizing the considerable depressive morbidity that remains in bipolar disorder despite the number of treatment options available. In the study of bipolar depressed patients randomized to one of three ADs, a range of severities and durations of hypomanic to manic switches were discerned following 175 trials of AD augmentation of treatment with a mood stabilizer. Of the acute 10-week trials, 9.1% were associated with switches into hypomania or mania and another 9.1% with a week or more of hypomania alone (with no to minimal dysfunction). In 73 continuation phase AD trials, 16.4 and 19.2% were similarly associated with hypomanic to manic and hypomanic switches, respectively. In the Altshuler et al. studies, those who remained well on any AD for more than 2 months (only 15-20% of those initially treated) and who continued on ADs showed a lesser rate of relapse into depression over 1 year (35 and 36% in the first and second study, respectively) compared with those who discontinued their ADs (68 and 70% relapsing into depression). Surprisingly, this continuation of ADs was associated with no increase in the rate of switching into mania compared with those stopping ADs.

CONCLUSIONS

These data reveal that depression and depressive cycling remain a substantial problem in some two-thirds of intensively treated bipolar outpatients. Acute AD augmentation was associated with a modest response rate and 18.2% switched into a hypomanic to manic episode, and 35.6% of the continuation trials showed these two types of switches. Two separate studies suggest that in the very small subgroup who remain well on ADs for at least 2 months, one should consider continuation of this AD augmentation treatment, because AD discontinuation appears associated with a substantially increased risk of depression relapse over the subsequent year with no reduced risk of switching into mania.

Issues in the treatment of bipolar disorder

Bipolar disorder is a chronic, recurring illness that requires long-term prophylactic treatment. However, treatment is often complicated by misdiagnosis and inappropriate medication selection. A number of therapies are available for the treatment of bipolar disorder and the ultimate therapeutic choice depends on the individual patient's current symptoms, disease history, and comorbid illnesses. However, research is needed to improve the overall prognosis for patients with bipolar depression, particularly because approximately 20% of patients commit suicide. Mania is the most dramatic expression of bipolar disorder and may overshadow the impact of the depressive phase of the illness. Compared with mania, episodes of bipolar depression are more frequent, of longer duration, and are associated with higher rates of morbidity and mortality. Therefore, successful treatment and prevention of bipolar depression remains an essential treatment goal.

Latest maintenance data on lithium in bipolar disorder

Although lithium is generally considered to be the gold standard for maintenance therapy in bipolar disorder, evidence of its efficacy has rested on only a small number of adequately designed studies. Results from the lamotrigine bipolar trials, which included lithium as an active comparator, will substantially increase confidence in long-term lithium treatment. In a meta-analysis of these data, lithium was significantly more effective than placebo in preventing relapse in patients with bipolar disorder (relative risk [RR] 0.65; 95% confidence interval [CI] 0.50, 0.84). Furthermore, lithium had significant efficacy against manic relapse (RR 0.61; 95% CI 0.39, 0.95), with a less substantial, not statistically significant, effect against depressive relapse (RR 0.72; 95% CI 0.49, 1.07). Factors such as disease subtype, likelihood of adherence to treatment regimen, tolerability, and dose uncertainty should be considered in the selection of lithium maintenance therapy.

Latest maintenance data on lamotrigine in bipolar disorder

Two 18-month, randomised, double-blind trials have compared lamotrigine, lithium, and placebo as maintenance treatment in a total of 1315 recently manic or depressed patients with bipolar I disorder. Individual and combined analyses of these studies showed that both lamotrigine and lithium significantly prolonged the time to intervention for any mood episode compared with placebo. Lamotrigine was primarily effective against depression and lithium was primarily effective against mania. There was no evidence that lamotrigine induced mania/hypomania/mixed states, caused episode acceleration, or destabilised the overall course of illness. Lamotrigine was well tolerated, with a placebo-like adverse-event profile. In summary, lamotrigine is an effective and well-tolerated maintenance treatment for bipolar I disorder, providing a spectrum of efficacy complementary to that of lithium.