Rapid cycling bipolar disorder

Rapid cycling bipolar disorder (RCBD) is defined in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) as a type of manic-depressive illness in which the patient experiences four or more episodes of mania and/or major depression per year. It was first reported as a consequence of the reduced effectiveness of lithium carbonate in the treatment and prophylaxis of this form of bipolar disorder (BD) in contrast to those with less frequent cycling. Among the anticonvulsants, there have been reports with different degrees of controlled data concerning carbamazepine, valproate, lamotrigine, topiramate, gabapentin and primidone. There is a paucity of double-blind studies, but what is available supports the use of lamotrigine. There is open data supporting the use of carbamazepine, valproate and topiramate. Regarding other classes, nimodipine may have specific utility in ultradian- (ultra-ultra-) or ultra-RCBD and there is double-blind data regarding the specific utility of olanzapine in RCBD. Low thyroid function may be a factor in development of RCBD; therapies aimed at elevating thyroid levels, even beyond the usual range, have frequently produced benefits in open trials. More research is needed into the possible therapeutic benefits of verapamil, bupropion, choline, light therapy and electroconvulsive therapy (ECT).

Antipsychotic medication: effects on regulation of glucose and lipids

Since the introduction of chlorpromazine in the 1950s, antipsychotics have been used for the treatment of schizophrenia. The phenothiazines were followed by the butyrophenones, particularly haloperidol. With all the movement disorder side effects of these medications (extrapyramidal syndrome, akathisia, tardive dyskinesia), the pharmaceutical industry has gradually released atypical antipsychotics. This class includes clozapine (released in the USA in 1990), risperidone (1994), olanzapine (1996), quetiapine (1998) and ziprasidone (2001). However, the rate of diabetes mellitus in patients with schizophrenia appeared to increase with the availability of this class of medications. In reviewing rate and degree of changes in weight, glucose control and lipid levels induced by typical and atypical antipsychotics, it was found that in contrast to case reports, there is a dearth of retrospective, open and controlled studies. However, in studies as early as 1964, significant weight increases were found to be associated with use of chlorpromazine. While the phenothiazines may have some effect on patients with chemical diabetes, there is little evidence of the typical antipsychotics producing diabetes mellitus de novo, or worsening diabetes that is already been discovered. Ziprasidone appears to be the antipsychotic with the most beneficial combination of effects: no weight gain, no change in glucose utilisation and reductions in cholesterol and serum triglycerides (TGs).

Ziprasidone: profile on safety

Ziprasidone (Geodon, Pfizer) is the latest of a new class of atypical antipsychotics, following the release of clozapine, risperidone, olanzapine and quetiapine. It has a serotonin Type 2a/dopamine Type 2 (5-HT2a/D2) receptor (R) binding ratio of approximately 8:1; amongst the highest of its class. Furthermore, it is a potent 5-HT1aR agonist, and displays 5-HT1dR and 5-HT2cR antagonist activity, with unique effects on blocking the re-uptake of both 5-HT and noradrenaline (NE). Finally, ziprasidone has low-to-modest affinity for histamine (H1) and alpha 1-adrenoceptors and a negligible affinity for muscarinic (M1) Rs. This combination of effects may be responsible for its low rate of general adverse events, low rate of persistent prolactin elevation, low incidence of weight gain, low liability for inducing movement disorders, low rate of syncope and induction of decreases in lipid profile. Data on the effect of ziprasidone on the electrocardiogram (ECG) indicates a relatively higher degree of change in measure of QTc but no cases of mortality from overdoses, torsade de pointes (TdP) or excess in sudden and unexpected deaths.

Vagus nerve stimulation in depression

Ever since the introduction of chemical and electrical convulsive treatment for psychiatric disorders in the 1930s and 1940s, biological techniques have been used extensively in the amelioration of a variety of psychiatric disorders. Techniques of recent vintage have included transcranial magnetic stimulation, deep brain stimulation and vagus nerve stimulation (VNS). Since VNS attenuates seizures in animal models, the treatment was initially developed and approved by the FDA for treatment of drug-resistant partial-onset epilepsy. Additional data, including the known neuroanatomy of the vagus nerve, effects of VNS on monoamines and mood improvement in patients with epilepsy who were treated with VNS, provided a rationale for further investigation in patients with primary mood disorders. VNS has been administered acutely for 10 weeks to 60 patients with treatment-resistant depression. Longer-term follow-up data has been analysed for the first 30 patients. Response rates have been at least 30% in the acute study. Similar to findings in epilepsy and in contrast to the usual results of long-term medication trials, longer term data regarding symptomatic and functional outcomes of depressed patients receiving VNS continue to look promising. As opposed to electroconvulsive therapy, VNS is not associated with cognitive impairment. These results have led to approval of VNS for the treatment of resistant depression (unipolar or bipolar) in both Europe and Canada. Currently, a pivotal double-blind acute study is underway in the US.

Use of olanzapine in non-psychotic psychiatric disorders

The history of antipsychotic medications begins in the 1950s with chlorpromazine, developed originally as an antihistamine but found to be an aid in the reduction of symptoms of delusions and hallucinations. This phenothiazine derivative was followed by numerous others in the same class (e.g., thioridazine) and then by antipsychotics in other classes (e.g., the popular haloperidol of the butyrophenone class). This group of medications is associated with a number of unpleasant side effects and complications. These included extrapyramidal symptoms (EPS), orthostatic hypotension, hyperprolactinemia and last, but certainly not least, tardive dyskinesia (TD). As a consequence, other alternative antipsychotics were developed in which D(2) blockade effect generally associated with EPS and TD was offset by 5-HT(2) antagonism. The first of this class was clozapine; however, it is associated with agranulocytopenia of sudden onset as well as seizure induction. However, olanzapine, a close structural relative, was soon synthesised for treatment of psychosis and particularly schizophrenia (Zyprexatrade mark, Eli Lilly). It was released in the US in November 1996 with FDA approval for that indication. However, antipsychotics have always been used for other psychiatric disorders, aside from schizophrenia. This includes, in particular, mania, where chlorpromazine use predated lithium as an effective treatment. Other uses for antipsychotics have included other mood disorders, dementia, childhood disorders and personality problems. Here, information on the application of olanzapine to non-schizophrenic disorders is reviewed. Despite the fact that the research post-dates FDA approval in 1996, there was already sufficient evidence for olanzapine's effectiveness in acute mania to obtain approval from the US FDA in March 2000. Other research supports its use as adjunctive therapy in depressive disorders. Phase IV studies and case reports have found limited support for olanzapine's use in a variety of other psychiatric disorders, behavioural disorders of dementia (including Alzheimer's disease), pervasive developmental disorder of childhood, obsessive-compulsive disorder and borderline personality disorder. In each of these latter diagnoses, double-blind studies are either underway or are planned to establish efficacy.

Use of antidepressants in treatment of comorbid diabetes mellitus and depression as well as in diabetic neuropathy

After a brief review of epidemiology, the focus is on biochemistry of diabetes. Animal and human studies are reviewed in terms of the impact of alterations in catecholamines and serotonin (5-hydroxytryptamine, 5HT) on glucose utilization. Then, the implications of these experimental results for the choice of antidepressant in comorbid diabetes mellitus and depression as well as in diabetic neuropathy are discussed. Results of clinical investigations are then reviewed in terms of the above hypotheses. An Index Medicus Search for the past 10 years was supplemented by references from previous related reviews of the topic as well as by pending results, where available, not previously published. The range of prevalence of depression in diabetic patients has been 8-27%, depending on study criteria and procedures. An increase of catecholamines appears to increase glucose while both reducing insulin release and reducing sensitivity to insulin that is available. In contrast, increases in serotonergic function by increased precursor, increased release, or blocked metabolism and blocked reuptake in contrast seem to increase sensitivity to insulin and reduce plasma glucose. There have been six studies of fluoxetine, a selective serotonin reuptake inhibitor (SSRI), at a dose of 60 mg/day pursued up to 12 months that have demonstrated that medication's usefulness in diabetic patients, with reductions in weight (to 9.3 kg), in FPG (to 45 mg%), and in HbA1c (to 2.5%). In studies in comorbid diabetes mellitus and depression, nortriptyline, a norepinephrine reuptake inhibitor that produces increased synaptic catechols, has led to worsening of indices of glucose control. However, fluoxetine and sertraline, both selective serotonin reuptake inhibitors, in the same patient group, have produced results consistent with reductions in glucose levels. In diabetic neuropathy, perhaps due to the fact that catecholamines and serotonin may both be implicated in pain pathways, dual-action antidepressants appear more effective at lower doses than do specific serotonergic agents. The tricyclic antidepressants (TCA) (66.7%) have had success in double-blind studies, particularly imipramine, with a 81% response rate. Yet, there are positive reports concerning the SSRIs (paroxetine, citalopram, sertraline), as well as nefazodone, that focus on serotonin selectivity.

CONCLUSIONS

In comorbid diabetes mellitus and depression, most evidence supports the use of fluoxetine in control of glucose handling. Other characteristics in terms dosing, drug interactions, cognition, and sleep make sertraline an attractive alternative agent. In diabetic neuropathy without depression, the best choices among non-TCAs may include sertraline, citalopram, and perhaps, venlafaxine, since the TCAs appear to increase cravings and increase FBG levels.

Treatment of depression in comorbid medical illness

The rate of comorbid depression and medical illness varies from 10 to 40%. Over the years, there has been a paucity of studies completed despite the importance of knowing which antidepressants are the most effective and safest to use in comorbid states. In this review, focus is placed on disorders in these important areas: cardiovascular disease, neurological disorders, diabetes mellitus and cancer. Cardiovascular disease complications can be related in many cases to platelet clumping produced by medications; reductions in morbidity can be achieved by reducing platelet adhesiveness. Specific results have shown sertraline administration to be safe in the post myocardial infarction (MI) state. This is a time of depression-induced increases of 200-300% in mortality. Evidence for safe administration of bupropion, as well as the selective serotonin re-uptake inhibitors (SSRIs) fluoxetine and paroxetine, is also available. The appearance of major depression and diabetes mellitus has been successfully treated with fluoxetine, sertraline and nortriptyline (NTI), however, NTI may lead to a worsening of glucose indices due to its noradrenergic specificity. Regarding neurologic disorders, there is controlled data showing the safety and efficacy of citalopram, sertraline and fluoxetine in post stroke depression. Parkinson's disease has been associated frequently with depression, as might be expected from its characteristic dopamine deficient state. For perhaps the same reason, the agents that can block re-uptake of dopamine i.e., tricyclic antidepressants (TCAs), have been effective in comorborbid depression with Parkinson's disease. In dementia, there is a paucity of information on new agents. However, double-blind data seems to show efficacy for sertraline, paroxetine and citalopram. There are few studies of cancer-related depression treated in a controlled fashion with antidepressants; imipramine, amitriptyline, fluoxetine, paroxetine, mirtazapine and mianserin (not available in the USA) all have support from some published studies.

The use of nimodipine in the treatment of mood disorders

Nimodipine, a dihydropyridine calcium entry blocker, has been shown to protect from neuronal damage due to ischemia by providing for increased postischemic perfusion. Further, it has also been demonstrated to have antiepileptic properties. These two properties--calcium channel blockade and anticonvulsant benefits have been applied with success to mood disorder treatment. Although found helpful nearly a decade ago for uncomplicated mania, nimodipine may have particular benefits for those diagnostic subclasses of bipolar disorder most resistant to therapy, e.g., ultra-rapid-cycling bipolars and brief recurrent depressions.

Summary from the 153rd meeting of the American Psychiatric Association. 13-18 May 2000, Chicago, Illinois, USA

The annual meeting of the American Psychiatric Association focuses on a variety of topics, including those on psychopharmacology. The latest developments are typically those found in the New Research sections, which is where this summary will focus.

Women's issues in mood disorders

Since the introduction of antidepressants in the 1950s, it was assumed for the next several decades that there were no special reasons to look at the application of these medications to women. In the past half-century, particularly in the past decade, since the advent of the selective serotonin re-uptake inhibitors (SSRI), a series of specific foci have developed. Firstly, there appear to be differences in the degree of response to particular antidepressants between the genders. Secondly, there is data concerning hormonal effects of particular relevance to women, i.e. prolactin, which separates out among the antidepressants. Also of concern to women are the potential teratogenic effects of these medications, which impact on their use during pregnancy. Finally, there are certain diagnostic syndromes that are particularly relevant to women: premenstrual dysphoric disorder (PMDD); postpartum depression (PPD) and perimenopausal depression (PMD). It appears that the SSRIs may be more effective, relative to the older tricyclic antidepressants (TCA), in women than in men. The SSRIs have shown to be effective in treating these disorders, with the possibility of intermittent luteal phase treatment of PMDD. Non-antidepressant (AD) approaches have generally been found to be less effective. In the first trimester of pregnancy, there is data available supporting the safe use of SSRIs, particularly those first released, i.e. fluoxetine and sertraline. Finally, all SSRIs, with the exception of sertraline, can increase the risk of hyperprolactinaemia. This can lead to a variety of complications including amenorrhea and osteoporosis. This effect of sertraline, due to its unique profile in blocking re-uptake of dopamine, extends itself into additional relative benefits for sleep and memory. The issues associated for women with bipolar disorder are dealt with in terms of both increased risk of relapse during pregnancy and postpartum periods, as well as the relative risk of use of lithium and mood stabilizers in pregnancy and lactation.

Nefazodone treatment of adolescent depression: an open-label study of response and biochemistry

OBJECTIVE

The purpose of this study was to find whether nefazodone, effective in adult depression, might be similarly improve symptoms of adolescent depression. Secondary purpose was to relate platelet serotonin content to response, and to find if nefazodone's effect on platelet content was similar to that of the SSRIs.

METHOD

10 adolescents meeting DSMIV criteria for major depression received up to 400 mg of nefazodone for an eight week period. Response was assessed at baseline, 1, 2, 4, and 8 weeks by BDI and HDRS; platelet serotonin (5HT) content was obtained at baseline and final visit (for two dropouts, this was done at last visit, i.e., week 4).

RESULTS

In LOCF analysis, significant improvement was found in both HDRS (20.9 to 8.9, p = .01) and BDI (24.6 to 10.2, p = .01). Eight of nine patients with available data showed increases in platelet 5HT content (.02). In seven patients of eight completers with available data, there was a nonsignificant trend for patients with platelet 5HT baseline greater than 30 ng/10(8) platelets to show a greater change in HDRS than those with a baseline of less than 30 ng/10(8) platelets (p = .07).

CONCLUSIONS

Further double-blind study of nefazodone in adolescent depression is indicated; nefazodone appears to increase platelet 5HT content.

Mirtazapine in major depression with comorbid generalized anxiety disorder

BACKGROUND

A high proportion of patients with generalized anxiety disorder (GAD) have comorbid depressive illness. The presence of anxiety in depression has significant prognostic implications. Because of mirtazapine's early anxiolytic effects, the present study was undertaken as a preliminary investigation in patients with a diagnosis of major depression with comorbid GAD.

METHOD

Mirtazapine was administered to 10 patients with DSM-IV major depressive disorder and comorbid GAD in an 8-week open-label study. Mirtazapine was increased from an initial daily dose of 15 mg to a maximum daily dose of 45 mg.

RESULTS

Patients were found to have significant reductions in Hamilton Rating Scale for Depression scores, Hamilton Rating Scale for Anxiety scores, and Beck Depression Inventory scores, with improvement noted after the first week of therapy and continuing improvement over the 8 weeks of study.

CONCLUSION

These positive preliminary findings support the further investigation of mirtazapine's potential value as a treatment for generalized anxiety disorder in addition to its established efficacy as an antidepressant drug.

Selective serotonin reuptake inhibitors in affective disorders--I. Basic pharmacology

The selective serotonin reuptake inhibitors (SSRIs), citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline, are the result of rational research to find drugs that were as effective as the tricyclic antidepressants but with fewer safety and tolerability problems. The SSRIs selectively and powerfully inhibit serotonin reuptake and result in a potentiation of serotonergic neurotransmission. The property of potent serotonin reuptake appears to give a broad spectrum of therapeutic activity in depression, anxiety, obsessional and impulse control disorders. However, despite the sharing of the same principal mechanism of action, SSRIs are structurally diverse with clear variations in their pharmacodynamic and pharmacokinetic profiles. The potency for serotonin reuptake inhibition varies amongst this group, as does the selectivity for serotonin relative to noradrenaline and dopamine reuptake inhibition. The relative potency of sertraline for dopamine reuptake inhibition differentiates it pharmacologically from other SSRIs. Affinity for neuroreceptors, such as sigma1, muscarinic and 5-HT2c, also differs widely. Furthermore, the inhibition of nitric oxide synthetase by paroxetine, and possibly other SSRIs, may have significant pharmacodynamic effects. Citalopram and fluoxetine are racemic mixtures of different chiral forms that possess varying pharmacokinetic and pharmacological profiles. Fluoxetine has a long acting and pharmacologically active metabolite. There are important clinical differences among the SSRIs in their pharmacokinetic characteristics. These include differences in their half-lives, linear versus non-linear pharmacokinetics, effect of age on their clearance and their potential to inhibit drug metabolising cytochrome P450 (CYP) isoenzymes. These pharmacological and pharmacokinetic differences underly the increasingly apparent important clinical differences amongst the SSRIs.

Selective serotonin reuptake inhibitors in affective disorders--II. Efficacy and quality of life

Since their introduction, the selective serotonin reuptake inhibitors (SSRIs) have become one of the most widely used classes of medication in psychiatry. Their popularity is based on apparent efficacy over a wide range of disorders and a favorable side-effect profile. However, as with any psychotropic medication, considerable data are required to define where a drug works and where it does not. There is now a wealth of evidence demonstrating that SSRIs may differ in their efficacy profiles in certain depressive symptoms, in different subtypes of depression, with respect to their ability to maintain efficacy over time, on broader outcomes such as quality of life, and in the consistency of the usually effective minimum therapeutic dose across the age spectrum and across indications. Although this review includes data on all SSRIs, it focuses on fluoxetine and sertraline, which in addition to being the most widely used SSRIs are also the most widely studied. The relative quantity and quality of data on these two SSRIs means that it is possible to make relatively firm inferences regarding their differential effects on affective symptoms and quality of life.

Selective serotonin reuptake inhibitors in the treatment of affective disorders--III. Tolerability, safety and pharmacoeconomics

The clinical use of tricyclic antidepressants (TCAs) is often complicated by toxicity and safety problems due to their effects on multiple mechanisms of action, many of which are unnecessary for therapeutic effect. The development of the selective serotonin reuptake inhibitors (SSRIs), with their selective mode of action, has resulted in a class of antidepressant drugs possessing an improved side-effect profile, while retaining good clinical efficacy. Their introduction into clinical practice has led to enhanced patient compliance with antidepressant therapy and the ability to maintain treatment over longer periods of time at an adequate therapeutic dose. Although, as a result of their selective action, side-effects associated with SSRI therapy are minimised, distinct variations between individual SSRIs in terms of their tolerability profiles have been observed. The wealth of clinical data now available has revealed differences in their potential to cause psychiatric and neurological side-effects, dermatological reactions, anticholinergic side-effects, changes in body weight, sexual dysfunction, cognitive impairment, discontinuation reactions and drug-drug interactions. Patients who suffer from concomitant depression and physical illness may experience different tolerability profiles, in addition to the greater likelihood that they will be receiving concomitant medications with the potential for pharmacokinetic drug-drug interactions with coadministered SSRI therapy. In addition, the safety margin of SSRIs in overdose may vary within the group. Knowledge of the differences that exist among the SSRIs in respect of tolerability and safety will aid physicians in the selection of the most beneficial treatment strategy for their patients. A successful clinical outcome leads to a reduced economic burden for the patient, their family and the healthcare services. Thus, pharmacoeconomic considerations are also important in choosing antidepressant therapy. The SSRIs, despite relatively higher prescription costs, have been demonstrated to be a more cost-effective option than the TCAs. Furthermore, there is evidence that the emerging clinical differences between SSRIs may translate into significantly different economic outcomes within the group.

Bupropion slow-release response in depression: diagnosis and biochemistry

BACKGROUND

Bupropion has been previously shown to be particularly beneficial in bipolar and atypical depression. Previous research has supported a possible association of response to plasma levels and to changes in plasma homovanillic acid (HVA). These findings were here extended to bupropion slow-release (SR), a formulation with slower release kinetics.

METHODS

Forty-one patients with major depressive disorder (DSM-III-R) completed 8 weeks of a fixed dose of 300 mg/day in two doses/day. Clinical outcome measures were the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI). Biological parameters included plasma HVA and 3-methoxy-4-hydroxyphenyl-glycol (MHPG), as well as a final measurement of plasma bupropion and its metabolites.

RESULTS

Response to bupropion SR differed among the three groups: results for change in HDRS and in BDI were greater in the bipolar and atypical than in the "typical" depressed patients. Mean change in HDRS was, respectively, of 15.6, 17.1, and 7.6 (F = 5.57, p < .01); mean change in the BDI, 21.1, 16.9, and 7.3 (F = 3.32, p < .05). Threobupropion levels correlated with HDRS scores (r = .47, p = .02, n = 23); plasma HVA and MHPG increased significantly (t = 2.31, p = .03; t = 2.15, p = .04, n = 17). Bipolar depressed patients' improvement in HDRS was related to increases in MHPG (r = .87, p = .01) and in HVA (r = .70, p = .08).

CONCLUSIONS

This fixed-dose study indicates that there may be specific benefits for bupropion SR in atypical and bipolar depression, and that these benefits may be related also to plasma levels and biochemical changes in catecholamines. Due to the small sample size, replication is of key importance.

Sertraline in diabetic neuropathy: preliminary results

Previous research has shown that antidepressants have been useful in the treatment of pain, particularly diabetic neuropathy. This study was an initial open investigation into the use of sertraline in diabetic neuropathy. Eight patients with diabetic neuropathy but not depression were treated with increasing doses of sertraline to a maximum of 150 mg/day for 8 weeks. Sertraline treatment led to significant reductions in mean visual analog scale (VAS) ratings, e.g., pain from 71.2 to 23.1 (t = 3.74, p < .01) and paresthesias from 53.8 to 15.0 (t = 4.15, p < .01). Baseline platelet serotonin (5HT) content also correlated significantly with improvement in pain (r = 0.70,p =. 05). Plasma sertraline (SRT) correlated with improvement in paresthesias (r = 0.70).

CONCLUSION

This preliminary result indicates the potential application of sertraline to treatment of diabetic neuropathy. A replication is now underway.

Sertraline in coexisting major depression and diabetes mellitus

As many as 25 percent of patients with diabetes mellitus may also have depressive symptoms. Tricyclic antidepressants (TCAs) may produce increased appetite and weight gain with adverse consequences for diabetes. The selective serotonin reuptake inhibitors (SSRIs), however, may improve fasting blood sugar in laboratory studies. In an initial application, sertraline was administered at a dose of 50 mg/day in a 10-week open study to 28 non-insulin-dependent diabetes mellitus (NIDDM) patients with DSM-III-R major depression after a 2-week single-blind placebo washout period with a minimum 17-Item Hamilton Rating Scale for Depression (HAM-D) score of 18. The patient group included 16 males and 12 females with a mean age of 54.2 +/- 8.8 years. Results indicated (1) significant improvement in mean HAM-D (22.6 +/- 3.4 to 4.9 +/- 5.9, p < .001) and in mean Beck Depression Inventory (BDI) scores (21.9 +/- 10.5 to 12.7 +/- 8.3, p < .001); (2) fall in platelet serotonin (5-HT) content (79.7 +/- 22.5 to 13.6 +/- 12.7 ng/10(8) platelets, p < .001); (3) correlation of baseline platelet 5-HT content with response to sertraline by BDI scores (r = 0.51, p < .05); (4) improved dietary compliance for those with baseline value below 70 percent (59.7% to 69.1%, p < .005); and (5) 13 of 17 patients with baseline glycosylated hemoglobin A (HbA1c) levels greater than 8.0, showed a reduction (p = .018). Sertraline may be an effective antidepressant in patients with diabetes mellitus and response may be predictable by higher baseline platelet 5-HT content, with the potential to improve dietary compliance and reduce HbA1c measures. As with all open studies, replication is essential.

Treatment of mania: relationship between response to verapamil and changes in plasma calcium and magnesium levels

Twelve patients meeting DSM-IIIR criteria for mania received verapamil over a 2-week period, with dosing up to 360 mg/day. Severity of mania was measured at baseline and weekly by use of the Young Mania Scale. Plasma calcium and magnesium determinations and an ECG were obtained at baseline and after 2 weeks of treatment. Mean improvement was from a baseline of 32.4 to 12.8, -60.5%. Decreased severity of mania correlated significantly with increased plasma calcium. This result may lend a method for monitoring successful treatment of mania with calcium channel inhibitors.

Adverse events after the abrupt discontinuation of paroxetine

Paroxetine is an antidepressant of the selective serotonin reuptake inhibitor (SSRI) class. In contrast to other SSRIs, it has a relatively short half-life and lacks active metabolites. In three patients the abrupt discontinuation of paroxetine seemed associated with sudden and impairing effects. All three reported marked sleep disturbances and dizziness. They were prescribed the drug for a minimum of 10 weeks, and the maximum dosage was 40 mg/day. All patients experienced rapid remission of symptoms after paroxetine was reintroduced. We failed to observe similar reactions from the abrupt discontinuation at lower dosages. Gradual tapering of the agent for patients receiving more than 20 mg/day is recommended.

Treatment of depression in patients with diabetes mellitus

BACKGROUND

Depression occurs frequently in patients with diabetes mellitus. Little has been published on the epidemiology, biochemistry, and treatment of depression in diabetic patients.

METHOD

We searched MEDLINE for literature from January 1966 to July 1993 and cross-referenced the terms diabetes, glucose, hyperglycemia, or hypoglycemia, with each of the following: antidepressants, monoamine oxidase inhibitors, tricyclic antidepressants, fluoxetine, paroxetine, sertraline, and bupropion. The results reviewed were 20 papers on epidemiology, 15 papers on neurochemicals and glucose control, and 28 papers on antidepressants and factors of importance to diabetics. Additional papers were selected from the reference lists of the retrieved articles.

RESULTS

The prevalence of depression in diabetics varies from 8.5% to 27.3%. Severity of depression correlates strongly with many symptoms of diabetes mellitus. The hydrazine monoamine oxidase inhibitors (MAOIs), e.g., phenelzine, potentiate animal models of hypoglycemia due to direct influence on gluconeogenesis secondary to the hydrazine structure, not to MAOI considerations. Dopamine and norepinephrine influences in these models appear to be hyperglycemic. Serotonergic influences, in the presence of MAOIs, which decrease serotonin metabolism, are in contrast hypoglycemic. Clinically, MAOI use is limited by the possible severity of the induced hypoglycemia, induced weight gain, and required diets. The tricyclic antidepressants may lead to hyperglycemia, to an increase in carbohydrate craving (from 86% to 200%), and impaired memory. Serotonin selective reuptake inhibitors (SSRIs) may be hypoglycemic (causing as much as a 30% decrease in fasting plasma glucose) and anorectic (causing an approximately 2-lb decrease), while possibly improving alertness.

CONCLUSION

Depression is frequent among diabetic patients and impairs diabetic management. To maximize response of both depression and diabetic disorder, one should consider the SSRIs in preference over the TCAs.

Pharmacokinetic optimisation of therapy with newer antidepressants

Since the early 1950s, when imipramine was first introduced, a whole series of antidepressants with differences in structures, neurochemical effects and pharmacokinetics have been developed. Structurally or functionally, they have been classified as tricyclic antidepressants (TCAs), tetracyclic antidepressants, monoamine oxidase inhibitors (MAOIs), or selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs). In addition, there is a series of antidepressants with unique structures. Many of the newer TCAs appear to have shorter half-lives than the standard TCAs (e.g. imipramine), allowing for the possibility of a more rapid response, but requiring the drugs to be given in multiple daily doses, which may reduce patient compliance. The short time to peak plasma concentration (tmax) can also lead to rapid onset of adverse effects. The tetracyclic antidepressants have longer elimination half-lives (t1/2) than the TCAs, but there is only very minimal evidence for a relationship between drug concentrations in the blood and clinical response. The triazolopyridines, like the newer TCAs, show pharmacokinetic evidence for rapid onset of adverse effects and the need for multiple daily doses due to short tmax and t1/2. The newer MAOIs are a significant addition to therapy, as the rapid binding action of these medications increases their safety margin with regard to tyramine interactions. Further information in this area is required. In addition, moclobemide has pharmacokinetic features that are clinically beneficial (e.g. aging and renal dysfunction have little effect on the elimination of the drug), but also features that are not beneficial (e.g. nonlinear pharmacokinetics). Among the SSRIs, there are a range of t1/2 values for the parent drugs, from relatively short t1/2 values of less than 24 hours (paroxetine, fluvoxamine) to among the longest found (e.g. 2 days for fluoxetine). Only 2 of the agents (sertraline and citalopram) have linear pharmacokinetics, and 1 drug has nonlinear pharmacokinetics within the usual therapeutic range (fluvoxamine). Once a therapeutic blood concentration is established, linearity is helpful in avoiding the small dose changes and repeated rechecking of concentrations of medications that would be required for those agents with nonlinear pharmacokinetics. Sertraline stands out as having the best effects on behaviour among all antidepressants. However, fluoxetine and fluvoxamine are least likely to penetrate into breast milk. All 3 of the structurally unique newer antidepressants [amfebutamone (bupropion), viloxazine venlafaxine] have relatively short tmax values (1 to 2 hours), which may relate to the early onset of adverse effects. Amfebutamone has the benefits of linear pharmacokinetics with potential for defined therapeutic blood concentrations, lack of effect of liver enzymes on metabolism of the drug, and lack of significant effects of either aging or hepatic dysfunction on elimination of the drug. Thus, the antidepressants best suited for pharmacokinetic optimisation of therapy are the following: desipramine, sertraline, fluvoxamine, citalopram and amfebutamone.

Psychotropic treatment of chronic fatigue syndrome and related disorders

BACKGROUND

Chronic fatigue syndrome (CFS) and fibromyalgia frequently are associated with symptoms of major depression. For this reason, antidepressants have been used in treatment of these disorders; however, little direction has been provided into this application in psychopharmacology.

METHOD

First, nine studies were reviewed regarding the relationship of the symptoms of fatigue and depression. Next, 23 reports (12 double-blind studies, 7 open studies, and 4 case reports) were reviewed for the effectiveness of therapy as assessed by global response and improvement of both depression and pain. Studies were differentiated by type of controls, as well as by alleged mechanism of action of the pharmacologic agent.

RESULTS

Disturbances in brain neurochemistry shared by CFS and major depression may serve as a basis for the effectiveness of some antidepressants in CFS. Response to some antidepressants in patients with CFS or fibromyalgia may occur at doses lower than those used in major depression, e.g., amitriptyline 25-75 mg/day. We further found that the more serotonergic treatments (e.g., clomipramine) were more successful in alleviating pain than depression, whereas catecholaminergic agents (e.g., maprotiline, bupropion) seemed particularly effective for symptoms of associated depression.

CONCLUSION

To maximize response of the physiologic and psychological consequences of the disorder, more investigation is needed to replicate the apparent findings that relate the neurochemical impairment underlying CFS and fibromyalgia to the type of antidepressant mechanism.

Bupropion treatment of fluoxetine-resistant chronic fatigue syndrome

Chronic fatigue syndrome (CFS) includes many symptoms of major depression. For this reason, many antidepressants have been used to treat the symptoms of this disorder. Among the more recently released antidepressants are fluoxetine and bupropion. In this open study, nine CFS patients who either could not tolerate or did not respond to fluoxetine showed significant response when administered 300 mg/day of bupropion for an 8-week period in both rating of HDRS (t = 4.80, p < 0.01) and BDI (t = 2.48, p < 0.05). Furthermore, bupropion improvement in Hamilton Depression Rating Scale correlated significantly with change in plasma homovanillic acid (HVA) (r = 0.96, p < 0.01). Plasma total methylhydroxyphenolglycol (MHPG) also increased significantly during bupropion treatment (t = 2.37, p = 0.05). Measures of T1 microsomal antibodies also decreased over treatment time; increases in natural killer cell numbers correlated inversely with change in plasma levels of free MHPG (r = -0.88, p < 0.05). Bupropion responders were more likely to have trough blood levels above 30 ng/ml (chi 2 = 3.6, p = 0.05).

Blood levels and acute response to bupropion

Twenty-three patients with major depressive disorder were treated with bupropion in an open-design protocol. Fifteen (65.2%) of the 23 responded with a more than 50% decrease in scores on the Beck Depression Inventory. Patients with trough blood levels of 10-29 ng/ml had a significantly better response than those with trough levels of 30 ng/ml or more. This preliminary result warrants further, double-blind evaluation.

Calmodulin-activated calcium ATPase in bipolar illness

Calmodulin-activated calcium ATPase is a transport enzyme which establishes the normal level of intracellular ionized calcium in most cells. We have determined values for three parameters of this enzyme: E-t, the concentration in the membrane; Vmax, the maximal velocity, and Ka, the binding affinity for calmodulin. We assayed these parameters in erythrocyte membranes from lithium carbonate-treated bipolar subjects and from normal controls. Bipolar subjects have significantly increased levels of E-t compared with normal controls.

Inter-episode major and subclinical symptoms in affective disorder

A prospective 1-year study was conducted in 69 patients with affective disorder. Despite remission, there was a significant continued presence at each visit of major symptoms of mania and depression and of mean mood shift. Furthermore, sub-clinical affective symptoms, as determined by General Behavior Inventory self-rating scores completed at 4 month intervals, continued at a level throughout the entire year significantly higher in patients than in 14 normal controls. Finally, as expected, presence of subclinical symptoms on the GBI correlated significantly with presence of major symptoms and mood shift. Correlation varied from 0.55 to 0.61; all significances were less than 0.001.

Lithium level and inter-episode symptoms in affective disorder

Forty-two patients with a history of affective disorder on lithium prophylaxis alone participated in a prospective 1-year study of inter-episode symptoms. Despite expected significant differences in mean plasma lithium level in patients, those with mean levels above the median (0.82 +/- 0.10 mEq/l) did not differ in incidence of major symptoms per visit, in mood shift per visit, or in rate of subclinical symptoms on the General Behavior Inventory from those patients with mean level below the median (0.52 +/- 0.09 mEq/l).

Predictors of interepisode symptoms and relapse in affective disorder patients treated with lithium carbonate

For 98 affective disorder patients receiving lithium prophylaxis for a mean of 45 months, number of interepisode symptoms correlated with relapse rate. Response to prophylaxis appeared highly determined by prelithium frequency of episodes and duration of lithium treatment.

Pattern analysis of antidepressant response to fluoxetine

Seventy patients with unipolar major depressive disorder were treated with fluoxetine or placebo in a 6-week double-blind trial and were evaluated by changes in scores on the Hamilton Rating Scale for Depression (HAM-D) and the global improvement measure of the Clinical Global Impressions (CGI) scale. High correlations were found between the changes in HAM-D scores from baseline to endpoint and the final CGI improvement ratings. In patients with moderate depression (baseline HAM-D score of 20 or more), the differences in endpoint analysis between active treatment and placebo groups were significant. A persistent pattern of improvement was noted in 27% of those receiving fluoxetine but in none of those receiving placebo. Physician and patient evaluations as determined by the improvement measure of the CGI were closely correlated.

Fluoxetine response: endpoint vs pattern analysis

A 6-week double-blind trial of fluoxetine treatment of unipolar major depressive disorder in 49 patients was evaluated in terms of improvement in the Hamilton Depression Rating Scale (HDRS) and Clinical Global Improvement (CGI) scores. A relationship was found between change in HDRS (absolute and percentage decrease from baseline) and final CGI ratings. However, because of a few placebo-responders, endpoint analysis with both the HDRS and CGI showed no differences between active drug and placebo. Pattern analysis of persistent response did successively separate active drug from placebo (less than 0.05).

General behavior inventory: measurement of subclinical changes during depression and lithium prophylaxis

A new self-rating scale, the General Behavior Inventory (GBI), was lower in eight controls and 61 patients in remission than in 32 depressed patients. Scores of depressed patients decreased over treatment time. GBI score correlated significantly with the past occurrence of manic plus depressive symptoms per visit and past mean mood shift per visit.

Clinical and laboratory effects of discontinuation of lithium prophylaxis

Twelve patients who met Research Diagnostic Criteria for a history of bipolar affective disorder gave informed consent for open discontinuation of lithium therapy for 3 weeks. There was no significant change after lithium discontinuation in the number of depressive or manic symptoms, in mood score, in total Zung Depression score, or in any of the 20 items found in the Zung Depression scale. There were significant reductions in total severity of side effects, and improvement in the three side effects reflecting renal function: polydipsia, polyuria, and nocturia. These changes were reflected in the significant increase in urine specific gravity. Significant changes in side effects did not take place until at least 2 weeks after lithium was discontinued. Other significant relationships were found between increases in serum thyroid hormone levels and in urine specific gravity, and decreases in Vmax of platelet serotonin uptake and increases in degree of clonidine-induced hypotension.

Plasma lithium level and interepisode functioning in bipolar disorder

There were no differences in interepisode functioning or side effects between bipolar patients (N = 44) with plasma lithium levels above the median and those with levels below the median. Low levels were able to stabilize mood and individual symptoms for 40.5 months.