Lack of efficacy of fluoxetine in recurrent brief depression and suicidal attempts

Recurrent brief depression (RBD) fulfills DSM-III-R symptom criteria for major depression but the episodes are of shorter duration than the 2 weeks required by DSM-III-R. The clinical importance of the disorder has been observed in prophylactic studies of suicidal behavior. The possibility that antidepressants with selective action on the reuptake of serotonin might be effective in preventing recurrences of brief depression has been investigated. Fluoxetine in a dose of 120 mg a week, administered biweekly, had no effect on the recurrence rate, which was maintained at approximately the same rate on fluoxetine (1 every 18.7 days) as with placebo (1 every 17.6 days). In a group of patients with two or more prior episodes of suicidal behavior, there were 18 attempted suicides in the 54 patients treated with fluoxetine and the same number in the 53 patients treated with placebo. Fluoxetine neither raised nor lowered the suicide attempt rate as compared with placebo, providing no evidence to support the drug's role in either suicide provocation or prevention. Since fluoxetine is clearly effective with recurrent major depression, it would appear that recurrent brief depression has a different pharmacology.

Selective serotonin reuptake inhibitors: meta-analysis of discontinuation rates

A meta-analysis was carried out of 42 published randomized controlled studies comparing the selective serotonin reuptake inhibitors (SSRIs) with the tricyclic antidepressants (TCAs) that measured discontinuation rates for side effects and lack of efficacy by treatment group in order to compare the discontinuation rates for side effects and lack of efficacy. These discontinuation rates were pooled to produce the main outcome measure. Seven studies were placebo controlled and the discontinuation rates in these studies were also pooled in a separate analysis. Significantly fewer patients receiving SSRIs discontinued treatment because of side effects (14.9%) compared with those receiving TCAs (19%) (p < 0.01). There was also a significant difference in discontinuation rates due to side effects in the placebo- and TCA-controlled studies analysed separately, SSRIs (19%) compared with TCAs (27%) (p < 0.01). In both analyses a similar proportion of patients discontinued for lack of efficacy on SSRIs and TCAs. There is a significant and clinically important advantage for the SSRIs compared with the TCAs in the acceptability of treatment measured by the number of discontinuations due to side effects reported in published studies. The risk-benefit calculation favours the SSRIs since there were similar levels of efficacy but more discontinuations with the TCAs. The selection of an antidepressant for first-line treatment requires critical evaluation of the full risk-benefit equation.

Suicide prevention and serotonergic drugs

It is sometimes assumed that all antidepressants have a beneficial effect in reducing suicidal ideation or tendencies but there is evidence to suggest a better effect with some and that others may even provoke suicide attempts. Possible provocation of suicide attempts may be invoked to explain the high rate of attempts reported in a study with maprotiline compared with placebo and the higher rate of deaths from overdose seen with some tricyclic antidepressants. Serotonin reuptake inhibitors have been rather consistently reported to have an advantage in reducing suicidal ideation and have been shown to have a protective effect against the emergence of suicidal thoughts. In a direct test of the effect of serotonin reuptake inhibitors on suicidal behaviour there was no provocation of suicide attempts.

A double-blind, placebo-controlled study of fluoxetine in patients with DSM-III-R obsessive-compulsive disorder. The Lilly European OCD Study Group

We have studied the effect of three fixed daily doses of fluoxetine in patients with obsessive-compulsive disorder (OCD) diagnosed according to DSM-III-R. Two hundred and fourteen patients were evaluated in an 8-week double blind, placebo-controlled study. A statistically significantly greater number of fluoxetine-treated patients achieved the prospectively defined criteria for clinical response when compared to placebo treatment. There was a statistically significant overall difference in the PGI rating of symptom change (P = 0.045) and a marginally significant difference (P = 0.089) in the CGI severity rating between groups. Pairwise comparison against placebo showed a marginally statistically significantly greater improvement (P = 0.059) in Y-BOCS-Total score for patients receiving fluoxetine 60 mg daily, and a significantly higher response rate in patients receiving fluoxetine 40 mg or 60 mg daily (P < 0.05). One hundred and sixty one patients continued to a 16-week extension evaluation. There was no significant difference in the rate of reporting of any individual adverse event between placebo and fluoxetine, and the rate of discontinuation due to adverse events was low (< 6% in each study phase). This study supports the growing evidence for the safety and efficacy of fluoxetine in the treatment of OCD.

A 24-week study of 20 mg citalopram, 40 mg citalopram, and placebo in the prevention of relapse of major depression

A total of 147 patients who had responded in a placebo-controlled study to 6 weeks treatment of an episode of DSM-III-R major depression with either 20 mg or 40 mg citalopram were randomized double-blind to continue on the same dose of citalopram or to receive placebo during a 24-week study of the efficacy of citalopram in the prevention of relapse. The citalopram 20 and 40 mg groups showed a significant advantage compared with placebo both in relapses (p < 0.05) and in the survival analysis of time to relapse (p = 0.01 and p = 0.02, respectively). Both 20 and 40 mg citalopram appeared similarly safe and well tolerated with little difference in side effects from placebo. The results demonstrate that citalopram, at a dose of both 20 and 40 mg is effective and well tolerated in continuation treatment to consolidate response. The relapse rate in patients who had responded to placebo during the 6-week acute treatment study, who were continued double-blind with placebo but not included in the efficacy analysis, was similar to the rate in the formal placebo control group, suggesting that patients who respond to placebo in a short treatment course may nonetheless require long-term active treatment to prevent relapse.

Paroxetine is better than placebo in relapse prevention and the prophylaxis of recurrent depression

In an investigation of the efficacy of paroxetine in relapse prevention and prophylaxis of depression, patients who met DSM-III-R criteria for major depression with a history of two or more previous episodes in the preceding four years and who had responded to eight weeks treatment with paroxetine, were randomized double-blind to receive either paroxetine 20-30 mg or placebo for one year. One hundred and seventy-two patients entered open treatment of whom 141 completed eight weeks treatment. One hundred and thirty-five responders entered the double-blind placebo-controlled study. There was a significant advantage for paroxetine compared with placebo in the reappearance of depression (p < 0.01) and in the time to reappearance (p < 0.001) over the one-year study. A significant advantage was seen for paroxetine compared with placebo in the first four months in relapse prevention (p < 0.01) and in the time to relapse (p < 0.005), and in the later period of treatment in preventing recurrence in the time to recurrence (p < 0.05). Paroxetine was effective in preventing the reappearance of depression following an acute illness. These results confirm the benefit of long-term pharmacotherapy for treating depressive illness.

Guidelines for treating depressive illness with antidepressants: A statement from the British Association for Psychopharmacology

Depression is a common illness which affects some 3% of the population per year. At least 25% of those with marked depression do not consult their general practitioner and in half of those who do the illness is not detected. Depression is easy to recognize when four or five of the core symptoms have been present for 2 weeks which often coincides with some occupational and social impairment. The core symptoms are depressed mood, loss of interest or pleasure, loss of energy or fatigue, concentration difficulties, appetite disturbance, sleep disturbance, agitation or retardation, worthlessness or self blame and suicidal thoughts. A diagnosis of depression is made when five of these core symptoms, one of which should be depressed mood or loss of interest or pleasure, have been present for 2 weeks. Four core symptoms are probably sufficient. Response to antidepressants is good in those with more than mild symptoms. When there are only few or very mild depressive symptoms evidence of response to antidepressants is more uncertain. Antidepressants are effective, they are not addictive and do not lose efficacy with prolonged use. The newer antidepressants have fewer side effects than the older tricyclics, they are better tolerated and lead to less withdrawals from treatment. They are less cardiotoxic and are safer in overdose. Antidepressants should be used at full therapeutic doses. Treatment failure is often due to too low a dose being used in general practice. It may be difficult to reach the right dose with the older tricyclics because of side effects. To consolidate response, treatment should be continued for at least 4 months after the patient is apparently well. Stopping the treatment before this is ill-advised as the partially treated depression frequently returns. Most depression is recurrent. Long-term antidepressant treatment is effective in reducing the risk of new episodes of depression and should be continued to keep the patient well.

Features of recurrent brief depression

Recurrent brief depression, characterised by frequently occurring brief depressive episodes, lasting less than two weeks, is now recognised as a common and disabling illness with a chronic relapsing course and a significant suicide risk. The episodes have a mean duration of 3 days, but otherwise fulfill the symptomatic criteria for DSM III-R major depression. Some two thirds of episodes satisfy severity criteria for at least moderate depression and about a third for severe depression. They recur erratically with a mean period of 18 days between the start of one episode and the next. Because of the frequency of the episodes patients may report longer continuous periods of depression than was the case and may be mistakenly perceived as dysthymia as major depression. It is important to identify these patients as treatment response appears to differ. The episodes are too short to be able to assume efficacy with conventional antidepressants; it is necessary to adopt a prophylactic strategy for treatment aiming to reduce the severity, the frequency, or the duration of episodes.

Inadequate treatment response to des-enkephalin-gamma-endorphin compared with thioridazine and placebo in schizophrenia

The possibility of an involvement of peptidergic systems in schizophrenia has been under investigation for a number of years. Studies of the efficacy of des-tyr-gamma-endorphin were equivocal; more recent studies with des-enkephalin-gamma-endorphin have reported some activity but the peptide has only been investigated as an adjunct to neuroleptic medication, apart from one very small active reference comparator study. In the multicentre study reported here, 96 patients suffering from schizophrenia (DSM-III with a current exacerbation if chronic) were allocated randomly to double-blind treatment with either des-enkephalin-gamma-endorphin (DE-gamma-E) (Org 5878) 10 mg given as a once daily intramuscular injection for 4 weeks, thioridazine 400 mg orally in 2 divided doses or placebo using a double-dummy technique to preserve blindness. There was a significant advantage for thioridazine compared with placebo registered on all measures at weeks 3 and 4. There was no difference between DE-gamma-E and placebo. There was a significant difference between thioridazine and DE-gamma-E at weeks 3 and 4 registered on the MSS and at week 3 registered on the BPRS. The lack of efficacy of DE-gamma-E suggests that the theories that the endorphins have an important role in schizophrenia have to be revised. The need for well designed placebo controlled studies for assessing efficacy in schizophrenia is emphasized.

Fluvoxamine in the treatment of obsessive compulsive disorder

Obsessive compulsive disorder is a chronic, often severe condition that is associated with considerable long term morbidity and suffering. Potent serotonin reuptake inhibitors are now regarded as first line treatments and their efficacy has been established in a series of placebo-controlled studies. The first of these compounds to become available, clomipramine, has undesirable effects on a number of other receptor systems and is associated with marked anticholinergic side effects. Of the selective serotonin reuptake inhibitors fluvoxamine is the most widely studied, with three small positive placebo-controlled and two recent large multicentre studies. These two studies show that fluvoxamine is associated with significant improvement on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), the National Institute of Mental Health Obsessive Compulsive Scale (NIMH-OC) and the Global Improvement item of the Clinical Global Impression (CGImp) Scale, compared with placebo.

The advantages of paroxetine in different subgroups of depression

Paroxetine is a selective serotonin reuptake inhibitor that is now licensed in various countries in Europe. It has comparable efficacy with the reference tricyclic antidepressants and is well tolerated with few adverse effects which are usually mild, transient and do not appear to compromise treatment. Paroxetine has a number of advantages as an antidepressant; of particular interest is its ability to improve sleep early in treatment without daytime sedation or interference with psychomotor function. Paroxetine appears effective compared with placebo in different subgroups of depression: it is effective in both endogenous and reactive depression, as well as being effective in moderate and severe depression. Paroxetine appears particularly effective in treating the anxiety associated with depression and has been shown to have greater efficacy than imipramine. There is some evidence that the onset of antidepressant action occurs slightly earlier with paroxetine than with imipramine. As well as being effective in the acute episode, placebo-controlled, long-term data are available indicating paroxetine to be of value in the prevention of depressive relapse.

Pharmacotherapy in the prevention of suicidal behavior

Prevention or reduction of suicide remains a serious challenge for the medical community. Psychotherapeutic and psychosocial interventions have not been shown to reduce the incidence of suicide attempts and analytic psychotherapy has been shown to increase suicidal behavior. The efficacy of pharmacotherapy in reducing suicide attempts in patients with a history of repeated suicidal behavior has been shown with low doses of the neuroleptic agent flupenthixol compared with placebo. Supporting findings have been reported with trifluoperazine. There is evidence to suggest that some antidepressants may not be neutral in their effect on suicidal behavior. Maprotiline, for example, was associated with an increase in suicide attempts compared with placebo in a large long-term treatment study despite its significant efficacy in preventing relapse of depression. Differential lethality indices taken from large community studies support the notion that noradrenergic drugs such as maprotiline, desipramine, and nortriptyline are associated with a higher than expected incidence of death from overdose, and the suicide-provoking potential may relate to some noradrenergic property. The studies of serotonergic antidepressants do not suggest that they are suicide-provoking agents; rather they appear to be neutral or protective. Prospective prophylactic studies are needed to test the ability of potential treatments for the reduction of suicidal behavior.