A double-blind comparison of citalopram (Lu 10-171) and amitriptyline in depressed patients

Synthesis and Antimicrobial Screening of Novel 4-Substituted Phenyl-5-[1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-yl]-2H-1,2,4-triazole-3-thiones

The paper describes a convenient method for the preparation of 4-substituted phenyl-5-[1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-yl]-2H-1,2,4-triazole-3-thiones. The structures of the synthesized compounds are established by the results of LCMS, ¹H NMR, ¹³C NMR, and IR and elemental analyses. The mercaptotriazoles are indicated to be in thione form by ¹H NMR spectra. All the synthesized compounds have been screened for antibacterial and antifungal activities. Compounds 12d and 12h exhibit encouraging results, while the remaining compounds show moderate activities. On the basis of spectral studies, formation of 2-amino-1,3,4-thiadiazoles from the isobenzofuran acyl thiosemicarbazides 11(a–h) is ruled out.

Information for physicians and pharmacists about drugs that might cause dry mouth: a study of monographs and published literature

BACKGROUND

Over three-quarters of the older population take medications that can potentially cause dry mouth. Physicians or pharmacists rarely inform patients about this adverse effect and its potentially severe damage to the teeth, mouth and general health.

OBJECTIVES

The objectives of this study were to (1) identify warnings in the literature about dry mouth associated with the most frequently prescribed pharmaceutical products in Canada; and (2) consider how this information might be obtained by physicians, pharmacists and patients.

METHODS

Monographs on the 72 most frequently prescribed medications during 2010 were retrieved from the Compendium of Pharmaceuticals and Specialties (CPS, a standard drug information reference for physicians and pharmacists), the National Library of Medicine's 'DailyMed' database, directly from the manufacturers, and from a systematic search of biomedical journals.

RESULTS

The CPS provided monographs for 43% of the medications, and requests to manufacturers produced the remaining monographs. Mentions of dry mouth were identified in 61% of the products (43% amongst CPS monographs; an additional 43% amongst manufacturers' monographs; 7% in the DailyMed database and 7% from biomedical journals); five medications had contradictory reports in different monographs.

CONCLUSION

Nearly two-thirds (61%) of the most commonly prescribed medications can cause dry mouth, yet warnings about this adverse effect and its potentially serious consequences are not readily available to physicians, pharmacists, dentists or patients.

Citalopram versus other anti-depressive agents for depression

BACKGROUND

Recent US and UK clinical practice guidelines recommend that second-generation antidepressants should be considered amongst the best first-line options when drug therapy is indicated for a depressive episode. Systematic reviews have already highlighted some differences in efficacy between second-generation antidepressants. Citalopram, one of the first selective serotonin reuptake inhibitors (SSRI) introduced in the market, is one of these antidepressant drugs that clinicians use for routine depression care.

OBJECTIVES

To assess the evidence for the efficacy, acceptability and tolerability of citalopram in comparison with tricyclics, heterocyclics, other SSRIs and other conventional and non-conventional antidepressants in the acute-phase treatment of major depression.

SEARCH METHODS

We searched The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to February 2012. No language restriction was applied. We contacted pharmaceutical companies and experts in this field for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating patients with major depression to citalopram versus any other antidepressants.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy (the number of patients who responded or remitted), patient acceptability (the number of patients who failed to complete the study) and tolerability (side-effects).

MAIN RESULTS

Thirty-seven trials compared citalopram with other antidepressants (such as tricyclics, heterocyclics, SSRIs and other antidepressants, either conventional ones, such as mirtazapine, venlafaxine and reboxetine, or non-conventional, like hypericum). Citalopram was shown to be significantly less effective than escitalopram in achieving acute response (odds ratio (OR) 1.47, 95% confidence interval (CI) 1.08 to 2.02), but more effective than paroxetine (OR 0.65, 95% CI 0.44 to 0.96) and reboxetine (OR 0.63, 95% CI 0.43 to 0.91). Significantly fewer patients allocated to citalopram withdrew from trials due to adverse events compared with patients allocated to tricyclics (OR 0.54, 95% CI 0.38 to 0.78) and fewer patients allocated to citalopram reported at least one side effect than reboxetine or venlafaxine (OR 0.64, 95% CI 0.42 to 0.97 and OR 0.46, 95% CI 0.24 to 0.88, respectively).

AUTHORS' CONCLUSIONS

Some statistically significant differences between citalopram and other antidepressants for the acute phase treatment of major depression were found in terms of efficacy, tolerability and acceptability. Citalopram was more efficacious than paroxetine and reboxetine and more acceptable than tricyclics, reboxetine and venlafaxine, however, it seemed to be less efficacious than escitalopram. As with most systematic reviews in psychopharmacology, the potential for overestimation of treatment effect due to sponsorship bias and publication bias should be borne in mind when interpreting review findings. Economic analyses were not reported in the included studies, however, cost effectiveness information is needed in the field of antidepressant trials.

Added-metal-free catalytic nucleophilic addition of Grignard reagents to ketones

On the basis of the investigation of the combinational effect of quaternary ammonium salts and organic bases, an added-metal-free catalytic system for nucleophilic addition reactions of a variety of Grignard reagents to diverse ketones in THF solvent has been developed to produce tertiary alcohols in good to excellent yields. By using tetrabutylammonium chloride (NBu(4)Cl) as a catalyst and diglyme (DGDE) as an additive, this system strongly enhances the efficiency of addition at the expense of enolization and reduction. NBu(4)Cl should help to shift the Schlenk equilibrium of Grignard reagents to the side of dimeric Grignard reagents to favor the additions of Grignard reagents to ketones via a favored six-membered transition state to form the desired tertiary alcohols, and DGDE should increase the nucleophilic reactivities of Grignard reagents by coordination. This catalytic system has been applied in the efficient synthesis of Citalopram, an effective U.S. FDA-approved antidepressant, and a recyclable version of this catalytic synthesis has also been devised.

WITHDRAWN: Treatment discontinuation with selective serotonin reuptake inhibitors (SSRIs) versus tricyclic antidepressants (TCAs)

BACKGROUND

Selective serotonin reuptake inhibitors are thought to have better discontinuation rates (i.e. less people dropping out) than tricyclic and heterocyclic antidepressant drugs. It is important to quantify the drop-out rates of different antidepressant drugs in order to have a better understanding of the relative tolerability of these drugs.

OBJECTIVES

To assess the comparative tolerability of selective serotonin reuptake inhibitors and tricyclic/heterocyclic antidepressant drugs.

SEARCH STRATEGY

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (1997 to 1999), MEDLINE (1966 to 1999), EMBASE (1974 to 1999) We also searched specialist journals, the reference lists of relevant papers and previous systematic reviews, conference abstracts and government documents. Representatives of the pharmaceutical industry were contacted.

SELECTION CRITERIA

Parallel group randomised controlled trials comparing selective serotonin reuptake inhibitors with tricyclic or heterocyclic antidepressants in people with depression.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and a third reviewer checked any cases of disagreement.

MAIN RESULTS

We included 136 trials. The selective serotonin reuptake inhibitors showed less participants dropping out compared to the tricyclic/heterocyclic group (odds ratio 1.21, 95% confidence interval 1.12 to 1.30). A statistically significant difference was found in total drop-outs between the selective serotonin reuptake inhibitors and the old tricyclics as well as the newer tricyclics. When the selective serotonin reuptake inhibitors were compared to the heterocyclic antidepressants, there was a non significant difference favouring the selective serotonin reuptake inhibitors. The poor tolerability profile of the old tricyclics was explained by differences in drop-outs for side-effects, but not for inefficacy.

AUTHORS' CONCLUSIONS

Whilst selective serotonin reuptake inhibitors do appear to show an advantage over tricyclic drugs in terms of total drop-outs, this advantage is relatively modest. This has implications for pharmaco-economic models, some of which may have overestimated the difference of drop-out rates between selective serotonin reuptake inhibitors and tricyclic antidepressants. These results are based on short-term randomised controlled trials, and may not generalise into clinical practice.

Amitriptyline for depression

BACKGROUND

For many years amitriptyline has been considered one of the reference compounds for the pharmacological treatment of depression. However, new tricyclic drugs, heterocyclic compounds and selective serotonin reuptake inhibitors have been introduced on the market with the claim of a more favourable tolerability/efficacy profile.

OBJECTIVES

The aim of the present systematic review was to investigate the tolerability and efficacy of amitriptyline in comparison with the other tricyclic/heterocyclic antidepressants and with the selective serotonin reuptake inhibitors.

SEARCH STRATEGY

The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR-Studies) was searched on 28-11-2005. Reference lists of all included studies were checked.

SELECTION CRITERIA

Only randomised controlled trials were included. Study participants were of either sex and any age with a primary diagnosis of depression. Included trials compared amitriptyline with another tricyclic/heterocyclic antidepressant or with one of the selective serotonin reuptake inhibitors.

DATA COLLECTION AND ANALYSIS

Data were extracted using a standardised form. The number of patients undergoing the randomisation procedure, the number of patients who completed the study and the number of improved patients were extracted. In addition, group mean scores at the end of the trial on Hamilton Depression Scale or any other depression scale were extracted. In the tolerability analysis, the number of patients failing to complete the study and the number of patients complaining of side-effects were extracted.

MAIN RESULTS

A total number of 194 studies were included in the review. The estimate of the overall odds ratio (OR) for responders showed that more subjects responded to amitriptyline in comparison with the control antidepressant group (OR 1.12 to 95% confidence interval (CI) 1.02 to 1.23, number needed to treat to benefit (NNTB) = 50). The estimate of the efficacy of amitriptyline and control agents on a continuous outcome revealed an effect size which also significantly favoured amitriptyline (Standardised Mean Difference (SMD) 0.13, 95% CI 0.04 to 0.23). Whilst these differences are statistically significant, their clinical significance is less clear. When the efficacy analysis was stratified by drug class, no difference in outcome emerged between amitriptyline and either tricyclic or selective serotonin reuptake inhibitor comparators. The dropout rate in patients taking amitriptyline and control agents was similar; however, the estimate of the proportion of patients who experienced side-effects significantly favoured control agents in comparison with amitriptyline (OR 0.66, 95% CI 0.59 to 0.74). When the tolerability analysis was stratified by drug class, the dropout rate in patients taking amitriptyline and the selective serotonin reuptake inhibitors significantly favoured the latter (OR 0.84, 95% CI 0.75 to 0.95, number needed to treat to harm (NNTH) = 40). When the responder analysis was stratified by study setting amitriptyline was more effective than control antidepressants in inpatients (OR 1.22, 95% CI 1.04 to 1.42, NNTB = 24), but not in outpatients (OR 1.01, 95%CI 0.88 to 1.17, NNTB = 200).

AUTHORS' CONCLUSIONS

This present systematic review indicates that amitriptyline is at least as efficacious as other tricyclics or newer compounds. However, the burden of side-effects in patients receiving it was greater. In comparison with selective serotonin reuptake inhibitors amitriptyline was less well tolerated, and although counterbalanced by a higher proportion of responders, the difference was not statistically significant.

WITHDRAWN: Selective serotonin reuptake inhibitors (SSRIs) versus other antidepressants for depression

BACKGROUND

The relatively new class of antidepressant, the selective serotonin reputake inhibitors (SSRIs), may be better tolerated than the older tricyclic antidepressants. This review compares the efficacy of SSRIs with other antidepressants.

OBJECTIVES

To examine the relative efficacy of selective serotonin reuptake inhibitors (SSRIs) compared to other antidepressants.

SEARCH STRATEGY

The search strategy included a search of (a) Electronic bibliographic databases (MEDLINE, EMBASE); (b) reference lists of related reviews (c) reference lists of all located studies (d) contact with the manufacturer and (e) the Cochrane Group register of controlled trials

SELECTION CRITERIA

Randomised controlled trials comparing selective serotonin reuptake inhibitors with other kinds of antidepressants in the treatment of patients with depressive disorders. The outcome measures assessed included measures of the severity of depression.

DATA COLLECTION AND ANALYSIS

Data were collected from each study the main outcome measurefrom each study. These included: mean Hamilton depression rating scale, mean Montgomery & Asberg depression rating scale, Clinical Global Impression rating scale. An analysis of standardised mean difference of these scales was performed using Review Manager 3.1 software. The presence of heterogeneity of treatment effect was assessed

MAIN RESULTS

Ninety-eight trials contributed data to the analysis of the relative efficacy of SSRIs and related drugs with comparator antidepressants (Figure 3 & Appendix 3). Analysis of efficacy was based upon 5044 patients treated with an SSRI or related drug, and 4510 treated with an alternative antidepressant. The standardised effect size for SSRIs and related drugs together versus alternative antidepressants using a fixed effects model was 0.035 (95% CI -0.006 to 0.076; Q = 149.25, df = 97, p < 0.001).

AUTHORS' CONCLUSIONS

There are no clinically significant differences in effectiveness between selective serotonin reuptake inhibitors and tricyclic antidepressants. Treatment decisions need to be based on considerations of relative patient acceptability, toxicity and cost.

Efficacy and safety of citalopram versus amitriptyline in the treatment of major depression

BACKGROUND

Double-blind clinical trials comparing citalopram with amitriptyline or other tricyclic antidepressants are lacking in India.

AIM

To evaluate the efficacy and safety of the newer antidepressant citalopram in the treatment of major depression.

METHODS

The clinical acceptability and safety profile of citalopram was assessed and compared with that of amitriptyline in 40 patients in an outpatient set-up. Patients aged 18 to 65 years who fulfilled the diagnostic criteria for a single or recurrent major depressive disorder (as defined by DSM-IV) for a minimum of 2 weeks were enrolled. Patient assessment was done at screening, baseline, end of week 1, week 2, week 3, week 4, week 5 and week 6 for efficacy and safety parameters such as Hamilton Depression Rating Scale (HDRS), Clinical Global Impression (CGI) Scale, adverse event follow up, blood pressure and pulse. Three-level statistical analysis including ANOVA was performed on all efficacy measures.

RESULTS

On the HDRS the percentage reduction in the mean score for the citalopram group (Group 1) was 72.12%, while that for the amitriptyline group (Group 2) was 67.93%. On the CGI-Improvement Scale, the percentage reduction at the end of the study for the citalopram group was 56.79% while in the amitriptyline group it was 44.70%. Twenty per cent of patients in Group 1 reported adverse events compared to 75% in Group 2.

CONCLUSIONS

Citalopram is effective in the treatment of major depression at the dosages range of 20-60 mg/day and its efficacy is equivalent to that of standard tricyclic antidepressants such as amitriptyline, with a substantially better tolerability profile.

Clinical trials of potential antidepressants: to what extent are the elderly represented: a review

BACKGROUND

There is widespread use of antidepressants in the elderly population. The principle of treatment of depression, however, is derived mostly from studies employing young adults and healthy elderly. This article reviews the literature on the extent to which the elderly are represented in clinical trials of potential antidepressants.

METHOD

Medline search of relevant articles of clinical trials of potential antidepressants.

RESULTS

The maximum age of inclusion for most clinical trials was 65 years. The highest age reported for depressed subjects was 90 years. There was no clear consensus on who were considered to be elderly; clinical trials conducted on the elderly included subjects who were 50, 55, or 60 years and over. Pharmacological studies on healthy subjects were most often done on young adults, age range 18 to 65 years. The period of study was relatively shorter for clinical trials done on elderly subjects. There was however, no difference in the exclusion or inclusion criteria between studies done in young and elderly subjects.

CONCLUSIONS

Elderly subjects aged 75 years and over were clearly underrepresented in the clinical trials of potential antidepressants. For drugs that are used by the elderly, in its pivotal studies for registration, the inclusion of at least 25% of subjects aged 75 years and over is recommended.

Amitriptyline versus other types of pharmacotherapy for depression

BACKGROUND

For many years amitriptyline has been considered one of the reference compounds for the pharmacological treatment of depression. However, new tricyclic drugs, heterocyclic compounds and the selective serotonin reuptake inhibitors have been introduced on the market with the claim of a more favourable tolerability/efficacy profile.

OBJECTIVES

The aim of the present systematic review was to investigate the tolerability and efficacy of amitriptyline in comparison with the other tricyclic/heterocyclic antidepressants and with the selective serotonin reuptake inhibitors.

SEARCH STRATEGY

The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (2002-3) and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched. Key journals and conference abstracts were handsearched. Pharmaceutical companies were contacted for information on unpublished materials.

SELECTION CRITERIA

Only randomised controlled trials were included. Study participants were of either sex and any age with a primary diagnosis of depression. Included trials compared amitriptyline with another tricyclic/heterocyclic antidepressant or with one of the selective serotonin reuptake inhibitors.

DATA COLLECTION AND ANALYSIS

Data were extracted using a standardised form. The number of patients undergoing the randomisation procedure, the number of patients who completed the study and the number of improved patients were extracted. In addition, group mean scores at the end of the trial on Hamilton Depression Scale or any other depression scale were extracted. In the tolerability analysis, the number of patients failing to complete the study and the number of patients complaining of side-effects was extracted.

MAIN RESULTS

The estimate of the overall odds ratio for responders showed that more subjects responded to amitriptyline in comparison with the control antidepressant group (odds ratio 1.12, 95% confidence interval 1.01, 1.23, number needed to treat 50). The estimate of the efficacy of amitriptyline and control agents on a continuous outcome revealed an effect size which also significantly favoured amitriptyline (Standardised Mean Difference 0.13, 95% confidence interval 0.04, 0.23). Whilst these differences are statistically significant, their clinical significance is less clear. When the efficacy analysis was stratified by drug class, no difference in outcome emerged between amitriptyline and either tricyclic or selective serotonin reuptake inhibitor comparators. The dropout rate in patients taking amitriptyline and control agents was similar; however, the estimate of the proportion of patients who experienced side-effects significantly favoured control agents in comparison with amitriptyline (odds ratio 0.63, 95% confidence interval 0.56, 0.71). When the tolerability analysis was stratified by drug class, the dropout rate in patients taking amitriptyline and the selective serotonin reuptake inhibitors significantly favoured the latter (odds ratio 0.84, 95% confidence interval 0.75,0.95, number needed to harm 40). When the responder analysis was stratified by study setting amitriptyline was more effective than control ADs in inpatients (odds ratio 1.22, 95% confidence interval 1.04, 1.42, number needed to treat 24), but not in outpatients (odds ratio 1.01, 95% confidence interval 0.88, 1.17, number needed to treat = 200).

REVIEWER'S CONCLUSIONS

This present systematic review indicates that amitriptyline is at least as efficacious as other tricyclics or newer compounds. However, the burden of side-effects in patients receiving it was greater. In comparison with the selective serotonin reuptake inhibitors amitriptyline was less well tolerated, and although counterbalanced by a higher proportion of responders, the difference was not statistically significant.

Citalopram: a comprehensive review

Citalopram is a selective serotonin re-uptake inhibitor that has demonstrated antidepressant efficacy in numerous controlled clinical trials. Additional studies have shown that the drug benefits patients with other illnesses that are related in some way to serotonergic dysfunction, including anxiety, panic disorder, obsessive-compulsive disorder, premenstrual dysphoria, alcohol dependence and the behavioural disturbances of dementia. This paper reviews the full spectrum of citalopram's clinical efficacy, as well as its safety and tolerability, in a range of patients.

Acute and chronic effects of citalopram on postsynaptic 5-hydroxytryptamine(1A) receptor-mediated feedback: a microdialysis study in the amygdala

Microdialysis was used to assess the involvement of postsynaptic 5-hydroxytryptamine(1A) (5-HT(1A)) receptors in the regulation of extracellular 5-HT in the amygdala. Local infusion of the 5-HT(1A) receptor agonist flesinoxan (0.3, 1, 3 microM) for 30 min into the amygdala maximally decreased 5-HT to 50% of basal level. Systemic administration of citalopram (10 micromol/kg) increased 5-HT to 175% of basal level. Local infusion of 1 microM of the 5-HT(1A) receptor antagonist WAY 100.635 into the amygdala augmented the effect of citalopram to more than 500% of basal 5-HT level. 5-HT(1A) receptor responsiveness after chronic citalopram treatment was determined in two ways. First, by local infusion of 1 microM flesinoxan for 30 min into the amygdala, which showed a significant 63% reduction in response (area under the concentration-time curve; AUC) for the citalopram group compared to the saline group. Second, by systemic administration of citalopram (10 micromol/kg), which increased 5-HT to 350% of basal level. The effect was larger than in untreated animals, but more important, local infusion of 1 microM WAY 100.635 into the amygdala now failed to augment the effect of citalopram. Both the flesinoxan and WAY 100.635 data suggest an involvement of postsynaptic 5-HT(1A) receptor-mediated feedback in the amygdala, which diminishes following chronic citalopram treatment.

Amitriptyline v. the rest: still the leading antidepressant after 40 years of randomised controlled trials

BACKGROUND

Tricyclic antidepressants have similar efficacy and slightly lower tolerability than selective serotonin reuptake inhibitors (SSRIs). However, there are no systematic reviews assessing amitriptyline, the reference tricyclic drug, v. other tricyclics and SSRIs directly.

AIMS

To review the tolerability and efficacy of amitriptyline in the management of depression.

METHOD

A systematic review of randomised controlled trials (RCTs) comparing amitriptyline with other tricyclics/heterocyclics or with an SSRI.

RESULTS

We reviewed 186 RCTs. The overall estimate of the efficacy of amitriptyline revealed a standardised mean difference of 0.147 (95% CI 0.05-0.243), significantly favouring amitriptyline. The overall OR for dropping out was 0.99 (95% CI 0.91-1.08) and that for side-effects was 0.62 (95% CI 0.54-0.70), favouring the control drugs. With drop-outs included as treatment failures, the estimate of the effectiveness of amitriptyline v. tricyclics/heterocyclics and SSRIs showed a 2.5% difference in the proportion of responders in favour of amitriptyline (number needed to treat 40, CI 21-694; OR 1.12 (95% CI 1.01-1.24)).

CONCLUSIONS

Amitriptyline is less well tolerated than tricyclics/heterocyclics and SSRIs, but slightly more patients treated on it recover than on alternative antidepressants.

Citalopram in the treatment of depression

OBJECTIVE

To review the efficacy and safety of citalopram in the treatment of depression.

DATA SOURCES

MEDLINE search (1966-April 2000), Current Contents search, additional references listed in articles, and unpublished data obtained from the manufacturer were used to identify data from scientific literature. Studies evaluating citalopram (i.e., abstracts, clinical trials, data on file with the manufacturer) were considered for inclusion.

STUDY SELECTION

English-language literature was reviewed to evaluate the pharmacology, pharmacokinetics, therapeutic use, and adverse effects of citalopram.

DATA EXTRACTION

Controlled animal and human clinical studies published in the English-language literature were reviewed and evaluated. Clinical trials selected for inclusion were limited to those in human subjects and included data from animals if human data were not available.

DATA SYNTHESIS

Citalopram is an antidepressant belonging to the class of selective serotonin-reuptake inhibitors (SSRIs) available for the treatment of depression. Citalopram offers therapeutic efficacy similar to that of the other SSRIs and a more favorable adverse effect profile than that of the tricyclic antidepressants (TCAs). Citalopram does not cause anticholinergic or cardiovascular adverse effects associated with the TCAs. Citalopram is the most selective SSRI and, unlike other SSRIs, seems to be relatively free of interaction mediated by the cytochrome P450 system. Citalopram is also the least expensive antidepressant available to date. This review of citalopram includes data from clinical trials comparing safety, tolerability, efficacy, and pharmacoeconomics with TCAs and SSRIs.

CONCLUSIONS

Clinical trials demonstrate that citalopram's therapeutic efficacy is significantly greater than that of placebo and is comparable with that of other antidepressants. Citalopram has a favorable adverse effect profile, and thus may be useful in treating depressed patients who cannot tolerate anticholinergic or cardiovascular adverse effects associated with TCAs. It may also be useful in patients with comorbid illnesses requiring concomitant medicines.

Selective serotonin reuptake inhibitors versus tricyclic antidepressants: a meta-analysis of efficacy and tolerability

BACKGROUND

A meta-analysis of the efficacy and tolerability of selective serotonin reuptake inhibitors (SSRIs) against tricyclic antidepressants (TCAs) in depressed patients was carried out.

METHODS

Efficacy data from 102 randomised controlled trials (10706 patients) were pooled to provide a summary variance-weighted effect size. Tolerability data from 95 studies (10553 patients) were combined to give variance-weighted relative risk of drop out for all reasons and for adverse effects from each study. The effect of age, treatment setting, severity and TCA dose were examined as well as the performance of individual SSRIs and TCAs where there were sufficient studies.

RESULTS

There is no overall difference in efficacy between SSRIs and TCAs (effect size -0.03, 95% confidence interval -0.09 to 0.03). TCAs do appear more effective in in-patients (-0.23, -0.40 to -0.05) and amitriptyline is more effective than SSRI comparators (-0.14, -0.25 to -0.03) but publication bias cannot be excluded. The SSRIs are better tolerated, with significantly lower rates of treatment discontinuations overall (relative risk 0.88, 0.83 to 0.93; number needed to treat 26) and due to side effects (0.73, 0.67 to 0.80; number needed to treat 33). Individual SSRIs show a similar advantage except for fluvoxamine which does not differ from the TCAs. Individual TCAs show a similar disadvantage in tolerability compared to SSRIs except for dothiepin against which SSRI treatment results in more side-effect related drop outs (2.64, 1.50 to 4.63; number needed to harm 12).

LIMITATIONS

The evidence is from short-term studies and subgroup analyses may result in chance results.

CONCLUSIONS

Overall efficacy between the two classes is comparable but SSRIs are not proven to be as effective as TCAs in in-patients and against amitriptyline. SSRIs have a modest advantage in terms of tolerability against most TCAs.

SSRIs versus other antidepressants for depressive disorder

OBJECTIVES

To examine the relative efficacy of selective serotonin reuptake inhibitors (SSRIs) compared to other antidepressants.

SEARCH STRATEGY

The search strategy included a search of (a) Electronic bibliographic databases (MEDLINE, EMBASE); (b) reference lists of related reviews (c) reference lists of all located studies (d) contact with the manufacturer and (e) the Cochrane Group register of controlled trials

SELECTION CRITERIA

Randomised controlled trials comparing selective serotonin reuptake inhibitors with other kinds of antidepressants in the treatment of patients with depressive disorders. The outcome measures assessed included measures of the severity of depression.

DATA COLLECTION AND ANALYSIS

Data were collected from each study the main outcome measurefrom each study. These included: mean Hamilton depression rating scale, mean Montgomery & Asberg depression rating scale, Clinical Global Impression rating scale. An analysis of standardised mean difference of these scales was performed using Review Manager 3. 1 software. The presence of heterogeneity of treatment effect was assessed

MAIN RESULTS

Ninety-eight trials contributed data to the analysis of the relative efficacy of SSRIs and related drugs with comparator antidepressants (Figure 3 & Appendix 3). Analysis of efficacy was based upon 5044 patients treated with an SSRI or related drug, and 4510 treated with an alternative antidepressant. The standardised effect size for SSRIs and related drugs together versus alternative antidepressants using a fixed effects model was 0. 035 (95% CI -0.006 to 0.076; Q = 149.25, df = 97, p < 0.001).

REVIEWER'S CONCLUSIONS

There are no clinically significant differences in effectiveness between selective serotonin reuptake inhibitors and tricyclic antidepressants. Treatment decisions need to be based on considerations of relative patient acceptability, toxicity and cost.

Selective serotonin reuptake inhibitors versus tricyclic and heterocyclic antidepressants: comparison of drug adherence

BACKGROUND

Selective serotonin reuptake inhibitors are thought to have better discontinuation rates (i.e. less people dropping out) than tricyclic and heterocyclic antidepressant drugs. It is important to quantify the drop-out rates of different antidepressant drugs in order to have a better understanding of the relative tolerability of these drugs.

OBJECTIVES

To assess the comparative tolerability of selective serotonin reuptake inhibitors and tricyclic/heterocyclic antidepressant drugs.

SEARCH STRATEGY

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (1997 to 1999), MEDLINE (1966 to 1999), EMBASE (1974 to 1999) We also searched specialist journals, the reference lists of relevant papers and previous systematic reviews, conference abstracts and government documents. Representatives of the pharmaceutical industry were contacted.

SELECTION CRITERIA

Parallel group randomised controlled trials comparing selective serotonin reuptake inhibitors with tricyclic or heterocyclic antidepressants in people with depression.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data and a third reviewer checked any cases of disagreement.

MAIN RESULTS

We included 136 trials. The selective serotonin reuptake inhibitors showed less participants dropping out compared to the tricyclic/heterocyclic group (odds ratio 1.21, 95% confidence interval 1.12 to 1.30). A statistically significant difference was found in total drop-outs between the selective serotonin reuptake inhibitors and the old tricyclics as well as the newer tricyclics. When the selective serotonin reuptake inhibitors were compared to the heterocyclic antidepressants, there was a non significant difference favouring the selective serotonin reuptake inhibitors. The poor tolerability profile of the old tricyclics was explained by differences in drop-outs for side-effects, but not for inefficacy.

REVIEWER'S CONCLUSIONS

Whilst selective serotonin reuptake inhibitors do appear to show an advantage over tricyclic drugs in terms of total drop-outs, this advantage is relatively modest. This has implications for pharmaco-economic models, some of which may have overestimated the difference of drop-out rates between selective serotonin reuptake inhibitors and tricyclic antdepressants. These results are based on short-term randomised controlled trials, and may not generalise into clinical practice.

Citalopram in the treatment of depression and other potential uses in psychiatry

During the past decade, treatment options for depression have increased with the introduction of new agents. Older agents, such as tricyclic antidepressants and monoamine oxidase inhibitors, increase noradrenergic and serotonergic neurotransmission. Attempts to separate antidepressant effects from adverse effects led to the development of selective serotonin reuptake inhibitors (SSRIs). Citalopram is the newest SSRI to be marketed in the United States. Of all SSRIs on the market, it is the most selective for serotonin reuptake pump. Its efficacy in treating depression was evident in both placebo-controlled and comparator trials. In addition, citalopram was studied in the treatment of other psychiatric disorders. The agent has less inhibition of cytochrome P450 enzymes than other SSRIs, possibly giving it a lower potential for drug interactions.

Treatment discontinuation with selective serotonin reuptake inhibitors compared with tricyclic antidepressants: a meta-analysis

OBJECTIVE

To assess treatment discontinuation rates with selective serotonin reuptake inhibitors compared with tricyclic antidepressants.

DESIGN

Meta-analysis of 62 randomised controlled trials.

SUBJECTS

6029 patients with major unipolar depression.

MAIN OUTCOME MEASURES

Pooled risk ratios for drop out rates with respect to all cases of discontinuation and those due to side effects and treatment failure.

RESULTS

The total discontinuation rate was 10% lower with selective serotonin reuptake inhibitors than with tricyclic antidepressants (risk ratio 0.90; 95% confidence interval 0.84 to 0.97) and the drop out rate due to side effects was 25% lower (risk ratio 0.75; 0.66 to 0.84). There was no significant difference between drug classes in the drop out rates for treatment failure. The risk ratios for drop out did not differ significantly between individual selective serotonin reuptake inhibitors.

CONCLUSIONS

Selective serotonin reuptake inhibitors are better tolerated than tricyclic antidepressants as measured by total numbers of drop outs. The definite advantage to selective serotonin reuptake inhibitors is explained by fewer drop outs due to side effects. The overall difference, however, is comparatively small and may not be clinically relevant. Analyses of cost effectiveness should not overestimate the advantage to selective serotonin reuptake inhibitors.

Citalopram, a serotonin reuptake inhibitor, and brain ischemia in SHR

The effects of citalopram, a serotonin (5-HT) reuptake inhibitor, on cerebral blood flow (CBF) and concentration of 5-HT and its metabolite were investigated in spontaneously hypertensives rats (SHR) subjected to forebrain ischemia. Cerebral ischemia was induced by bilateral carotid artery occlusion. The concentration of the 5-HT metabolite, 5-hydroxyindoleacetic acid (5-HIAA), increased during cerebral ischemia in most brain regions examined, while that of 5-HT increased only in the frontal cortex and the striatum. Citalopram restored the 5-HIAA concentrations to the preischemic normal levels. Citalopram had no effect on the cortical CBF, before and during ischemia. These results suggest that citalopram attenuates ischemia-induced hypermetabolism of 5-HT in the brain. The effects of citalopram are independent of hemodynamic factors including cerebral blood flow, and are likely to be mediated by a direct inhibition of the neuronal 5-HT reuptake system.

The anticonvulsant effect of citalopram on El mice, and the levels of tryptophan and tyrosine and their metabolites in the brain

Serotonin(5-HT) plays an important role in the seizures of El mice since the seizure threshold of El mice correlates with the 5-HT concentration in the central nervous system. In this study, the anticonvulsant effect of a 5-HT reuptake blocker, citalopram, was evaluated behaviorally and biochemically. El mouse convulsions were inhibited by oral administration of citalopram for 2 weeks. Citalopram increased tryptophan and tyrosine amounts, and decreased the 5-HT, 5-hydroxyindoleacetic acid, kynurenine, and dopamine amounts in the brain. These findings show that citalopram depresses monoaminergic metabolism. Given the known convulsant effect of kynurenine, it is suggested that its decrease by citalopram may involve attenuation of El mice seizures.

The efficacy of selective serotonin re-uptake inhibitors in depression: a meta-analysis of studies against tricyclic antidepressants

A meta-analysis of the efficacy of five selective serotonin re-uptake inhibitors (SSRIs) against non-selective and noradrenergic re-uptake inhibitors (mainly tricyclic antidepressants, TCAs) is presented. Fifty five double- blind studies were identified after excluding those multiply reported or with methodological problems likely to bias the outcome in favour of SSRIs. Standardised effect sizes and 95% confidence intervals were calculated based on the difference in the reduction in mean Hamilton depression rating scale (HDRS) scores for the two antidepressants. For studies not reporting standard deviations, the pooled variance from complete studies was used and a variance-weighted mean effect size calculated. There were no differences in efficacy between SSRIs and comparator antidepressants for SSRIs taken together or individually. If studies were classified into high and low depression scores based on a median split of initial HDRS scores, there was a slight advantage to TCAs in the high HDRS group. In addition, SSRIs were slightly less effective than TCAs in in-patients and against combined serotonin and noradrenaline re-uptake inhibitors (clomipramine and amitriptyline). These findings were accounted for by a clinically significant lower efficacy of paroxetine in these subgroups. In contrast, SSRIs as a group were marginally more effective than noradrenergic antidepressants, a finding accounted for by two studies with sertraline. Fluvoxamine was the only SSRI to have been tested adequately in in-patients, where it displayed equal efficacy to TCAs. This meta-analysis confirms that SSRIs and TCAs are in general equally effective, but suggests that paroxetine's efficacy in in-patients and against clomipramine and amitriptyline is not proven.

A controlled multicenter clinical study of citalopram and placebo in elderly depressed patients with and without concomitant dementia

A total of 149 patients in 7 centers in Denmark, Norway and Sweden entered a 6-week double-blind trial intended to assess the antidepressant effect and safety of citalopram vs placebo in depressed elderly patients (65 years of age or older) who might also suffer from somatic disorders and/or senile dementia. Results of ratings on the Hamilton Rating Scale for Depression, the Montgomery-Asberg Depression Rating Scale and the Clinical Global Impression Scale provided consistent evidence that the citalopram-treated patients improved more than the placebo-treated patients. Results of ratings on the Gottfries-Bråne-Steen dementia rating scale indicated that both cognitive and emotional functioning improved significantly more in the citalopram-treated subgroup of patients with dementia than in the placebo-treated subgroup.

Comparative efficacy of antidepressants

Selective serotonin reuptake inhibitors (SSRIs) are a recently developed class of drugs with significantly greater antidepressant efficacy than placebo. Generally, in double-blind comparative trials, all SSRIs demonstrated antidepressant efficacy similar to that of the 'standard' tricyclic antidepressants amitriptyline and imipramine; a meta-analysis of controlled trials found the efficacy of the SSRIs to be equivalent to that of the 2 tricyclics. Nevertheless, because of small patient numbers included in most studies that compare SSRIs with other antidepressants, no definitive statements about relative efficacy can be made. In these studies it is simply possible to state that no statistically significant differences were identified between SSRIs and the comparative antidepressants. Importantly, differences in clinical characteristics exist between the SSRIs-differences in elimination half-life (t1/2 beta) between fluoxetine and/or its metabolite (total t1/2 beta = 330 hours) and other SSRIs (t1/2 beta range = 15 to 30 hours), for example. This has implications in terms of potential drug interactions and must be considered when patients have to be switched to treatment with monoamine oxidase inhibitors. Studies with fluvoxamine have been conducted in both in- and outpatients, whereas trials with other SSRIs have been confined largely to outpatient populations. Fluvoxamine has been associated with a high incidence of nausea (37%), although this may have resulted from high initial dosages (rather than upward dose titration protocols) used in early trials. Of further interest, fluoxetine doses of 20mg may be sufficient to produce a satisfactory antidepressant response, and this SSRI may be particularly useful in patients with chronic retarded depression. More clinical data are required before the efficacy of sertraline and citalopram relative to standard antidepressants can be clearly defined. Preliminary data indicate that SSRIs are effective in the treatment of panic disorder, obsessive-compulsive disorder (OCD), eating (e.g. anorexia and bulimia) and personality disorders (e.g. anger, impulsiveness) and substance abuse (e.g. alcoholism); early results with fluvoxamine in the treatment of panic disorder and OCD, and with fluoxetine in the treatment of bulimia, personality disorders and alcohol abuse, have been encouraging. SSRIs have a more favourable tolerability profile than tricyclic antidepressants and, unlike the tricyclics, are not associated with anticholinergic adverse effects, sedation, cardiotoxicity or weight gain. SSRIs are associated with a relatively high incidence of nausea, particularly if high doses are used at the start of treatment. However, the incidence of nausea appears to decrease as treatment is continued.(ABSTRACT TRUNCATED AT 400 WORDS)

Citalopram. A review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in depressive illness

Citalopram is an antidepressant belonging to a new class of drugs which enhance serotoninergic neurotransmission through potent and selective inhibition of serotonin reuptake. Preliminary trials suggest that its short term therapeutic efficacy is significantly greater than that of placebo and mianserin, and comparable to that of amitriptyline, maprotiline and imipramine. It appears to be a weaker antidepressant agent than clomipramine, but better tolerated. Its elimination half-life of 33 hours permits once daily oral administration. Symptomatic improvement obtained with short term treatment has been maintained when therapy has been extended for up to 1 year; in the few patients studied for this extended period, the relapse rate was lower than with fluvoxamine, fluoxetine or imipramine. Compared to standard antidepressant agents, citalopram is well tolerated. It does not appear to be cardiotoxic, has not been associated with seizures in humans, and is relatively nonsedating. Unlike the tricyclic antidepressants, citalopram has minimal anticholinergic effects. Mild and transient nausea, with or without vomiting, is the most frequent adverse effect--occurring in 20% of patients--and increased perspiration, headache, dry mouth, tremor and insomnia are experienced by 15 to 18% of patients. Citalopram thus offers similar therapeutic efficacy and a more favourable tolerability profile than the tricyclic antidepressants. Preliminary data suggest that it may be particularly useful in patients who cannot tolerate the anticholinergic or cardiovascular side effects of tricyclic antidepressants and in those for whom sedation is not indicated.

The clinical efficacy of citalopram in treatment of emotional disturbances in dementia disorders. A Nordic multicentre study

In this multicenter study, the clinical efficacy of citalopram was investigated in 98 patients with moderate AD/SDAT or VD using a combined double-blind and open technique with placebo and citalopram. Analyses were made for each diagnosis after four weeks of double-blind treatment. Patients with AD/SDAT treated with citalopram showed a significant improvement in emotional bluntness, confusion, irritability, anxiety, fear/panic, depressed mood and restlessness. Those improvements were not found after treatment with placebo. There were no significant improvements in patients with VD. No improvements were recorded in motor or cognitive impairment. Citalopram provoked few and comparatively mild side-effects. None of the changes observed during the double-blind withdrawal period were identified as withdrawal symptoms or rebound phenomena.