Methodological Flaws, Conflicts of Interest, and Scientific Fallacies: Implications for the Evaluation of Antidepressants' Efficacy and Harm

Schisandrol B alleviates depression-like behavior in mice by regulating bile acid homeostasis in the brain-liver-gut axis via the pregnane X receptor

BACKGROUND

Depression is a widely recognized neuropsychiatric disorder. Recent studies have shown a potential correlation between bile acid disorders and depression, highlighting the importance of maintaining bile acid balance for effective antidepressant treatment. Schisandrol B (SolB), a primary bioactive compound from Schisandra chinensis (Turcz.) Baill. or Schisandra sphenanthera Rehd.etWils, is pivotal in regulating bile acid homeostasis via pregnane X receptor (PXR) in cholestasis. However, the potential of SolB in alleviating depression-like symptoms, its pharmacological effects, and the underlying mechanisms remain to be fully elucidated.

METHODS

We confirmed the effect of SolB against depression induced by chronic restraint stress (CRS) and chronic unpredictable mild stress (CUMS) in mice. The role of SolB in bile acid homeostasis in depression was analyzed using the metabolomic. Gene analyses and 16S rRNA sequencing were employed to investigate the involvement of PXR. Experiments with Pxr-/- mice were conducted to confirm the essential role of the PXR pathway in SolB's antidepressant effects.

RESULTS

SolB treatment significantly increased sucrose consumption in the SPT and the locomotor activity in the OFT, while decreasing immobility time in the FST and TST in mice exposed to CRS and CUMS. Additionally, SolB treatment significantly preserved the integrity of the dendritic spine, elevated synaptic protein PSD95 levels, and augmented CREB/BDNF expression. Metabolomic and gene analyses indicated that SolB treatment significantly facilitated bile acid metabolism, promoted intestinal bile acid efflux, decreased hippocampal levels of the secondary bile acids DCA and TLCA, and upregulated expression of the PXR target proteins CYP3A11, SULT2A1, MRP2, and OATP1B1 in the liver, and MRP2 and MDR1 in hippocampus, which are integral to bile acid homeostasis. 16S rRNA sequencing revealed that SolB reduced the abundance of the bile salt hydrolase (BSH)-producing bacteria Lactobacillus johnsonii and Bacteroides fragilis and subsequently decreased the production of TLCA and DCA. Moreover, SolB failed to protect against depression induced by CRS in Pxr-null mice, suggesting that the antidepressant effect of SolB was PXR-dependent.

CONCLUSIONS

These results provide direct evidence of the antidepressant effect of SolB via activation of PXR to regulate bile acid homeostasis in the brain-liver-gut axis, suggesting that SolB may serve as a novel potential target for preventing and treating depression.

Association between duration of antidepressant treatment for major depressive disorder and relapse rate after discontinuation: A meta-analysis

The optimal duration of antidepressant treatment for patients with major depressive disorder to reduce the risk of relapse after discontinuation remains uncertain. Medline, Cochrane Central Register of Controlled Trials, and Embase were systematically searched for randomized controlled trials (RCTs) with a discontinuation design. A single-group summary meta-analysis was performed to calculate 6-month relapse rates after discontinuation. Meta-regression with restricted cubic splines was performed to model the non-linear relationship between treatment duration and relapse rate after discontinuation. Thirty-five RCTs were included. The relapse rate after discontinuation was approximately 34.81 % at 6 months and 45.12 % at 12 months. After controlling for covariates, the meta-analysis shows that the duration of treatment is associated with the risk of relapse after discontinuation in a non-linear curve, with a relatively higher risk of relapse observed for a duration of less than three months. There appears to be no further reduction in the risk of relapse when treatment is continued for over six months. Our results indicate the importance of at least three months of treatment to avoid the relatively high risk of relapse after discontinuation. The additional benefit of longer treatment remains to be proven.

Influence of study characteristics, methodological rigour and publication bias on efficacy of pharmacotherapy in obsessive-compulsive disorder: a systematic review and meta-analysis of randomised, placebo-controlled trials

QUESTION

We examined the effect of study characteristics, risk of bias and publication bias on the efficacy of pharmacotherapy in randomised controlled trials (RCTs) for obsessive-compulsive disorder (OCD).

STUDY SELECTION AND ANALYSIS

We conducted a systematic search of double-blinded, placebo-controlled, short-term RCTs with selective serotonergic reuptake inhibitors (SSRIs) or clomipramine. We performed a random-effect meta-analysis using change in the Yale-Brown Obsessive-Compulsive Scale (YBOCS) as the primary outcome. We performed meta-regression for risk of bias, intervention, sponsor status, number of trial arms, use of placebo run-in, dosing, publication year, age, severity, illness duration and gender distribution. Furthermore, we analysed publication bias using a Bayesian selection model.

FINDINGS

We screened 3729 articles and included 21 studies, with 4102 participants. Meta-analysis showed an effect size of -0.59 (Hedges' G, 95% CI -0.73 to -0.46), equalling a 4.2-point reduction in the YBOCS compared with placebo. The most recent trial was performed in 2007 and most trials were at risk of bias. We found an indication for publication bias, and subsequent correction for this bias resulted in a depleted effect size. In our meta-regression, we found that high risk of bias was associated with a larger effect size. Clomipramine was more effective than SSRIs, even after correcting for risk of bias. After correction for multiple testing, other selected predictors were non-significant.

CONCLUSIONS

Our findings reveal superiority of clomipramine over SSRIs, even after adjusting for risk of bias. Effect sizes may be attenuated when considering publication bias and methodological rigour, emphasising the importance of robust studies to guide clinical utility of OCD pharmacotherapy.

PROSPERO REGISTRATION NUMBER

CRD42023394924.

Investigation of Hypothalamic Pituitary Adrenal Axis and Oxytocinergic System Changes in a Pragmatic Randomized Controlled Feasibility Trial of Acupuncture for Antenatal Depression

Background: Antenatal depression is common and associated with detrimental impacts on women and their families. Disrupted neuroendocrine functioning is reported in women experiencing perinatal mental health disturbances. Preliminary randomized controlled trial (RCT) evidence suggests acupuncture may provide a safe and effective adjunct treatment; however, underlying mechanisms of effect are unclear. We conducted an RCT examination of acupuncture for the management of antenatal depressive symptomologies, which included oxytocinergic and hypothalamic pituitary adrenal (HPA) axis system evaluations. This article reports postintervention changes to cortisol: dehydroepiandrosterone (DHEA) ratios, and oxytocin (OT) hormone concentrations. Methods: Fifty-seven women with Edinburgh Postnatal Depression Scale (EPDS) scores ≥13 were randomized to receive individually tailored depressed specific acupuncture, progressive muscle relaxation (PMR) attention comparator, or treatment as usual (TAU). Weekly 1-h sessions were conducted for 8 weeks (24-31 of pregnancy). Preintervention and postintervention saliva samples were collected. Results: Postintervention mean cortisol: DHEA ratio differences were not significantly predicted by group allocation (n = 46, p = 0.065). Two-group comparisons demonstrated cortisol: DHEA ratios were significantly increased and predicted by group allocation when acupuncture was compared to TAU (p = 0.039); however, not between acupuncture and PMR (p = 0.179), or PMR and TAU (p = 0.421). Postintervention OT concentrations were not significantly predicted by group allocation. Limitations: Small sample size and posthoc analysis Conclusion: Findings suggest positive regulation of the HPA axis may be an underlying mechanism by which acupuncture provided the significant improvements to antenatal depression, stress, and distress observed in this cohort. Trial Registration: Registered on March 19, 2015, with the Australian New Zealand Clinical Trials Registry (ACTRN12615000250538).

No benefit of antidepressants in inpatient treatment of depression. A longitudinal, quasi-experimental field study

RATIONALE

Antidepressants (AD) are mostly considered indispensable for the treatment of major depression. The vast majority of depressive inpatients are treated with AD. However, there is a growing body of studies indicating that the effectiveness of AD is greatly overestimated due to methodological issues with the AD efficacy studies (e.g., publication bias, unintentional unblinding, confusion between withdrawal symptoms and relapse).

OBJECTIVES

The benefit of the additional use of AD in the inpatient treatment of depression with intensive cognitive-behavioral therapy (CBT) has been investigated in a naturalistic design.

METHODS

Depressiveness was assessed using the Beck Depression Inventory (BDI-II) during a preliminary interview (T0), at admission (T1), at discharge (T2), and at a 6-month follow-up (T3). Two study phases were compared: During Phase A, AD were recommended in accordance with the German guideline. In Phase B, AD were no longer recommended, and they were only prescribed upon explicit request from patients. In phase A (N = 574), 60.3% of all patients were taking AD at discharge. In Phase B (N = 424), 27.9% of patients were on AD at discharge. Apart from the difference in AD usage, the two treatment conditions were similar, and the samples did not significantly differ in terms of age, sex, diagnoses, history of suicide attempts, comorbid anxiety disorders, and unemployment.

RESULTS

In both study phases, BDI-II scores were strongly decreased at T2 and T3, respectively, compared with T1. The BDI-II scores of the two phases did not differ at any of the measurement time points. Depression changes were similar in both phases. In sequential multiple regression analyses with the total sample, AD were no significant predictors for the reduction of depression at either T2 or T3.

CONCLUSIONS

The inpatient CBT was effective in depression. The effectiveness of CBT is not improved by the additional use of AD. The current prescribing practices of AD should be questioned.

Associations between Pharmacological Treatment Patterns during the Initial Treatment Period and the Relapse or Recurrence of Anxiety Disorders: A Nationwide Retrospective Cohort Study

Although the importance of proper pharmacological treatment for preventing the relapse/recurrence of anxiety disorders is well known, a real-world data-based study has not been conducted. We aimed to investigate the effect of the initial pharmacological patterns related to continuous treatment and the choice of medication on the relapse/recurrence of anxiety disorders. We used claim data from the Health Insurance Review and Assessment Service, South Korea, of 34,378 adults who received psychiatric medications, including antidepressants, after being newly diagnosed with anxiety disorders. We compared the relapse/recurrence rate in the patients receiving continuous pharmacological treatment with those who discontinued treatment early using Cox's proportional-hazards model. Patients receiving continuous pharmacological treatment experienced a higher risk of relapse/recurrence than those who discontinued treatment. Using three or more antidepressants during the initial treatment period decreased the risk of relapse/recurrence (adjusted hazard ratio (aHR) = 0.229 (0.204-0.256)); however, the combined use of antidepressants from the beginning of treatment increased the risk (aHR = 1.215 (1.131-1.305)). Factors other than continuous pharmacological treatment should be considered to effectively prevent the relapse/recurrence of anxiety disorders. The active use of antidepressants, including switching or adding medications based on progress and frequent follow-up visits during the acute phase, were significantly associated with a reduction in the relapse/recurrence of anxiety disorders.

Biases in reporting of adverse effects in clinical trials, and potential impact on safety assessments in systematic reviews and therapy guidelines

BACKGROUND

Clinical trials are an important source of adverse effects data, including analyses in systematic reviews and recommendations in therapy guidelines. Trial publication bias may have profound effects on safety perceptions. This MiniReview presents and discusses biases in reporting of safety data in clinical trials and the implications for systematic reviews and guidelines.

OBJECTIVES

The objectives of this work are to analyse risk of gastrointestinal bleeding in systemic corticosteroid trials and to assess adverse effects reporting in a fluoxetine trial in depression (Treatment for Adolescents With Depression Study [TADS]) and descriptions of adverse effects in adolescent depression therapy guidelines.

METHODS

We performed literature reviews and descriptive analyse of clinical trials with corticosteroids, and publications from the TADS trial. Risk of gastrointestinal bleeding from corticosteroids was analysed by meta-analysis.

FINDINGS

Gastrointestinal bleeding definitions varied considerably between trials. The incidence was significantly increased in hospitalized, but not in ambulant, patients compared to placebo. We identified several biases concerning TADS safety reporting, including severity thresholds and nonpublication of most adverse effects data beyond the initial 12 weeks. Therapy guidelines on adolescent depression mentioned suicidality risk, but many failed to mention other adverse effects.

CONCLUSIONS

We identified several pitfalls in adverse effects reporting in clinical trials. These include heterogeneous disease definitions, reporting thresholds, and incomplete reporting. Trial bias may have great impact on risk assessments in systematic reviews and meta-analyses.

From contact coverage to effective coverage of community care for patients with severe mental disorders: A real-world investigation from Italy

OBJECTIVES

To measure the gap between contact and effective coverage of mental healthcare (MHC).

MATERIALS AND METHODS

45,761 newly referred cases of depression, schizophrenia, bipolar disorder, and personality disorder from four Italian regions were included. A variant of the self-controlled case series method was adopted to estimate the incidence rate ratio (IRR) for the relationship between exposure (i.e., use of different types of MHC such as pharmacotherapy, generic contact with the outpatient services, psychosocial intervention, and psychotherapy) and relapse (emergency hospital admissions for mental illness).

RESULTS

11,500 relapses occurred. Relapse risk was reduced during periods covered by (i) psychotherapy for patients with depression (IRR 0.67; 95% CI: 0.49 to 0.91) and bipolar disorder (0.64; 0.29 to 0.99); (ii) psychosocial interventions for those with depression (0.74; 0.56 to 0.98), schizophrenia (0.83; 0.68 to 0.99), and bipolar disorder (0.55; 0.36 to 0.84), (iii) pharmacotherapy for patients with schizophrenia (0.58; 0.49 to 0.69), and bipolar disorder (0.59; 0.44 to 0.78). Coverage with generic care, in absence of psychosocial/psychotherapeutic interventions, did not affect risk of relapse.

CONCLUSION

This study ascertained the gap between contact and effective coverage of MHC and showed that administrative data can usefully contribute to assess the effectiveness of a mental health system.

Not sad enough for a depression trial? A systematic review of depression measures and cut points in clinical trial registrations

INTRODUCTION

Patient reported outcomes are central to the evaluation of behavioral, drug, or somatic interventions focusing depression. Continuous measures are mostly interpreted with cut points that serve as inclusion criteria and define remission. The present review provides an overview of measures (BDI; BDI-II; CESD; HADS; HAMD-17; MADRS; PHQ-9; QIDS) and cut points in clinical trials on depression and tests for systematic differences concerning varying types of interventions.

METHODS

We analyzed 2632 trials registered via clinicaltrials.gov registered between 2000/01/01 - 2019/12/31 that used one or more pre-specified measures of depression of which 1600 reported cut points for either inclusion of participants or the definition of clinical remission.

RESULTS

The included studies more often used clinician-administered scales than self-report questionnaires as criterion for the inclusion of study participants and for the definition of clinical remission. Clinician administered scales are dominating in drug trials, while self-report questionnaires are primarily used in behavioral trials. This trend accelerated during the last 20 years. Compared to studies on behavioral therapies, studies with drug or other interventions used higher cut points to include patients. Comparisons between the interventions revealed highly significant differences in the used cut points of MADRS, HAMD-17 and PHQ-9.

CONCLUSIONS

Choice of measure and cut points is an important aspect of trial design and should be homogenized in order to make trials of different types of interventions more readily comparable. Similarly, systematic differences between treatment types in how patients are included and how remission is defined also hamper the comparisons between different treatment modalities.

Did the introduction and increased prescribing of antidepressants lead to changes in long-term trends of suicide rates?

Background

Ecological studies have explored associations between suicide rates and antidepressant prescriptions in the population, but most of them are limited as they analyzed short-term correlations that may be spurious. The aim of this long-term study was to examine whether trends in suicide rates changed in three European countries when the first antidepressants were introduced in 1960 and when prescription rates increased steeply after 1990 with the introduction of the serotonin reuptake inhibitors (SSRIs).

Methods

Data were extracted from the WHO Mortality Database. Suicide rates were calculated for people aged 10–89 years from 1951–2015 for Italy, 1955–2016 for Austria and 1951–2013 for Switzerland. Trends in suicide rates stratified by gender were analyzed using joinpoint regression models.

Results

There was a general pattern of long-term trends that was broadly consistent across all three countries. Suicide rates were stable or decreasing during the 1950s and 1960s, they rose during the 1970s, peaked in the early 1980s and thereafter they declined. There were a few notable exceptions to these general trends. In Italian men, suicide rates increased until 1997, then fell sharply until 2006 and increased again from 2006 to 2015. In women from all three countries, there was an extended period during the 2000s when suicide rates were stable. No trend changes occurred around 1960 or 1990.

Conclusions

The introduction of antidepressants around 1960 and the sharp increase in prescriptions after 1990 with the introduction of the SSRIs did not coincide with trend changes in suicide rates in Italy, Austria or Switzerland.

Approaches for discontinuation versus continuation of long-term antidepressant use for depressive and anxiety disorders in adults

BACKGROUND

Depression and anxiety are the most frequent indication for which antidepressants are prescribed. Long-term antidepressant use is driving much of the internationally observed rise in antidepressant consumption. Surveys of antidepressant users suggest that 30% to 50% of long-term antidepressant prescriptions had no evidence-based indication. Unnecessary use of antidepressants puts people at risk of adverse events. However, high-certainty evidence is lacking regarding the effectiveness and safety of approaches to discontinuing long-term antidepressants.

OBJECTIVES

To assess the effectiveness and safety of approaches for discontinuation versus continuation of long-term antidepressant use for depressive and anxiety disorders in adults.

SEARCH METHODS

We searched all databases for randomised controlled trials (RCTs) until January 2020.

SELECTION CRITERIA

We included RCTs comparing approaches to discontinuation with continuation of antidepressants (or usual care) for people with depression or anxiety who are prescribed antidepressants for at least six months. Interventions included discontinuation alone (abrupt or taper), discontinuation with psychological therapy support, and discontinuation with minimal intervention. Primary outcomes were successful discontinuation rate, relapse (as defined by authors of the original study), withdrawal symptoms, and adverse events. Secondary outcomes were depressive symptoms, anxiety symptoms, quality of life, social and occupational functioning, and severity of illness.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included 33 studies involving 4995 participants. Nearly all studies were conducted in a specialist mental healthcare service and included participants with recurrent depression (i.e. two or more episodes of depression prior to discontinuation). All included trials were at high risk of bias. The main limitation of the review is bias due to confounding withdrawal symptoms with symptoms of relapse of depression. Withdrawal symptoms (such as low mood, dizziness) may have an effect on almost every outcome including adverse events, quality of life, social functioning, and severity of illness. Abrupt discontinuation Thirteen studies reported abrupt discontinuation of antidepressant. Very low-certainty evidence suggests that abrupt discontinuation without psychological support may increase risk of relapse (hazard ratio (HR) 2.09, 95% confidence interval (CI) 1.59 to 2.74; 1373 participants, 10 studies) and there is insufficient evidence of its effect on adverse events (odds ratio (OR) 1.11, 95% CI 0.62 to 1.99; 1012 participants, 7 studies; I² = 37%) compared to continuation of antidepressants, without specific assessment of withdrawal symptoms. Evidence about the effects of abrupt discontinuation on withdrawal symptoms (1 study) is very uncertain. None of these studies included successful discontinuation rate as a primary endpoint. Discontinuation by "taper" Eighteen studies examined discontinuation by "tapering" (one week or longer). Most tapering regimens lasted four weeks or less. Very low-certainty evidence suggests that "tapered" discontinuation may lead to higher risk of relapse (HR 2.97, 95% CI 2.24 to 3.93; 1546 participants, 13 studies) with no or little difference in adverse events (OR 1.06, 95% CI 0.82 to 1.38; 1479 participants, 7 studies; I² = 0%) compared to continuation of antidepressants, without specific assessment of withdrawal symptoms. Evidence about the effects of discontinuation on withdrawal symptoms (1 study) is very uncertain. Discontinuation with psychological support Four studies reported discontinuation with psychological support. Very low-certainty evidence suggests that initiation of preventive cognitive therapy (PCT), or MBCT, combined with "tapering" may result in successful discontinuation rates of 40% to 75% in the discontinuation group (690 participants, 3 studies). Data from control groups in these studies were requested but are not yet available. Low-certainty evidence suggests that discontinuation combined with psychological intervention may result in no or little effect on relapse (HR 0.89, 95% CI 0.66 to 1.19; 690 participants, 3 studies) compared to continuation of antidepressants. Withdrawal symptoms were not measured. Pooling data on adverse events was not possible due to insufficient information (3 studies). Discontinuation with minimal intervention Low-certainty evidence from one study suggests that a letter to the general practitioner (GP) to review antidepressant treatment may result in no or little effect on successful discontinuation rate compared to usual care (6% versus 8%; 146 participants, 1 study) or on relapse (relapse rate 26% vs 13%; 146 participants, 1 study). No data on withdrawal symptoms nor adverse events were provided. None of the studies used low-intensity psychological interventions such as online support or a changed pharmaceutical formulation that allows tapering with low doses over several months. Insufficient data were available for the majority of people taking antidepressants in the community (i.e. those with only one or no prior episode of depression), for people aged 65 years and older, and for people taking antidepressants for anxiety.

AUTHORS' CONCLUSIONS

Currently, relatively few studies have focused on approaches to discontinuation of long-term antidepressants. We cannot make any firm conclusions about effects and safety of the approaches studied to date. The true effect and safety are likely to be substantially different from the data presented due to assessment of relapse of depression that is confounded by withdrawal symptoms. All other outcomes are confounded with withdrawal symptoms. Most tapering regimens were limited to four weeks or less. In the studies with rapid tapering schemes the risk of withdrawal symptoms may be similar to studies using abrupt discontinuation which may influence the effectiveness of the interventions. Nearly all data come from people with recurrent depression.   There is an urgent need for trials that adequately address withdrawal confounding bias, and carefully distinguish relapse from withdrawal symptoms. Future studies should report key outcomes such as successful discontinuation rate and should include populations with one or no prior depression episodes in primary care, older people, and people taking antidepressants for anxiety and use tapering schemes longer than 4 weeks.

Suicide risk with selective serotonin reuptake inhibitors and other new-generation antidepressants in adults: a systematic review and meta-analysis of observational studies

BACKGROUND

There is ongoing controversy whether antidepressant use alters suicide risk in adults with depression and other treatment indications.

METHODS

Systematic review of observational studies, searching MEDLINE, PsycINFO, Web of Science, PsycARTICLES and SCOPUS for case-control and cohort studies. We included studies on depression and various indications unspecified (including off-label use) reporting risk of suicide and/or suicide attempt for adult patients using selective serotonin reuptake inhibitors (SSRI) and other new-generation antidepressants relative to non-users. Effects were meta-analytically aggregated with random-effects models, reporting relative risk (RR) estimates with 95% CIs. Publication bias was assessed via funnel-plot asymmetry and trim-and-fill method. Financial conflict of interest (fCOI) was defined present when lead authors' professorship was industry-sponsored, they received industry-payments, or when the study was industry-sponsored.

RESULTS

We included 27 studies, 19 on depression and 8 on various indications unspecified (n=1.45 million subjects). SSRI were not definitely related to suicide risk (suicide and suicide attempt combined) in depression (RR=1.03, 0.70-1.51) and all indications (RR=1.19, 0.88-1.60). Any new-generation antidepressant was associated with higher suicide risk in depression (RR=1.29, 1.06-1.57) and all indications (RR=1.45, 1.23-1.70). Studies with fCOI reported significantly lower risk estimates than studies without fCOI. Funnel-plots were asymmetrical and imputation of missing studies with trim-and-fill method produced considerably higher risk estimates.

CONCLUSIONS

Exposure to new-generation antidepressants is associated with higher suicide risk in adult routine-care patients with depression and other treatment indications. Publication bias and fCOI likely contribute to systematic underestimation of risk in the published literature.

REGISTRATION

Open Science Framework, https://osf.io/eaqwn/.

Conditional power of antidepressant network meta-analysis

BACKGROUND

Conditional power of network meta-analysis (NMA) can support the planning of randomized controlled trials (RCTs) assessing medical interventions. Conditional power is the probability that updating existing inconclusive evidence in NMA with additional trial(s) will result in conclusive evidence, given assumptions regarding trial design, anticipated effect sizes, or event probabilities.

METHODS

The present work aimed to estimate conditional power for potential future trials on antidepressant treatments. Existing evidence was based on a published network of 502 RCTs conducted between 1979-2018 assessing acute antidepressant treatment in major depressive disorder (MDD). Primary outcomes were efficacy in terms of the symptom change on the Hamilton Depression Scale (HAMD) and tolerability in terms of the dropout rate due to adverse events. The network compares 21 antidepressants consisting of 231 relative treatment comparisons, 164 (efficacy) and 127 (tolerability) of which are currently assumed to have inconclusive evidence.

RESULTS

Required sample sizes to achieve new conclusive evidence with at least 80% conditional power were estimated to range between N = 894 - 4190 (efficacy) and N = 521 - 1246 (tolerability). Otherwise, sample sizes ranging between N = 49 - 485 (efficacy) and N = 40 - 320 (tolerability) may require stopping for futility based on a boundary at 20% conditional power. Optimizing trial designs by considering multiple trials that contribute both direct and indirect evidence, anticipating alternative effect sizes or alternative event probabilities, may increase conditional power but required sample sizes remain high. Antidepressants having the greatest conditional power associated with smallest required sample sizes were identified as those on which current evidence is low, i.e., clomipramine, levomilnacipran, milnacipran, nefazodone, and vilazodone, with respect to both outcomes.

CONCLUSIONS

The present results suggest that conditional power to achieve new conclusive evidence in ongoing or future trials on antidepressant treatments is low. Limiting the use of the presented conditional power analysis are primarily due to the estimated large sample sizes which would be required in future trials as well as due to the well-known small effect sizes in antidepressant treatments. These findings may inform researchers and decision-makers regarding the clinical relevance and justification of research in ongoing or future antidepressant RCTs in MDD.

Prophylactic effects or withdrawal reactions? An analysis of time-to-event data from antidepressant relapse prevention trials submitted to the FDA

BACKGROUND

Relapse prevention trials build the scientific foundation for recommendation of antidepressant continuation and maintenance therapy. However, the validity of the evidence is disputed and may be biased due to withdrawal confounding.

METHODS

We analysed survival curves from all antidepressant relapse prevention trials submitted to the United States (US) Food and Drug Administration (FDA) between 1987 and 2012 for 13 approved drugs. The main outcome was the percent of the drug effect (placebo-antidepressant difference in relapse events) at any week of the maintenance phase in relation to the total drug effect at the endpoint of the randomised maintenance phase.

RESULTS

Altogether, 14 studies with a mean observation period of 38.9 weeks (Kaplan-Meier estimators) were analysed. At week 3, a mean of 20.6% [95% confidence interval (CI) = 10.9-30.3%] of the total drug effect was achieved. At weeks 6 and 12, the corresponding figures were 50.3% (37.3-63.3%) and 69.0% (55.1-82.8%). No further antidepressant-placebo separation was observed as of week 24 [101.0% of total drug effect (94.6-107.3%)]. This means that censoring relapse events that occurred in the first 3, 6, 12 and 24 weeks would reduce the total drug effect at study endpoint by 20.6%, 50.3%, 69.0% and 101.0%, respectively. Assuming antidepressants had a constant prophylactic effect over 38.9 weeks, we further showed that, around week 6, the antidepressant-placebo separation was about three times larger than expected.

CONCLUSION

The placebo-antidepressant separation was disproportionally large between weeks 3 and 6 of the randomised maintenance phase. The benefits of continuing antidepressants relative to abrupt/rapid discontinuation declined sharply after week 6. This indicates an excess of relapse events in the placebo arms during the early maintenance phase that may be due to withdrawal reactions caused by abrupt/rapid discontinuation of active treatment. If these early relapse events are due to a direct pharmacological effect, then antidepressants' true prophylactic long-term effects are substantially overestimated.

The 'patient voice': patients who experience antidepressant withdrawal symptoms are often dismissed, or misdiagnosed with relapse, or a new medical condition

BACKGROUND

Stopping antidepressants commonly causes withdrawal symptoms, which can be severe and long-lasting. National Institute for Health and Care Excellence (NICE) guidance has been recently updated to reflect this; however, for many years withdrawal (discontinuation) symptoms were characterised as 'usually mild and self-limiting over a week'. Consequently, withdrawal symptoms might have been misdiagnosed as relapse of an underlying condition, or new onset of another medical illness, but this has never been studied.

METHOD

This paper outlines the themes emerging from 158 respondents to an open invitation to describe the experience of prescribed psychotropic medication withdrawal for petitions sent to British parliaments. The accounts include polypharmacy (mostly antidepressants and benzodiazepines) but we focus on antidepressants because of the relative lack of awareness about their withdrawal effects compared with benzodiazepines. Mixed method analysis was used, including a 'lean thinking' approach to evaluate common failure points.

RESULTS

The themes identified include: a lack of information given to patients about the risk of antidepressant withdrawal; doctors failing to recognise the symptoms of withdrawal; doctors being poorly informed about the best method of tapering prescribed medications; patients being diagnosed with relapse of the underlying condition or medical illnesses other than withdrawal; patients seeking advice outside of mainstream healthcare, including from online forums; and significant effects on functioning for those experiencing withdrawal.

DISCUSSION

Several points for improvement emerge: the need for updating of guidelines to help prescribers recognise antidepressant withdrawal symptoms and to improve informed consent processes; greater availability of non-pharmacological options for managing distress; greater availability of best practice for tapering medications such as antidepressants; and the vital importance of patient feedback. Although the patients captured in this analysis might represent medication withdrawal experiences that are more severe than average, they highlight the current inadequacy of health care systems to recognise and manage prescribed drug withdrawal, and patient feedback in general.

How effective are antidepressants for depression over the long term? A critical review of relapse prevention trials and the issue of withdrawal confounding

The aim of this article is to discuss the validity of relapse prevention trials and the issue of withdrawal confounding in these trials. Recommendations for long-term antidepressant treatment are based almost exclusively on discontinuation trials. In these relapse prevention trials, participants with remitted depression are randomised either to have the antidepressant abruptly discontinued and replaced by inert placebo or to continue active treatment. The drug-placebo difference in relapse rates at the end of the maintenance phase is then interpreted as a prophylactic drug effect. These trials consistently produce remarkable benefits for maintenance treatment. However, the internal validity of this trial protocol is compromised, as research has shown that abruptly stopping antidepressants can cause severe withdrawal reactions that lead to (or manifest as) depression relapses. That is, there is substantial withdrawal confounding in discontinuation trials, which renders their findings uninterpretable. It is not clear to what degree the drug-placebo separation in relapse prevention (discontinuation) trials is due to withdrawal reactions, but various estimations suggest that it is presumably the majority. A review of findings based on other methodologies, including real-world long-term effectiveness trials like STAR*D and various naturalistic cohort studies, do not indicate that antidepressants have considerable prophylactic effects. As absence of evidence does not imply evidence of absence, no definitive conclusions can be drawn from the literature. To enable a thorough risk-benefit evaluation, real-world effectiveness trials should not only focus on relapse prevention, but also assess antidepressants' long-term effects on social functioning and quality of life. Thus far, reliable long-term data on these outcome domains are lacking.

Raising Placebo Efficacy in Antidepressant Trials Across Decades Explained by Small-Study Effects: A Meta-Reanalysis

BACKGROUND

Recent meta-analyses reported placebo response rate in antidepressant trials to be stable since the 1970s. These meta-analyses however were limited in considering only linear time trends, assessed trial-level covariates based on single-model hypothesis testing only, and did not adjust for small-study effects (SSE), a well-known but not yet formally assessed bias in antidepressant trials.

METHODS

This secondary meta-analysis extends previous work by modeling nonlinear time trends, assessing the relative importance of trial-level covariates using a multimodel approach, and rigorously adjusting for SSE. Outcomes were placebo efficacy (continuous), based on the Hamilton Depression Scale, and placebo response rate.

RESULTS

Results suggested that any nonlinear time trends in both placebo efficacy (continuous) and response rate were best explained by SSE. Adjusting for SSE revealed a significant gradual increase in placebo efficacy (continuous) from 1979 to 2014. A similar observation was made for placebo response rate, but did not reach significance due higher susceptibility to SSE. By contrast, trial-level covariates alone were found to be insufficient in explaining time trends.

CONCLUSION

The present findings contribute to the ongoing debate on antidepressant placebo outcomes and highlight the need to adjust for bias introduced by SSE. The results are of clinical relevance because SSE may affect the evaluation of success or failure in antidepressant trials.

Prevalence and Determinants of Long-Term Utilization of Antidepressant Drugs: A Retrospective Cohort Study

PURPOSE

Antidepressant consumption has risen in recent years, driven by longer treatment duration. The objective of this study was to measure the prevalence of antidepressant long-term and chronic use in the Bologna area, Italy, and to identify their main determinants.

MATERIALS AND METHODS

We conducted a retrospective claims-based cohort study by using the Bologna Local Health Authority data. A cohort of 18,307 incident users of antidepressant drugs in 2013 was selected, and subjects were followed for three years. A long-term utilization was defined as having at least one prescription claimed during each year of follow-up, while chronic utilization was defined as claiming at least 180 defined daily doses per year. Factors associated with chronic and long-term use were identified by univariate and multivariate logistic regressions.

RESULTS

In our cohort, 5448 (29.8%) and 1817 (9.9%) subjects were dispensed antidepressants for a long-term course and in a chronically way, respectively. Older age, antidepressant polytherapy, polypharmacy, and being prescribed the first antidepressant by a hospital physician were all factors independently associated with chronic and long-term prescriptions of antidepressant drugs. Results were reported separately for men and women.

CONCLUSION

Antidepressant long-term and chronic prescriptions are common in the Bologna area. Because longer treatment should be clinically motivated, these results strongly prompt the need to evaluate the actual relevance, as they may indicate potentially inappropriate prescription patterns.

Protracted withdrawal syndrome after stopping antidepressants: a descriptive quantitative analysis of consumer narratives from a large internet forum

BACKGROUND

Protracted withdrawal syndrome (PWS) after stopping antidepressants (frequently also referred to as post-acute withdrawal syndrome or PAWS) has been described in a few case reports. However, a detailed quantitative analysis of specific symptom manifestations in antidepressant PWS is still lacking.

METHODS

We extracted patient narratives from a large English-language internet forum SurvivingAntidepressants.org, a peer support site concerned about withdrawal from antidepressants. PWS was ascertained based on diagnostic criteria proposed by Chouinard and Chouinard, specifically ⩾6 months of continuous antidepressant use, with emergence of new and/or more intense symptoms after discontinuation that last beyond the initial 6 weeks of acute withdrawal. We assessed medication history, outcome of PWS, and the prevalence of specific symptoms.

RESULTS

In total, n = 69 individual reports of protracted withdrawal were selected for analysis. At time of the subjects' most recent reports, duration of PWS ranged from 5 to 166 months, mean = 37 months, median = 26 months. Length of time on the antidepressant causing protracted withdrawal ranged from 6 to 278 months, mean = 96 months, and median = 79 months. Throughout the withdrawal experience, affective symptoms, mostly anxiety, depression, emerging suicidality and agitation, were reported by 81%. Somatic symptoms, mostly headache, fatigue, dizziness, brain zaps, visual changes, muscle aches, tremor, diarrhea, and nausea were reported by 75%. Sleep problems (44%) and cognitive impairments (32%) were mentioned less frequently. These broad symptom domains were largely uncorrelated.

CONCLUSION

PWS or PAWS from antidepressants can be severe and long-lasting, and its manifestations clinically heterogeneous. Long-term antidepressant exposure may cause multiple body system impairments. Although both somatic and affective symptoms are frequent, they are mostly unrelated in terms of occurrence. Proper recognition and detection of PWS thus requires a comprehensive assessment of medication history, duration of the withdrawal syndrome, and its various somatic, affective, sleep, and cognitive symptoms.

[Exercise for depression treatment. Physiological mechanisms]

This literature review considers meta-analyzes, systematic reviews and original research over the last decade addressing a comprehensive analysis of the antidepressant effect of targeted physical exercise and physical activity in general. Exercise is a promising non-pharmacological treatment for depression, showing effects that are comparable or may even exceed other first-line treatments of depression. The article introduces modern ideas about the mechanisms of depression and mechanisms of exercise effects on depression manifestations. The structures of the central nervous system, changing with the effective exercise-based treatment of depression, are indicated. Physical activity stimulates the secretion of growth factors, maintenance of angio-, synapto-, and neurogenesis. The regulation of antioxidant protection of neuronal mitochondria, a decrease in pro-inflammatory reactions and stress reactivity are also observed in response to regular exercise. Physical activity has a multimodal effect that stimulates biochemical pathways and restores neuronal structures disturbed in depression.

[Exercise for depression treatment. Exercise modalities and types]

The risk of metabolic disorders, including type 2 diabetes and cardiovascular diseases, is increased in depression, there is a decrease in life expectancy by 8-10 years. Pharmacotherapy is the first-line method in the treatment of depression. However, pharmaceutical-related side-effects and resistance to antidepressant pharmacotherapy create serious problems in treatment. Regular exercise not only weakens the symptoms of depression, increases aerobic capacity and muscle strength, but also has a positive effect on comorbid diseases. The purpose of this review is to answer the question, on which parameters of exercise the antidepressant effect depends. The review highlights the results of clinical studies of different types of exercises, intensities and modalities for the treatment of depression over the past 10 years. Because of the contradictory results of the studies, it is impossible to make final conclusions regarding the parameters of exercise. It is possible to say with high probability that in the treatment of depression, moderate and intense aerobic exercises with elements of strength exercises and a variety of coordination exercises more often lead to a positive effect than monotonous exercises with low intensity. It is possible that regular patient adherence to the prescribed exercise regimen is more important than the specific exercise type.

Guidelines for the pharmacological acute treatment of major depression: conflicts with current evidence as demonstrated with the German S3-guidelines

Several international guidelines for the acute treatment of moderate to severe unipolar depression recommend a first-line treatment with antidepressants (AD). This is based on the assumption that AD obviously outperform placebo, at least in the case of severe depression. The efficacy of AD for severe depression can only be definitely clarified with individual patient data, but corresponding studies have only been available recently. In this paper, we point out discrepancies between the content of guidelines and the scientific evidence by taking a closer look at the German S3-guidelines for the treatment of depression. Based on recent studies and a systematic review of studies using individual patient data, it turns out that AD are marginally superior to placebo in both moderate and severe depression. The clinical significance of this small drug-placebo-difference is questionable, even in the most severe forms of depression. In addition, the modest efficacy is likely an overestimation of the true efficacy due to systematic method biases. There is no related discussion in the S3-guidelines, despite substantial empirical evidence confirming these biases. In light of recent data and with their underlying biases, the recommendations in the S3-guidelines are in contradiction with the current evidence. The risk-benefit ratio of AD for severe depression may be similar to the one estimated for mild depression and thus could be unfavorable. Downgrading of the related grade of recommendation would be a logical consequence.

Scientific debate instead of beef; challenging misleading arguments about the efficacy of antidepressants

In a recent commentary with the polemic title 'Antidepressants; what's the beef?', Goodwin and Nutt argued that the benefit-risk ratio of antidepressants had been questioned inappropriately (Goodwin & Nutt, 2019). Personally I think it is a great achievement that our medical system can offer pharmacological treatments to people who suffer from serious clinical depression, and like Goodwin and Nutt I accept that antidepressants may be useful in some patients (Hengartner & Plöderl, 2018). Nevertheless, and this is where my position deviates from Goodwin and Nutt, I am also concerned about the overestimation of efficacy and the minimisation of harm (Hengartner, 2017). There are many misrepresentations in the commentary by Goodwin and Nutt, all of which systematically inflate the apparent benefits of antidepressants, and in this letter, I will discuss five of them.

Considering the methodological limitations in the evidence base of antidepressants for depression: a reanalysis of a network meta-analysis

OBJECTIVES

To investigate whether the conclusion of a recent systematic review and network meta-analysis (Cipriani et al) that antidepressants are more efficacious than placebo for adult depression was supported by the evidence.

DESIGN

Reanalysis of a systematic review, with meta-analyses.

DATA SOURCES

522 trials (116 477 participants) as reported in the systematic review by Cipriani et al and clinical study reports for 19 of these trials.

ANALYSIS

We used the Cochrane Handbook's risk of bias tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to evaluate the risk of bias and the certainty of evidence, respectively. The impact of several study characteristics and publication status was estimated using pairwise subgroup meta-analyses.

RESULTS

Several methodological limitations in the evidence base of antidepressants were either unrecognised or underestimated in the systematic review by Cipriani et al. The effect size for antidepressants versus placebo on investigator-rated depression symptom scales was higher in trials with a 'placebo run-in' study design compared with trials without a placebo run-in design (p=0.05). The effect size of antidepressants was higher in published trials compared with unpublished trials (p<0.0001). The outcome data reported by Cipriani et al differed from the clinical study reports in 12 (63%) of 19 trials. The certainty of the evidence for the placebo-controlled comparisons should be very low according to GRADE due to a high risk of bias, indirectness of the evidence and publication bias. The mean difference between antidepressants and placebo on the 17-item Hamilton depression rating scale (range 0-52 points) was 1.97 points (95% CI 1.74 to 2.21).

CONCLUSIONS

The evidence does not support definitive conclusions regarding the benefits of antidepressants for depression in adults. It is unclear whether antidepressants are more efficacious than placebo.

Depressive disorders: Treatment failures and poor prognosis over the last 50 years

Depression like many diseases is pleiotropic but unlike cancer and Alzheimer's disease for example, is still largely stigmatized and falls into the dark shadows of human illness. The failure of depression to be in the spotlight for successful treatment options is inherent in the complexity of the disease(s), flawed clinical diagnosis, overgeneralization of the illness, inadequate and biased clinical trial design, restrictive and biased inclusion/exclusion criteria, lack of approved/robust biomarkers, expensive imaging technology along with few advances in neurobiological hypotheses in decades. Clinical trial studies summitted to the regulatory agencies (FDA/EMA) for approval, have continually failed to show significant differences between active and placebo. For decades, we have acknowledged this failure, despite vigorous debated by all stakeholders to provide adequate answers to this escalating problem, with only a few new antidepressants approved in the last 20 years with equivocal efficacy, little improvement in side effects or onset of efficacy. It is also clear that funding and initiatives for mental illness lags far behind other life-treating diseases. Thus, it is no surprise we have not achieved much success in the last 50 years in treating depression, but we are accountable for the many failures and suboptimal treatment. This review will therefore critically address where we have failed and how future advances in medical science offers a glimmer of light for the patient and aid our future understanding of the neurobiology and pathophysiology of the disease, enabling transformative therapies for the treatment of depressive disorders.

Antidepressant Use During Acute Inpatient Care Is Associated With an Increased Risk of Psychiatric Rehospitalisation Over a 12-Month Follow-Up After Discharge

Background: Some evidence suggests that antidepressants may relate to poor outcomes in depression. The aim of this study was, therefore, to examine, whether antidepressant use may worsen the long-term outcome in real-world psychiatric patients with both primarily affective and non-affective mental disorders. Methods: Based on a total of n = 151 inpatients with a mixed range of diagnoses enrolled at two psychiatric hospitals in Zurich, Switzerland, matched pairs of n = 45 antidepressant users and n = 45 non-users were selected via nearest neighbor propensity score matching. Pairs were matched according to 14 clinically relevant covariates assessing psychosocial impairments, functioning deficits and illness severity. The two outcomes of interest were the number and total duration of all rehospitalisations over a 12-month follow-up after discharge from the hospital based on the official clinical registry. Results: Altogether 35.6% of antidepressant users were rehospitalised at least once, as compared to 22.2% in matched non-users. Two or more rehospitalisations occurred in 22.2% of antidepressant users but only in 2.2% of non-users. In antidepressant users, the mean total duration of rehospitalisations was 22.22 days, as compared to 8.51 in matched non-users. According to Poisson regression analyses, antidepressant use during acute inpatient care prospectively relates to both a higher risk (incidence rate ratio [IRR] = 3.64, 95% confidence interval [95%-CI] = 1.71-7.75, p = 0.001) and a longer duration (IRR = 2.61, 95%-CI = 1.01-6.79, p = 0.049) of subsequent rehospitalisations. These findings were consistently replicated when traditional multivariable regression analysis was applied to the full sample. Findings also replicated when patients with affective and non-affective disorders were analyzed separately. Conclusions: Our findings raise the possibility that, in the long-term, antidepressants may impair recovery and increase the risk of rehospitalisation in patients with both primarily affective and non-affective disorders. More work is required to explore possible aetiopathological pathways leading to psychiatric rehospitalisation.

Short- and Long-Term Antidepressant Clinical Trials for Major Depressive Disorder in Youth: Findings and Concerns

The diagnosis of major depressive disorder (MDD) in U.S. youth is increasing as is the rate of antidepressant medication (ADM) treatment for the disorder. Fluoxetine and escitalopram are FDA approved for the short term and maintenance treatment of MDD in youth. Placebo-controlled short-term ADM trials represent the basis for Food and Drug Administration (FDA) approval. Meta-analyses in 2007 and 2016 revealed that short-term ADM treatment of youth diagnosed with MDD resulted in no meaningful benefit for children and only marginal benefit for adolescents. Placebo substitution trials of ADM short-term responders represent the basis for FDA approval of ADM maintenance treatment. These ADM placebo substitution maintenance trials for youth with MDD are characterized by high dropout rates, a rapid withdrawal that often can follow the switch to placebo, and relapse rates that are not dissimilar from those in the natural course of the disorder. Without the evidence from problematic ADM placebo substitution trials, there is no acceptable support for the inclusion of ADM in maintenance treatment for MDD in youth.

Inhibition of Phosphodiesterase 4 by FCPR03 Alleviates Chronic Unpredictable Mild Stress-Induced Depressive-Like Behaviors and Prevents Dendritic Spine Loss in Mice Hippocampi

BACKGROUND

Phosphodiesterase 4 is a promising target for developing novel antidepressants. However, prototype phosphodiesterase 4 inhibitors show severe side effects, including nausea and vomiting. N-Isopropyl-3-(cyclopropylmethoxy)-4-difluoromethoxy benzamide (FCPR03) is a novel phosphodiesterase 4 inhibitor with little emetic potential. In the present study, we investigated the inhibitory effect of FCPR03 on chronic unpredictable mild stress-induced, depressive-like behaviors in mice and explored the underlying mechanisms.

METHODS

The depression model of mice was established by chronic unpredictable mild stress. Forced swim test, tail suspension test, and sucrose preference test were used to assess depressive-like behaviors. Golgi-staining was utilized to analyze dendritic morphology and spine density. The level of cAMP was measured by enzyme-linked immnosorbent assay assay. Western blot was used to evaluate protein levels of phosphorylated cAMP-response element binding protein, protein kinase B, glycogen synthase kinase-3β, and brain derived neurotrophic factor in both hippocampus and prefrontal cortex. Postsynaptic density protein 95 and synapsin 1 were also detected by western blot in the hippocampi.

RESULTS

Treatment with FCPR03 (0.5-1.0 mg/kg, i.p.) increased consumption of sucrose in the sucrose preference test in mice exposed to chronic unpredictable mild stress. FCPR03 shortened the immobility time in forced swim test and tail suspension test without affecting locomotor activity. Furthermore, chronic unpredictable mild stress decreased the dendritic spine density and dendritic length in the hippocampus. This change was accompanied by decreased expression of postsynaptic density protein 95 and synapsin 1. Interestingly, FCPR03 prevented dendritic spine loss and increased synaptic protein levels. Moreover, the levels of cAMP, phosphorylated cAMP-response element binding protein, and brain derived neurotrophic factor were elevated in chronic unpredictable mild stress-challenged mice after treatment with FCPR03. In addition, FCPR03 also enhanced the phosphorylation of both protein kinase B and glycogen synthase kinase-3β in mice exposed to chronic unpredictable mild stress.

CONCLUSION

The present study suggests that FCPR03 could prevent both depressive-like behaviors and spine loss induced by chronic unpredictable mild stress in the mice hippocampi.