Consistent superiority of selective serotonin reuptake inhibitors over placebo in reducing depressed mood in patients with major depression

Relating ASD symptoms to well-being: moving across different construct levels

BACKGROUND

Little is known about the specific factors that contribute to the well-being (WB) of individuals with autism spectrum disorder (ASD). A plausible hypothesis is that ASD symptomatology has a direct negative effect on WB. In the current study, the emerging tools of network analysis allow to explore the functional interdependencies between specific symptoms of ASD and domains of WB in a multivariate framework. We illustrate how studying both higher-order (total score) and lower-order (subscale) representations of ASD symptomatology can clarify the interrelations of factors relevant for domains of WB.

METHODS

We estimated network structures on three different construct levels for ASD symptomatology, as assessed with the Adult Social Behavior Questionnaire (item, subscale, total score), relating them to daily functioning (DF) and subjective WB in 323 adult individuals with clinically identified ASD (aged 17-70 years). For these networks, we assessed the importance of specific factors in the network structure.

RESULTS

When focusing on the highest representation level of ASD symptomatology (i.e. a total score), we found a negative connection between ASD symptom severity and domains of WB. However, zooming in on lower representation levels of ASD symptomatology revealed that this connection was mainly funnelled by ASD symptoms related to insistence on sameness and experiencing reduced contact and that those symptom scales, in turn, impact different domains of WB.

CONCLUSIONS

Zooming in across construct levels of ASD symptom severity into subscales of ASD symptoms can provide us with important insights into how specific domains of ASD symptoms relate to specific domains of DF and WB.

A Systematic Review of the Clinimetric Properties of the 6-Item Version of the Hamilton Depression Rating Scale (HAM-D6)

BACKGROUND

In a study aimed at identifying the items carrying information regarding the global severity of depression, the 6-item Hamilton Depression Rating Scale (HAM-D6) was derived from the original 17-item version of the scale (HAM-D17). Since then, the HAM-D6 has been used in a wide range of clinical studies. We now provide a systematic review of the clinimetric properties of HAM-D6 in comparison with those of HAM-D17 and the Montgomery Asberg Depression Rating Scale (MADRS).

METHODS

We conducted a systematic search of the literature in PubMed, PsycInfo, and EMBASE databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Studies reporting data on the clinimetric validity of the HAM-D6 and either the HAM-D17 or MADRS in non-psychotic unipolar or bipolar depression were included in the synthesis.

RESULTS

The search identified 681 unique records, of which 51 articles met the inclusion criteria. According to the published literature, HAM-D6 has proven to be superior to both HAM-D17 and MADRS in terms of scalability (each item contains unique information regarding syndrome severity), transferability (scalability is constant over time and irrespective of sex, age, and depressive subtypes), and responsiveness (sensitivity to change in severity during treatment).

CONCLUSIONS

According to the published literature, the clinimetric properties of HAM-D6 are superior to those of both the HAM-D17 and MADRS. Since the validity of HAM-D6 has been demonstrated in both research and clinical practice, using the scale more consistently would facilitate translation of results from one setting to the other.

Individual biological sensitivity to environmental influences: testing the differential susceptibility properties of the 5HTTLPR polymorphism in relation to depressive symptoms and delinquency in two adolescent general samples

The gene–environment interaction research field in psychiatry has traditionally been dominated by the diathesis–stress framework, where certain genotypes are assumed to confer increased risk for adverse outcomes in a stressful environment. In later years, theories of differential susceptibility, or biological sensitivity, suggest that candidate genes that interact with environmental events do not exclusively confer a risk for behavioural or psychiatric disorders but rather seem to alter the sensitivity to both positive and negative environmental influences. The present study investigates the susceptibility properties of the serotonin transporter-linked polymorphic region (5HTTLPR) in relation to depressive symptoms and delinquency in two separate adolescent community samples: n = 1457, collected in 2006; and n = 191, collected in 2001. Two-, three-, and four-way interactions between the 5HTTLPR, positive and negative family environment, and sex were found in relation to both depressive symptoms and delinquency. However, the susceptibility properties of the 5HTTLPR were distinctly less pronounced in relation to depressive symptoms. If the assumption that the 5HTTLPR induces differential susceptibility to both positive and negative environmental influences is correct, the previous failures to measure and control for positive environmental factors might be a possible explanation for former inconsistent findings within the research field.

Longitudinal network structure of depression symptoms and self-efficacy in low-income mothers

Maternal depression was recently conceptualized as a network of interacting symptoms. Prior studies have shown that low self-efficacy, as an index of maternal functioning, is one important source of stress that worsens depression. We have limited information, however, on the specific relationships between depression symptoms and self-efficacy. In this study, we used regularized partial correlation networks to explore the multivariate relationships between maternal depression symptoms and self-efficacy over time. Depressed mothers (n = 306) completed the Center for Epidemiological Studies Depression (CES-D) scale at four time points, between four and eight weeks apart. We estimated (a) the network structure of the 20 CES-D depression symptoms and self-efficacy for each time point, (b) determined the centrality or structural importance of all variables, and (c) tested whether the network structure changed over time. In the resulting networks, self-efficacy was mostly negatively connected with depression symptoms. The strongest relationships among depression symptoms were 'lonely-sleep difficulties' and 'inability to get going-crying'. 'Feeling disliked' and 'concentration difficulty' were the two most central symptoms. In comparing the network structures, we found that the network structures were moderately stable over time. This is the first study to investigate the network structure and their temporal stability of maternal depression symptoms and self-efficacy in low-income depressed mothers. We discuss how these findings might help future research to identify clinically relevant symptom-to-symptom relationships that could drive maternal depression processes, and potentially inform tailored interventions. We share data and analytical code, making our results fully reproducible.

Association of the Polygenic Scores for Personality Traits and Response to Selective Serotonin Reuptake Inhibitors in Patients with Major Depressive Disorder

Studies reported a strong genetic correlation between the Big Five personality traits and major depressive disorder (MDD). Moreover, personality traits are thought to be associated with response to antidepressants treatment that might partly be mediated by genetic factors. In this study, we examined whether polygenic scores (PGSs) derived from the Big Five personality traits predict treatment response and remission in patients with MDD who were prescribed selective serotonin reuptake inhibitors (SSRIs). In addition, we performed meta-analyses of genome-wide association studies (GWASs) on these traits to identify genetic variants underpinning the cross-trait polygenic association. The PGS analysis was performed using data from two cohorts: the Pharmacogenomics Research Network Antidepressant Medication Pharmacogenomic Study (PGRN-AMPS, n = 529) and the International SSRI Pharmacogenomics Consortium (ISPC, n = 865). The cross-trait GWAS meta-analyses were conducted by combining GWAS summary statistics on SSRIs treatment outcome and on the personality traits. The results showed that the PGS for openness and neuroticism were associated with SSRIs treatment outcomes at p < 0.05 across P_T thresholds in both cohorts. A significant association was also found between the PGS for conscientiousness and SSRIs treatment response in the PGRN-AMPS sample. In the cross-trait GWAS meta-analyses, we identified eight loci associated with (a) SSRIs response and conscientiousness near YEATS4 gene and (b) SSRI remission and neuroticism eight loci near PRAG1, MSRA, XKR6, ELAVL2, PLXNC1, PLEKHM1, and BRUNOL4 genes. An assessment of a polygenic load for personality traits may assist in conjunction with clinical data to predict whether MDD patients might respond favorably to SSRIs.

PTSD symptomics: network analyses in the field of psychotraumatology

Recent years have seen increasing attention on posttraumatic stress disorder (PTSD) research. While research has largely focused on the dichotomy between patients diagnosed with mental disorders and healthy controls - in other words, investigations at the level of diagnoses - recent work has focused on psychopathology symptoms. Symptomics research in the area of PTSD has been scarce so far, although several studies have focused on investigating the network structures of PTSD symptoms. The present special issue of EJPT adds to the literature by curating additional PTSD network studies, each looking at a different aspect of PTSD. We hope that this special issue encourages researchers to conceptualize and model PTSD data from a network perspective, which arguably has the potential to inform and improve the efficacy of therapeutic interventions.

Reactivity to unpredictable threat as a treatment target for fear-based anxiety disorders

BACKGROUND

Heightened reactivity to unpredictable threat (U-threat) is a core individual difference factor underlying fear-based psychopathology. Little is known, however, about whether reactivity to U-threat is a stable marker of fear-based psychopathology or if it is malleable to treatment. The aim of the current study was to address this question by examining differences in reactivity to U-threat within patients before and after 12-weeks of selective serotonin reuptake inhibitors (SSRIs) or cognitive-behavioral therapy (CBT).

METHODS

Participants included patients with principal fear (n = 22) and distress/misery disorders (n = 29), and a group of healthy controls (n = 21) assessed 12-weeks apart. A well-validated threat-of-shock task was used to probe reactivity to predictable (P-) and U-threat and startle eyeblink magnitude was recorded as an index of defensive responding.

RESULTS

Across both assessments, individuals with fear-based disorders displayed greater startle magnitude to U-threat relative to healthy controls and distress/misery patients (who did not differ). From pre- to post-treatment, startle magnitude during U-threat decreased only within the fear patients who received CBT. Moreover, within fear patients, the magnitude of decline in startle to U-threat correlated with the magnitude of decline in fear symptoms. For the healthy controls, startle to U-threat across the two time points was highly reliable and stable.

CONCLUSIONS

Together, these results indicate that startle to U-threat characterizes fear disorder patients and is malleable to treatment with CBT but not SSRIs within fear patients. Startle to U-threat may therefore reflect an objective, psychophysiological indicator of fear disorder status and CBT treatment response.

Incidence of early anxiety aggravation in trials of selective serotonin reuptake inhibitors in depression

OBJECTIVE

Selective serotonin reuptake inhibitors (SSRIs) may aggravate anxiety and agitation during the first days of treatment but the frequency of such reactions remains unknown.

METHOD

We analysed patient-level data from placebo-controlled trials of sertraline, paroxetine or citalopram in depressed adults. Somatic anxiety, psychic anxiety and psychomotor agitation as assessed using the Hamilton Depression Rating Scale (HDRS) were analysed in all trials (n = 8262); anxiety-related adverse events were analysed in trials investigating paroxetine and citalopram (n = 5712).

RESULTS

After one but not two weeks, patients on an SSRI were more likely than those on placebo to report enhanced somatic anxiety (adjusted risk 9.3% vs. 6.7%); likewise, mean rating of somatic anxiety was higher in the SSRI group. In contrast, patients receiving an SSRI were less likely to report aggravation of psychic anxiety (adjusted risk: 7.0% vs. 8.5%) with mean rating of psychic anxiety and agitation being lower in the SSRI group. The adverse event 'nervousness' was more common in patients given an SSRI (5.5% vs. 2.5%). Neither aggravation of HDRS-rated anxiety nor anxiety-related adverse events predicted poor antidepressant response.

CONCLUSION

Whereas an anxiety-reducing effect of SSRIs is notable already during the first week of treatment, these drugs may also elicit an early increase in anxiety in susceptible subjects that however does not predict a poor subsequent response to treatment.

Do You Believe It? Verbal Suggestions Influence the Clinical and Neural Effects of Escitalopram in Social Anxiety Disorder: A Randomized Trial

Background

Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed for depression and anxiety, but their efficacy relative to placebo has been questioned. We aimed to test how manipulation of verbally induced expectancies, central for placebo, influences SSRI treatment outcome and brain activity in patients with social anxiety disorder (SAD).

Methods

We did a randomized clinical trial, within an academic medical center (Uppsala, Sweden), of individuals fulfilling the DSM-IV criteria for SAD, recruited through media advertising. Participants were 18 years or older and randomized in blocks, through a computer-generated sequence by an independent party, to nine weeks of overt or covert treatment with escitalopram (20 mg daily). The overt group received correct treatment information whereas the covert group was treated deceptively with the SSRI described, by the psychiatrist, as active placebo. The treating psychiatrist was necessarily unmasked while the research staff was masked from intervention assignment. Treatment efficacy was assessed primarily with the self-rated Liebowitz Social Anxiety Scale (LSAS-SR), administered at week 0, 1, 3, 6 and 9, also yielding a dichotomous estimate of responder status (clinically significant improvement). Before and at the last week of treatment, brain activity during an emotional face-matching task was assessed with functional magnetic resonance imaging (fMRI) and during fMRI sessions, anticipatory speech anxiety was also assessed with the Spielberger State-Trait Anxiety Inventory - State version (STAI-S). Analyses included all randomized patients with outcome data at posttreatment. This study is registered at ISRCTN, number 98890605.

Findings

Between March 17th 2014 and May 22nd 2015, 47 patients were recruited. One patient in the covert group dropped out after a few days of treatment and did not provide fMRI data, leaving 46 patients with complete outcome data. After nine weeks of treatment, overt (n = 24) as compared to covert (n = 22) SSRI administration yielded significantly better outcome on the LSAS-SR (adjusted difference 21.17, 95% CI 10.69–31.65, p < 0.0001) with more than three times higher response rate (50% vs. 14%; χ²(1) = 6.91, p = 0.009) and twice the effect size (d = 2.24 vs. d = 1.13) from pre-to posttreatment. There was no significant between-group difference on anticipatory speech anxiety (STAI-S), both groups improving with treatment. No serious adverse reactions were recorded. On fMRI outcomes, there was suggestive evidence for a differential neural response to treatment between groups in the posterior cingulate, superior temporal and inferior frontal gyri (all z thresholds exceeding 3.68, p ≤ 0.001). Reduced social anxiety with treatment correlated significantly with enhanced posterior cingulate (z threshold 3.24, p = 0.0006) and attenuated amygdala (z threshold 2.70, p = 0.003) activity.

Interpretation

The clinical and neural effects of escitalopram were markedly influenced by verbal suggestions. This points to a pronounced placebo component in SSRI-treatment of SAD and favors a biopsychosocial over a biomedical explanatory model for SSRI efficacy.

Funding resources

The Swedish Research Council for Working Life and Social Research (grant 2011-1368), the Swedish Research Council (grant 421-2013-1366), Riksbankens Jubileumsfond – the Swedish Foundation for Humanities and Social Sciences (grant P13-1270:1).

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Overt surpassed covert SSRI treatment with doubled effect size and tripled response rate on the main social anxiety outcome.

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Overt vs. covert SSRI treatment yielded different neural changes in brain areas involved in emotion-cognition interactions.

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This study suggests that the presentation of a treatment may be as important as the treatment itself.

Using truthful or deceiving verbal instructions, we tested how expectancies influence SSRI efficacy in social anxiety disorder. The number of responders was more than three times higher after open administration of escitalopram 20 mg compared to covert administration of the drug presented as “active placebo” in a cover story. Correct vs. incorrect information about the SSRI also yielded different neural changes in brain areas involved in emotion-cognition interactions. The benefit of SSRI medication seems to be highly affected by psychological factors like positive expectancies traditionally associated with placebo. Our results favor a biopsychosocial over a biomedical explanatory model for SSRI efficacy.

Pharmacogenomics in the treatment of mood disorders: Strategies and Opportunities for personalized psychiatry

Personalized medicine (personalized psychiatry in a specific setting) is a new model towards individualized care, in which knowledge from genomics and other omic pillars (microbiome, epigenomes, proteome, and metabolome) will be combined with clinical data to guide efforts to new drug development and targeted prescription of the existing treatment options. In this review, we summarize pharmacogenomic studies in mood disorders that may lay the foundation towards personalized psychiatry. In addition, we have discussed the possible strategies to integrate data from omic pillars as a future path to personalized psychiatry. So far, the progress of uncovering single nucleotide polymorphisms (SNPs) underpinning treatment efficacy in mood disorders (e.g., SNPs associated with selective serotonin re-uptake inhibitors or lithium treatment response in patients with bipolar disorder and major depressive disorder) are encouraging, but not adequate. Genetic studies have pointed to a number of SNPs located at candidate genes that possibly influence response to; (a) antidepressants COMT, HTR2A, HTR1A, CNR1, SLC6A4, NPY, MAOA, IL1B, GRIK4, BDNF, GNB3, FKBP5, CYP2D6, CYP2C19, and ABCB1 and (b) mood stabilizers (lithium) 5-HTT, TPH, DRD1, FYN, INPP1, CREB1, BDNF, GSK3β, ARNTL, TIM, DPB, NR3C1, BCR, XBP1, and CACNG2. We suggest three alternative and complementary strategies to implement knowledge gained from pharmacogenomic studies. The first strategy can be to implement diagnostic, therapeutic, or prognostic genetic testing based on candidate genes or gene products. The second alternative is an integrative analysis (systems genomics approach) to combine omics data obtained from the different pillars of omics investigation, including genomics, epigenomes, proteomics, metabolomics and microbiomes. The main goal of system genomics is an identification and understanding of biological pathways, networks, and modules underlying drug-response. The third strategy aims to the development of multivariable diagnostic or prognostic algorithms (tools) combining individual's genomic information (polygenic score) with other predictors (e.g., omics pillars, neuroimaging, and clinical characteristics) to finally predict therapeutic outcomes. An integration of molecular science with that of traditional clinical practice is the way forward to drug discoveries and novel therapeutic approaches and to characterize psychiatric disorders leading to a better predictive, preventive, and personalized medicine (PPPM) in psychiatry. With future advances in the omics technology and methodological developments for data integration, the goal of PPPM in psychiatry is promising.

Severity of anxiety- but not depression- is associated with oxidative stress in Major Depressive Disorder

BACKGROUND

Oxidative stress is implicated in both depression and anxiety, but it is currently unclear whether this relates to syndromal diagnoses or trans-diagnostic dimensional symptoms. We examined the relationship between oxidative stress and severity of depression and anxiety symptoms in individuals with Major Depressive Disorder (MDD).

METHODS

Plasma oxidative stress markers F2-isoprostanes and oxidized glutathione (GSSG), and the antioxidant reduced glutathione (GSH), were assessed in 69 physically healthy, medication-free MDD subjects. Symptoms of anxiety and depression were assessed using the Hamilton Anxiety (HAM-A) and Hamilton Depression (HAM-D) Rating Scales. Total HAM-A and HAM-D scores, along with "core" anxiety and depression subscales, and individual HAM-D items "psychic anxiety" and "depressed mood," were related to oxidative stress markers. Analyses controlled for age, sex, BMI, and smoking.

RESULTS

Total HAM-A ratings were positively associated with F2-isoprostanes (β=.26, p=.042) and GSSG (β=.25, p=.049), but not GSH (β=.05, p=.711). Core anxiety severity was positively associated with F2-isoprostanes (β=.34, p=.012) and GSSG, although this did not reach significance (β=.24, p=.074). None of the biological markers were significantly associated with total HAM-D or core depression ratings (all p>.13). Subjects scoring high on "psychic anxiety" had elevated F2-isoprostanes (p=.030) and GSSG (p=.020). This was not seen with "depressed mood" scores (all p>.12).

LIMITATIONS

We assessed peripheral oxidative markers, but their relationship to the brain is unclear.

CONCLUSIONS

Oxidative stress is more closely related to anxiety than depression symptoms in MDD. This highlights the importance of relating oxidative stress to specific symptoms and could provide new insights into the biological correlates of affective disorders.

Serotonin and brain function: a tale of two receptors

Previous attempts to identify a unified theory of brain serotonin function have largely failed to achieve consensus. In this present synthesis, we integrate previous perspectives with new and older data to create a novel bipartite model centred on the view that serotonin neurotransmission enhances two distinct adaptive responses to adversity, mediated in large part by its two most prevalent and researched brain receptors: the 5-HT1A and 5-HT2A receptors. We propose that passive coping (i.e. tolerating a source of stress) is mediated by postsynaptic 5-HT1AR signalling and characterised by stress moderation. Conversely, we argue that active coping (i.e. actively addressing a source of stress) is mediated by 5-HT2AR signalling and characterised by enhanced plasticity (defined as capacity for change). We propose that 5-HT1AR-mediated stress moderation may be the brain's default response to adversity but that an improved ability to change one's situation and/or relationship to it via 5-HT2AR-mediated plasticity may also be important - and increasingly so as the level of adversity reaches a critical point. We propose that the 5-HT1AR pathway is enhanced by conventional 5-HT reuptake blocking antidepressants such as the selective serotonin reuptake inhibitors (SSRIs), whereas the 5-HT2AR pathway is enhanced by 5-HT2AR-agonist psychedelics. This bipartite model purports to explain how different drugs (SSRIs and psychedelics) that modulate the serotonergic system in different ways, can achieve complementary adaptive and potentially therapeutic outcomes.

Shortage of psychotropic medications in community pharmacies in Saudi Arabia: Causes and solutions

Background: Patients with mental disorders, such as depression and anxiety, who seek medical care in private psychiatric clinics in Riyadh, Saudi Arabia, have recently expressed concerns to doctors about difficulty in filling psychotropic medications, such as Amitriptyline and Aripiprazole, at retail community pharmacies. Objectives: The aim of this study was to investigate whether there is a shortage of some commonly prescribed psychotropic medications in retail community pharmacies in Saudi Arabia, and if so, to explore the possible reasons behind the shortage of these medications. Methods: The availability of 28 commonly prescribed psychotropic medications was checked in multiple retail community pharmacies in 4 different regions of Saudi Arabia. Further, potential reasons behind the shortage of some psychotropic medications in retail community pharmacies were also explored. Results: Amitriptyline, Amoxapine, Aripiprazole, Bupropion, Buspirone, Duloxetine, Haloperidol, Hydroxyzine, Lithium, Prochlorperazine, Procyclidine, Promethazine, Thioridazine, Trazodone, and Trifluoperazine were unavailable in over half of the 248 community pharmacies surveyed. Four possible reasons behind the shortage of these medications were reported by 31 pharmacists working in different retail community pharmacies' purchasing departments, with a majority (58.06%) reporting the primary reason for a shortage of these medications that they are slow-moving items with low profit margins. Conclusions: The findings of this study should expedite the reform process in both the Ministry of Health and the Saudi Food and Drug Authority (SFDA) to publish and enforce an essential list of medications for retail community pharmacies, which should include the most commonly prescribed psychotropic medications.

Reevaluating the Efficacy and Predictability of Antidepressant Treatments: A Symptom Clustering Approach

IMPORTANCE

Depressive severity is typically measured according to total scores on questionnaires that include a diverse range of symptoms despite convincing evidence that depression is not a unitary construct. When evaluated according to aggregate measurements, treatment efficacy is generally modest and differences in efficacy between antidepressant therapies are small.

OBJECTIVES

To determine the efficacy of antidepressant treatments on empirically defined groups of symptoms and examine the replicability of these groups.

DESIGN, SETTING, AND PARTICIPANTS

Patient-reported data on patients with depression from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial (n = 4039) were used to identify clusters of symptoms in a depressive symptom checklist. The findings were then replicated using the Combining Medications to Enhance Depression Outcomes (CO-MED) trial (n = 640). Mixed-effects regression analysis was then performed to determine whether observed symptom clusters have differential response trajectories using intent-to-treat data from both trials (n = 4706) along with 7 additional placebo and active-comparator phase 3 trials of duloxetine (n = 2515). Finally, outcomes for each cluster were estimated separately using machine-learning approaches. The study was conducted from October 28, 2014, to May 19, 2016.

MAIN OUTCOMES AND MEASURES

Twelve items from the self-reported Quick Inventory of Depressive Symptomatology (QIDS-SR) scale and 14 items from the clinician-rated Hamilton Depression (HAM-D) rating scale. Higher scores on the measures indicate greater severity of the symptoms.

RESULTS

Of the 4706 patients included in the first analysis, 1722 (36.6%) were male; mean (SD) age was 41.2 (13.3) years. Of the 2515 patients included in the second analysis, 855 (34.0%) were male; mean age was 42.65 (12.17) years. Three symptom clusters in the QIDS-SR scale were identified at baseline in STAR*D. This 3-cluster solution was replicated in CO-MED and was similar for the HAM-D scale. Antidepressants in general (8 of 9 treatments) were more effective for core emotional symptoms than for sleep or atypical symptoms. Differences in efficacy between drugs were often greater than the difference in efficacy between treatments and placebo. For example, high-dose duloxetine outperformed escitalopram in treating core emotional symptoms (effect size, 2.3 HAM-D points during 8 weeks, 95% CI, 1.6 to 3.1; P < .001), but escitalopram was not significantly different from placebo (effect size, 0.03 HAM-D points; 95% CI, -0.7 to 0.8; P = .94).

CONCLUSIONS AND RELEVANCE

Two common checklists used to measure depressive severity can produce statistically reliable clusters of symptoms. These clusters differ in their responsiveness to treatment both within and across different antidepressant medications. Selecting the best drug for a given cluster may have a bigger benefit than that gained by use of an active compound vs a placebo.

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

BACKGROUND

In current psychiatric practice, antidepressants are widely and with ever-increasing frequency prescribed to patients. However, several scientific biases obfuscate estimates of antidepressants' efficacy and harm, and these are barely recognized in treatment guidelines. The aim of this mini-review is to critically evaluate the efficacy and harm of antidepressants for acute and maintenance treatment with respect to systematic biases related to industry funding and trial methodology.

METHODS

Narrative review based on a comprehensive search of the literature.

RESULTS

It is shown that the pooled efficacy of antidepressants is weak and below the threshold of a minimally clinically important change once publication and reporting biases are considered. Moreover, the small mean difference in symptom reductions relative to placebo is possibly attributable to observer effects in unblinded assessors and patient expectancies. With respect to trial dropout rates, a hard outcome not subjected to observer bias, no difference was observed between antidepressants and placebo. The discontinuation trials on the efficacy of antidepressants in maintenance therapy are systematically flawed, because in these studies, spontaneous remitters are excluded, whereas half of all patients who remitted on antidepressants are abruptly switched to placebo. This can cause a severe withdrawal syndrome that is easily misdiagnosed as a relapse when assessed on subjective symptom rating scales. In accordance, the findings of naturalistic long-term studies suggest that maintenance therapy has no clear benefit, and non-drug users do not show increased recurrence rates. Moreover, a growing body of evidence from hundreds of randomized controlled trials suggests that antidepressants cause suicidality, but this risk is underestimated because data from industry-funded trials are systematically flawed. Unselected, population-wide observational studies indicate that depressive patients who use antidepressants are at an increased risk of suicide and that they have a higher rate of all-cause mortality than matched controls.

CONCLUSION

The strong reliance on industry-funded research results in an uncritical approval of antidepressants. Due to several flaws such as publication and reporting bias, unblinding of outcome assessors, concealment and recoding of serious adverse events, the efficacy of antidepressants is systematically overestimated, and harm is systematically underestimated. Therefore, I conclude that antidepressants are largely ineffective and potentially harmful.

Looking back (and in)to the future: A personal reflection on 'Serotonin autoreceptor function and antidepressant drug action' (Hjorth et al., 2000)

Our article in this journal some 15 years ago focussed on the role of serotonin (5-HT) autoreceptors in the mechanism of action of antidepressant drugs. Specifically in this regard, the results were summarised of rat microdialysis studies carried out to examine: (a) the relative importance of 5-HT_1A and 5-HT_1B autoreceptors, including (b) possible regional variation, and (c) potential changes in autoreceptor responsiveness following chronic selective serotonin reuptake inhibitor administration. In the present reflection piece, I recap some of the key findings against a brief background and provide an account of their bearing within the context of subsequent endeavours in the antidepressant drug research and development field. I conclude by shortly commenting on selected topics relevant to novel, interesting advances and avenues for future research.

Canadian Network for Mood and Anxiety Treatments (CANMAT) 2016 Clinical Guidelines for the Management of Adults with Major Depressive Disorder: Section 3. Pharmacological Treatments

BACKGROUND

The Canadian Network for Mood and Anxiety Treatments (CANMAT) conducted a revision of the 2009 guidelines by updating the evidence and recommendations. The scope of the 2016 guidelines remains the management of major depressive disorder (MDD) in adults, with a target audience of psychiatrists and other mental health professionals.

METHODS

Using the question-answer format, we conducted a systematic literature search focusing on systematic reviews and meta-analyses. Evidence was graded using CANMAT-defined criteria for level of evidence. Recommendations for lines of treatment were based on the quality of evidence and clinical expert consensus. "Pharmacological Treatments" is the third of six sections of the 2016 guidelines. With little new information on older medications, treatment recommendations focus on second-generation antidepressants.

RESULTS

Evidence-informed responses are given for 21 questions under 4 broad categories: 1) principles of pharmacological management, including individualized assessment of patient and medication factors for antidepressant selection, regular and frequent monitoring, and assessing clinical and functional outcomes with measurement-based care; 2) comparative aspects of antidepressant medications based on efficacy, tolerability, and safety, including summaries of newly approved drugs since 2009; 3) practical approaches to pharmacological management, including drug-drug interactions and maintenance recommendations; and 4) managing inadequate response and treatment resistance, with a focus on switching antidepressants, applying adjunctive treatments, and new and emerging agents.

CONCLUSIONS

Evidence-based pharmacological treatments are available for first-line treatment of MDD and for management of inadequate response. However, given the limitations of the evidence base, pharmacological management of MDD still depends on tailoring treatments to the patient.

Effects of anti-depressant treatments on FADD and p-FADD protein in rat brain cortex: enhanced anti-apoptotic p-FADD/FADD ratio after chronic desipramine and fluoxetine administration

RATIONALE

Fas-associated death domain (FADD) is an adaptor of death receptors that can also induce anti-apoptotic actions through its phosphorylated form (p-FADD). Activation of monoamine receptors, indirect targets of classic anti-depressant drugs (ADs), reduced FADD and increased p-FADD and p-FADD/FADD ratio in brain.

OBJECTIVES

To ascertain whether ADs, which indirectly regulate monoamine receptors, modulate FADD protein forms to promote anti-apoptotic actions.

METHODS

The effects of selected norepinephrine transporter (NET), serotonin transporter (SERT), monoamine oxidase (MAO) inhibitors, atypical ADs, and electroconvulsive shock (ECS) or behavioral procedures (forced swim test, FST) on FADD forms and pro-survival FADD-like interleukin-1β-converting enzyme-inhibitory protein (FLIP-L) and phosphoprotein enriched in astrocytes of 15 kDa (p-PEA-15) contents were assessed in rat brain cortex by western blot analysis.

RESULTS

Acute NET (e.g., nisoxetine) but not SERT (e.g., fluoxetine) inhibitors decreased cortical FADD (up to 37 %) and increased p-FADD/FADD ratio (up to 1.9-fold). Nisoxetine effects were prevented by α2-antagonist RX-821002, suggesting the involvement of presynaptic α2-autoreceptors. Immobility time in the FST correlated with increases of pro-apoptotic FADD and decreases of anti-apoptotic p-FADD. The MAO-A/B inhibitor phenelzine decreased FADD (up to 33 %) and increased p-FADD (up to 65 %) and p-FADD/FADD (up to 2.4-fold). Other MAO inhibitors (clorgyline, Ro 41-1049, rasagiline), atypical ADs (ketamine and mirtazapine), or ECS did not modulate cortical FADD. Chronic (14 days) desipramine and fluoxetine, but not phenelzine, increased p-FADD (up to 59 %), p-FADD/FADD ratio (up to 1.8-fold), and pro-survival p-PEA-15 (up to 46 %) in rat brain cortex.

CONCLUSIONS

Multifunctional FADD protein, through an increased p-FADD/FADD ratio, could participate in the mechanisms of anti-apoptotic actions induced by ADs.

A Selective Nociceptin Receptor Antagonist to Treat Depression: Evidence from Preclinical and Clinical Studies

Nociceptin/Orphanin FQ (N/OFQ) is an endogenous ligand of the N/OFQ peptide (NOP) receptor, which is a G protein-coupled receptor in brain regions associated with mood disorders. We used a novel, potent, and selective orally bioavailable antagonist, LY2940094, to test the hypothesis that blockade of NOP receptors would induce antidepressant effects. In this study we demonstrate that targeting NOP receptors with LY2940094 translates to antidepressant-like effects in rodent models and, importantly, to antidepressant efficacy in patients with major depressive disorder (MDD). The proof-of-concept study (POC) was an 8-week, double-blind, placebo-controlled trial that evaluated LY2940094 as a novel oral medication for the treatment of patients with MDD. Once daily oral dosing of LY2940094 at 40 mg for 8 weeks vs placebo provided some evidence for an antidepressant effect based on the change from baseline to week 8 in the GRID-Hamilton Depression Rating Scale-17 item total score, although the predefined POC efficacy criterion (probability of LY2940094 being better than placebo⩾88%) was not met (82.9%). LY2940094 also had an early effect on the processing of emotional stimuli at Week 1 as shown by an increased recognition of positive relative to negative facial expressions in an emotional test battery. LY2940094 was safe and well tolerated. Overall, these are the first human data providing evidence that the blockade of NOP receptor signaling represents a promising strategy for the treatment of MDD.

A mega-analysis of fixed-dose trials reveals dose-dependency and a rapid onset of action for the antidepressant effect of three selective serotonin reuptake inhibitors

The possible dose-dependency for the antidepressant effect of selective serotonin reuptake inhibitors (SSRIs) remains controversial. We believe we have conducted the first comprehensive patient-level mega-analysis exploring this issue, one incentive being to address the possibility that inclusion of low-dose arms in previous meta-analyses may have caused an underestimation of the efficacy of these drugs. All company-sponsored, acute-phase, placebo-controlled, fixed-dose trials using the Hamilton Depression Rating Scale (HDRS) and conducted to evaluate the effect of citalopram, paroxetine or sertraline in adult major depression were included (11 trials, n=2859 patients). The single-item depressed mood, which has proven a more sensitive measure to detect an antidepressant signal than the sum score of all HDRS items, was designated the primary effect parameter. Doses below or at the lower end of the usually recommended dose range (citalopram: 10-20 mg, paroxetine: 10 mg; sertraline: 50 mg) were superior to placebo but inferior to higher doses, hence confirming a dose-dependency to be at hand. In contrast, among doses above these, there was no indication of a dose-response relationship. The effect size (ES) after exclusion of suboptimal doses was of a more respectable magnitude (0.5) than that usually attributed to the antidepressant effect of the SSRIs. In conclusion, the observation that low doses are less effective than higher ones challenges the oft-cited view that the effect of the SSRIs is not dose-dependent and hence not caused by a specific, pharmacological antidepressant action. Moreover, we suggest that inclusion of suboptimal doses in previous meta-analyses has led to an underestimation of the efficacy of these drugs.