Do not blame the SSRIs: blame the Hamilton Depression Rating Scale

Rasch analysis of a patient-reported outcome measure for self-perceived health among psychiatric patients in Denmark

BACKGROUND

Patient-reported outcome measures (PROMs) are valuable and necessary tools for establishing and maintaining patient-centred healthcare. The PRO-Psychiatry initiative was primarily initiated to support the patient's voice in treatment decision-making and secondarily to monitor patient-perceived quality of care. The result of the initiative is a patient-reported instrument developed in collaboration between patients and clinicians. We aimed to validate the PROM developed for measuring self-perceived health among psychiatric patients in North Denmark Region, in terms of internal consistency, criterion validity and responsiveness.

METHOD

Patients in contact with a psychiatric hospital in the North Denmark Region from September 2018 to March 2021 were included in the study. The PROM constitutes a scale of 17 items covering various aspects of self-perceived health including well-being (7 items), lack of well-being (5 items) and social functioning (5 items), where the former domain entails the WHO-5 Well-Being Index. The potential range of the total scale score is 0-85. We applied McDonald's omega, average inter-item correlation (AIIC) and differential item functioning (DIF). In addition, we used mixed effects analyses to estimate temporal correlations. The instrument was compared with self-rated overall mental and psychiatric health.

RESULTS

The patient population consisted of 1132 unique patients and a total of 2476 responses corresponding to one response per patient pathway. McDonald's omega was found to be 0.92 (95% CI 0.92 to 0.93), while the AIIC was found to be 0.42 (95% CI 0.39 to 0.44). For DIF, the largest systematic variation resulted in a maximum difference of 2.3 points on the total score when adjusting for the latent trait and was found when comparing initial measurements with follow-up measurements. The correlation between the total score and the outcomes regarding overall physical and mental health was 0.52 (95% CI 0.48 to 0.56) and 0.74 (95% CI 0.72 to 0.76). Similar correlations were found for the corresponding changes over time.

CONCLUSION

The scale showed high consistency and little systematic variation between the comparison groups. The concurrent correlations and analyses of responsiveness coincided with the prespecified hypotheses. Overall, we deem the Danish PRO-Psychiatry instrument to possess suitable psychometric properties for measuring self-perceived health among a psychiatric population.

On the Meaning of the "P Factor" in Symmetrical Bifactor Models of Psychopathology: Recommendations for Future Research From the Bifactor-(S-1) Perspective

Symmetrical bifactor models are frequently applied to diverse symptoms of psychopathology to identify a general P factor. This factor is assumed to mark shared liability across all psychopathology dimensions and mental disorders. Despite their popularity, however, symmetrical bifactor models of P often yield anomalous results, including but not limited to nonsignificant or negative specific factor variances and nonsignificant or negative factor loadings. To date, these anomalies have often been treated as nuisances to be explained away. In this article, we demonstrate why these anomalies alter the substantive meaning of P such that it (a) does not reflect general liability to psychopathology and (b) differs in meaning across studies. We then describe an alternative modeling framework, the bifactor-(S-1) approach. This method avoids anomalous results, provides a framework for explaining unexpected findings in published symmetrical bifactor studies, and yields a well-defined general factor that can be compared across studies when researchers hypothesize what construct they consider "transdiagnostically meaningful" and measure it directly. We present an empirical example to illustrate these points and provide concrete recommendations to help researchers decide for or against specific variants of bifactor structure.

Impact of chosen cutoff on response rate differences between selective serotonin reuptake inhibitors and placebo

Response defined as a 50% reduction in the sum score of the Hamilton Depression Rating Scale (HDRS-17-sum) is often used to assess the efficacy of antidepressants. Critics have, however, argued that dichotomising ratings with a cutoff close to the median may lead to scores clustering on either side, the result being inflation of miniscule drug-placebo differences. Using pooled patient-level data sets from trials of three selective serotonin reuptake inhibitors (SSRIs) (citalopram, paroxetine and sertraline) (n = 7909), and from similar trials of duloxetine (n = 3478), we thus assessed the impact of different cutoffs on response rates. Response criteria were based on (i) HDRS-17-sum, (ii) the sum score of the HDRS-6 subscale (HDRS-6-sum) and (iii) the depressed mood item. The separation between SSRI and placebo with respect to response rates increased when HDRS-17-sum was replaced by HDRS-6-sum or depressed mood as effect parameter and was markedly dependent on SSRI dose. With the exception of extreme cutoff values, differences in response rates were largely similar regardless of where the cutoff was placed, and also not markedly changed by the exclusion of subjects close to the selected cutoff (e.g., ±10%). The observation of similar response rate differences between active drugs and placebo for different cutoffs was corroborated by the analysis of duloxetine data. In conclusion, the suggestion that using a cutoff close to the median when defining response has markedly overestimated the separation between antidepressants and placebo may be discarded.

Estimates of the minimal important difference to evaluate the clinical significance of antidepressants in the acute treatment of moderate-to-severe depression

The efficacy of antidepressants in the acute treatment of moderate-to-severe depression remains a controversial issue. The minimal important difference (MID) is relevant to judge the clinical significance of treatment effects. In this analysis paper, we discuss estimates of the MID for common depression outcome measures.For the Hamilton Depression Rating Scale 17-item Version (HDRS-17), according to both anchor-based and distribution-based approaches, MID estimates range from 3 to 8 points, and the most accurate values are likely between 3 and 5 points. For the 6-item version (HDRS-6), MID estimates range between 2 and 4 points. For both the Montgomery-Åsberg Depression Rating Scale (MADRS) and the Beck Depression Inventory II (BDI-II), MID estimates range between 3 and 9 points, with estimates of 3-6 points likely being the most accurate. Quality of life appears to be more important to patients than core depression symptoms. We thus also evaluated the Short-Form 36 (SF-36) mental component score, a popular mental-health-related quality of life measure. Its MID estimate is likely about 5 points. By contrast, the average treatment effects of antidepressants on the HDRS-17, HDRS-6, MADRS, BDI-II and SF-36 are 2 points, 1.5 points, 3 points, 2 points and 3-5 points, respectively.In conclusion, the efficacy of antidepressants in the acute treatment of moderate-to-severe depression consistently fails to exceed the lower bound of the MID estimates for common depression outcome measures. The clinical significance of antidepressants thus remains uncertain and we call for more research on quality of life measures, which are the patients' most valued outcome domains.

Antipsychotic-placebo separation on the PANSS-6 subscale as compared to the PANSS-30: a pooled participant-level analysis

In order for measurement-based care to be implemented, there is a need for brief rating instruments that can be administered in a short amount of time, but that are still sufficiently informative. Here, we assessed the drug-placebo sensitivity of the six-item subscale (PANSS-6) of the 30-item Positive and Negative Syndrome Scale (PANSS-30) using a large collection of patient-level data (n = 6685) from randomized controlled trials of risperidone and paliperidone. When analyzing the data by study, we found no material difference in mean effect sizes (ES) between the two measures (PANSS-30 ES = 0.45, PANSS-6 ES = 0.44; p = 0.642). Stratifying the pooled population according to several putative effect moderators (e.g., age, formulation, dose, or diagnosis) generally yielded no meaningful ES differences between the two measures. Similarly, early improvement (≥20% improvement at week 1) on the PANSS-6 predicted subsequent response (≥40% improvement at endpoint) as well as the analog prediction using PANSS-30. Finally, cross-sectional symptom remission assessed via the PANSS-6 showed very good agreement (sensitivity = 100%, specificity = 98%) with cross-sectional symptom remission defined by the Remission in Schizophrenia Working Group.

Do side effects of antidepressants impact efficacy estimates based on the Hamilton Depression Rating Scale? A pooled patient-level analysis

The Hamilton Depression Rating Scale (HDRS-17) measures symptoms that may overlap with common antidepressant side effects (e.g., sexual dysfunction), thus making it possible that side effects of antidepressant treatment are erroneously rated as symptoms of depression, and vice versa. This study uses patient-level data from previously conducted antidepressant treatment trials to assess whether side effect ratings co-vary with HDRS-17 ratings. Data from all HDRS-17-rated, industry-sponsored pre- and post-marketing trials (n = 4647) comparing the serotonin and noradrenaline reuptake inhibitor, duloxetine, to placebo and/or to a selective serotonin reuptake inhibitor were pooled; three studies, which utilised sub-therapeutic doses, did not have symptom-level ratings available and could not be included. Severity was assessed for side effects related to sleep, somatic anxiety, gastrointestinal function, and sexual dysfunction. Analysis of covariance was used to assess the relation between these side effects and ratings of relevant HDRS-17-derived outcome parameters. Side effects related to sleep, somatic anxiety and sexual dysfunction significantly and exclusively associated with higher scores on HDRS-17 items measuring the corresponding domains. Side effects related to gastrointestinal function associated with higher HDRS-17 item scores on all assessed domains. Treatment outcome was significantly related to side effect severity when assessed using HDRS-17-sum (beta 0.32 (0.074), p < 0.001), but not when the HDRS-6-sum-score (beta 0.035 (0.043), p = 0.415) or the depressed mood item (beta 0.007 (0.012), p = .527) were used as effect parameters. That some HDRS-17 items co-vary with common antidepressant side effects suggests some of these adverse events are counted twice, potentially leading to an underestimation of antidepressant efficacy.

One (effect) size does not fit at all: Interpreting clinical significance and effect sizes in depression treatment trials

The efficacy of antidepressants in major depressive disorder has been continually questioned, mainly on the basis of studies using the sum-score of the Hamilton Depression Rating Scale as a primary outcome parameter. On this measure antidepressants show a standardised mean difference of around 0.3, which some authors suggested is below the cut-off for clinical significance. Prompted by a recent review that, using this argument, concluded antidepressants should not be used for adults with major depressive disorder, we (a) review the evidence in support of the cut-off for clinical significance espoused in that article (a Hamilton Depression Rating Scale standardised mean difference of 0.875); (b) discuss the limitations of average Hamilton Depression Rating Scale sum-score differences between groups as measure of clinical significance; (c) explore alternative measures of clinical importance; and (d) suggest future directions to help overcome disagreements on how to define clinical significance. We conclude that (a) the proposed Hamilton Depression Rating Scale cut-off of 0.875 has no scientific basis and is likely misleading; (b) there is no agreed upon way of delineating clinically significant from clinically insignificant; (c) evidence suggests the Hamilton Depression Rating Scale sum-score underestimates antidepressant efficacy; and (d) future clinical trials should consider including measures directly reflective of functioning and wellbeing, in addition to measures focused on depression psychopathology.

Different cytokine patterns associate with melancholia severity among inpatients with major depressive disorder

BACKGROUND

Six melancholic features (MFs) of the Hamilton Depression Rating Scale (HAM-D6) represent the construct of melancholia along a continuum of severity (from least to most severe: depressed mood, work and activities, somatic symptoms, psychic anxiety, guilty feelings, psychomotor retardation). We aimed to evaluate the association between these MFs and inflammatory cytokines (IC) in the blood.

METHODS

Each IC [interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin 2 (IL-2), IL-4, IL-6, IL-10, and IL-17] was associated with the HAM-D6 MFs of 139 severely depressed inpatients, using multiple linear regressions adjusted for covariates. Levels were compared with those of 100 healthy controls.

RESULTS

Depressed mood was associated with higher levels of IL-4 (β = 0.167; p = 0.041). Psychic anxiety: lower IL-17 levels (β = -0.173; p = 0.039). Guilt feelings: lower IL-2 levels (β = -0.168; p = 0.041) Psychomotor retardation: higher IL-6 levels (β = 0.195; p = 0.017). Depressed patients' TNF-α, INF-γ, and IL-4 levels were not significantly different from controls. Depressed patients' IL-2, IL-6, IL-10, and IL-17 levels were higher than those of controls (p <0.001).

CONCLUSION

Less severe MFs (depressed mood, psychic anxiety, and guilt feelings) were associated with an anti-inflammatory pattern (higher IL-4, lower IL-17 and lower IL-2, respectively). The presence of the most severe MF, psychomotor retardation, was associated with a higher pro-inflammatory response (higher IL-6).

Electroconvulsive therapy (ECT) for moderate-severity major depression among the elderly: Data from the pride study

BACKGROUND

Electroconvulsive therapy (ECT) is usually reserved for treatment of severe major depressive disorder (MDD), but may be equally effective in the treatment of moderate-severity MDD. This possibility, however, has only been studied to a very limited extent. We therefore investigated the efficacy of ECT after stratifying patients into severe MDD and moderate-severity MDD.

METHODS

We used data from the Prolonging Remission in Depressed Elderly (PRIDE) study, in which 240 patients (≥60 years) with MDD were treated with right unilateral ultrabrief pulse ECT, combined with venlafaxine. We used the six-item core depression subscale (HAM-D₆) of the Hamilton Depression Rating Scale to define depression severity. Participants with baseline total scores ≥12 on the HAM-D₆ were considered to have severe MDD, while those with HAM-D₆ total scores <12 were considered to have moderate-severity MDD.

RESULTS

Among the participants with severe MDD and moderate-severity MDD, the mean change in the HAM-D₆ total score from baseline to endpoint was -8.2 (95% confidence interval (95%CI) = -7.5; -9.0, paired t-test: p < 0.001) and -5.9 (95%CI = -5.1; -6.6, paired t-test: p < 0.001), respectively. A total of 63% of those with severe MDD and 75% of those with moderate-severity MDD achieved remission (HAM-D₆ total score ≤4) (Pearson's 2-sample chi-squared test of difference between groups: p = 0.27).

LIMITATIONS

The PRIDE study was not designed to address this research question.

CONCLUSIONS

ECT combined with venlafaxine appears to be an effective treatment for moderate-severity MDD. It may be appropriate to expand the indications for ECT to include patients with moderate-severity MDD.

Thyroid hormone treatment in the management of treatment-resistant unipolar depression: a systematic review and meta-analysis

BACKGROUND

Treatment with thyroid hormones is occasionally used in the management of treatment-resistant depression. However, the evidence supporting this treatment is not fully established. The aim of this study was to systematically review the literature on the effect of adjunctive thyroid hormone in the management of treatment-resistant unipolar depression and to provide a pooled estimate of its efficacy.

METHODS

The study is registered with PROSPERO (reg. no. CRD42018108088) and followed the PRISMA guidelines. Searches were carried out on June 24, 2019, in PubMed, EMBASE, and PsycINFO. Each record was screened independently by at least two reviewers. In instances of discrepancies, consensus was reached upon discussion. Pooled efficacy estimates were calculated based on response rates (decrease of ≥50% on the primary outcome measure) using random effect statistics.

RESULTS

The search yielded 1355 records. Based on the screening of these records, we identified 10 studies that met the inclusion criteria (total number of patients = 663). The comparison of response to thyroid hormones vs. placebo resulted in an odds ratio of 1.56 (95% CI: 0.50-4.84). Similarly, the comparison of response to thyroid hormones vs. lithium resulted in an odds ratio of 1.91 (95% CI: 0.85-4.26). Thus, adjunctive therapy with thyroid hormones was not superior to placebo or lithium in the management of treatment-resistant unipolar depression.

CONCLUSION

According to this review and meta-analysis, there is not sufficient evidence to support the use of adjunctive thyroid hormones for treatment-resistant unipolar depression.

Efficacy of new-generation antidepressants assessed with the Montgomery-Asberg Depression Rating Scale, the gold standard clinician rating scale: A meta-analysis of randomised placebo-controlled trials

BACKGROUND

It has been claimed that efficacy estimates based on the Hamilton Depression Rating-Scale (HDRS) underestimate antidepressants true treatment effects due to the instrument's poor psychometric properties. The aim of this study is to compare efficacy estimates based on the HDRS with the gold standard procedure, the Montgomery-Asberg Depression Rating-Scale (MADRS).

METHODS AND FINDINGS

We conducted a meta-analysis based on the comprehensive dataset of acute antidepressant trials provided by Cipriani et al. We included all placebo-controlled trials that reported continuous outcomes based on either the HDRS 17-item version or the MADRS. We computed standardised mean difference effect size estimates and raw score drug-placebo differences to evaluate thresholds for clinician-rated minimal improvements (clinical significance). We selected 109 trials (n = 32,399) that assessed the HDRS-17 and 28 trials (n = 11,705) that assessed the MADRS. The summary estimate (effect size) for the HDRS-17 was 0.27 (0.23 to 0.30) compared to 0.30 (0.22 to 0.38) for the MADRS. The effect size difference between HDRS-17 and MADRS was thus only 0.03 and not statistically significant according to both subgroup analysis (p = 0.47) and meta-regression (p = 0.44). Drug-placebo raw score difference was 2.07 (1.76 to 2.37) points on the HDRS-17 (threshold for minimal improvement: 7 points according to clinician-rating and 4 points according to patient-rating) and 2.99 (2.24 to 3.74) points on the MADRS (threshold for minimal improvement: 8 points according to clinician-rating and 5 points according to patient-rating).

CONCLUSIONS

Overall there was no meaningful difference between the HDRS-17 and the MADRS. These findings suggest that previous meta-analyses that were mostly based on the HDRS did not underestimate the drugs' true treatment effect as assessed with MADRS, the preferred outcome rating scale. Moreover, the drug-placebo differences in raw scores suggest that treatment effects are indeed marginally small and with questionable importance for the average patient.

Cognitive Deficits in Older Adults With Psychotic Depression: A Meta-Analysis

A major depressive disorder with psychotic features, that is, psychotic depression (PD), is often accompanied by cognitive deficits, particularly in older patients. We aimed to assess to what extent various cognitive domains are affected in older patients with PD compared to those with nonpsychotic depression (NPD). Therefore, a systematic search was conducted in Medline, Embase, Web of Science, the Cumulative Index to Nursing and Allied Literature (CINAHL), Google Scholar, and Cochrane for all relevant studies. Hereafter, we conducted a meta-analysis of seven studies on cognitive deficits in older adults (55+ years), comparing patients with PD and patients with NPD. Compared to patients with NPD, those with PD not only showed a significantly poorer performance on overall cognitive function, with a Hedges' g effect size of -0.34 (95% confidence interval: -0.56; -0.12; p = 0.003), but also on nearly all separate cognitive domains, with Hedges' g effect sizes ranging from -0.26 to -0.64 (all p's <0.003), of which attention was most adversely affected. Verbal fluency showed no significant effect, although this analysis may have been underpowered. The funnel plot suggested no significant publication bias (Egger test intercept: -2.47; 95% confidence interval: -5.50; 0.55; p = 0.09). We conclude that older patients with PD show more cognitive deficits on all cognitive domains, except for verbal fluency, compared to patients with NPD. It is crucial that clinicians and researchers take cognitive deficits into consideration in older adults with PD.

Multiple possible inaccuracies cast doubt on a recent report suggesting selective serotonin reuptake inhibitors to be toxic and ineffective

According to a systematic review on the use of selective serotonin reuptake inhibitors (SSRIs) in adult depression that was recently published in BMC Psychiatry, the results of which have been widely disseminated in lay media, these drugs increase the risk for serious adverse events (SAEs) while exerting poor antidepressant efficacy. A cursory analysis, however, suggests the analysis of SAEs conducted by the authors to be marred by both methodological inaccuracies and blatant errors. After having corrected for these apparent mistakes, we conducted a sensitivity analysis in which we also accounted for a possible moderating effect of age; while this suggests SSRIs to be safe drugs in the non-elderly, they do confirm what is already known, that is, that they may enhance the risk for SAEs in the old. Given the loose definition of SAE, including also innocuous phenomena, the possible clinical significance of the latter observation, however, remains unclear until the nature and actual impact of the SAEs in question have been clarified. Moreover, with respect to efficacy, we find the paper in BMC Psychiatry misleading: first, the authors seem unaware of the well-established shortcomings associated with the conventional efficacy parameter on which their analysis is based, second, they have included suboptimal SSRI doses and third, they have missed some pivotal trials. Unless there are explanations for the many peculiarities in this paper that have escaped us, and which may be satisfactorily clarified by the authors, it seems important that the conclusions presented in this paper be publicly rectified.

Great boast, small roast on effects of selective serotonin reuptake inhibitors: response to a critique of our systematic review

Our systematic review in BMC Psychiatry concluded that selective serotonin reuptake inhibitors (SSRIs) compared with placebo significantly increase the risk of serious adverse events (SAEs) in patients with major depression and the potential beneficial effects of SSRIs seem to be outweighed by the harms. Hieronymus et al. accused us of methodological inaccuracies and blatant errors. In their post-hoc analysis of our data, they reported that SSRIs only increase the risk of SAEs in elderly and seems safe for non-elderly patients. They also found our review misleading because our efficacy analyses were based on the 17-item Hamilton Depression Rating Scale; we included suboptimal SSRI doses; and we missed some 'pivotal trials'. We do not agree with Hieronymus et al. regarding several of the 'errors' they claim that we have made. However, we acknowledge that they have identified minor errors and that we missed some trials. After rectifying the errors and inclusion of the missed trials by us and Hieronymus et al., we re-analysed the data. The updated analyses are even more robust and confirm our earlier conclusions. SSRIs significantly increase the risk of an SAE both in non-elderly (p=0.045) and elderly (p=0.01) patients [overall odds ratio 1.39; 95% confidence interval (CI) 1.13 to 1.73; p=0.002; I2=0%]. Moreover, SSRIs did not change noticeably the 17-item Hamilton Depression Rating Scale, the internationally accepted scale (mean difference -2.02 points; 95% CI -2.38 to -1.66; p<0.00001). We found no differential effect of dose (p=0.20).

Initial severity of major depression and efficacy of new generation antidepressants: individual participant data meta-analysis

OBJECTIVE

The role of baseline severity as effect modifier in various psychiatric disorders is a topic of controversy and of clinical import. This study aims to examine whether baseline severity modifies the efficacy of various antidepressants for major depression through individual participant data (IPD) meta-analysis.

METHOD

We identified all placebo-controlled, double-blind randomised trials of new generation antidepressants in the acute phase treatment of major depression conducted in Japan and requested their IPD through the public-private partnerships (PPPs) between the relevant academic societies and the pharmaceutical companies. The effect modification by baseline depression severity was examined through six increasingly complex competing mixed-effects models for repeated measures.

RESULTS

We identified eleven eligible trials and obtained IPD from six, which compared duloxetine, escitalopram, mirtazapine, paroxetine or bupropion against placebo (total n = 2464). The best-fitting model revealed that the interaction between baseline severity and treatment was not statistically significant (coefficient = -0.04, 95% confidence interval: -0.16 to 0.08, P = 0.49). Several sensitivity analyses confirmed the robustness of the findings.

CONCLUSION

We may expect as much benefit from antidepressant treatments for mild, moderate or severe major depression. Clinical practice guidelines will need to take these findings into consideration.