Characterization of treatment resistant depression episodes in a cohort of patients from a US commercial claims database

Assessing remission in major depressive disorder using a functional-structural data fusion pipeline: A CAN-BIND-1 study

Neural network-level changes underlying symptom remission in major depressive disorder (MDD) are often studied from a single perspective. Multimodal approaches to assess neuropsychiatric disorders are evolving, as they offer richer information about brain networks. A FATCAT-awFC pipeline was developed to integrate a computationally intense data fusion method with a toolbox, to produce a faster and more intuitive pipeline for combining functional connectivity with structural connectivity (denoted as anatomically weighted functional connectivity (awFC)). Ninety-three participants from the Canadian Biomarker Integration Network for Depression study (CAN-BIND-1) were included. Patients with MDD were treated with 8 weeks of escitalopram and adjunctive aripiprazole for another 8 weeks. Between-group connectivity (SC, FC, awFC) comparisons contrasted remitters (REM) with non-remitters (NREM) at baseline and 8 weeks. Additionally, a longitudinal study analysis was performed to compare connectivity changes across time for REM, from baseline to week-8. Association between cognitive variables and connectivity were also assessed. REM were distinguished from NREM by lower awFC within the default mode, frontoparietal, and ventral attention networks. Compared to REM at baseline, REM at week-8 revealed increased awFC within the dorsal attention network and decreased awFC within the frontoparietal network. A medium effect size was observed for most results. AwFC in the frontoparietal network was associated with neurocognitive index and cognitive flexibility for the NREM group at week-8. In conclusion, the FATCAT-awFC pipeline has the benefit of providing insight on the 'full picture' of connectivity changes for REMs and NREMs while making for an easy intuitive approach.

Repetitive Transcranial Magnetic Stimulation With and Without Text4Support for the Treatment of Resistant Depression: Protocol for a Patient-Centered Multicenter Randomized Controlled Pilot Trial

BACKGROUND

Treatment-resistant depression (TRD) is the inability of a patient with major depressive disorder (MDD) to accomplish or achieve remission after an adequate trial of antidepressant treatments. Several combinations and augmentation treatment strategies for TRD exist, including the use of repetitive transcranial magnetic stimulation (rTMS), and new therapeutic options are being introduced. Text4Support, a text message-based form of cognitive behavioral therapy that allows patients with MDD to receive daily supportive text messages for correcting or altering negative thought patterns through positive reinforcement, may be a useful augmentation treatment strategy for patients with TRD. It is however currently unknown if adding the Text4Support intervention will enhance the response of patients with TRD to rTMS treatment.

OBJECTIVE

This study aims to assess the initial comparative clinical effectiveness of rTMS with and without the Text4Support program as an innovative patient-centered intervention for the management of patients diagnosed with TRD.

METHODS

This study is a multicenter, prospective, parallel-design, 2-arm, rater-blinded randomized controlled pilot trial. The recruitment process is scheduled to last 12 months. It will involve active treatment for 6 weeks, observation, and a follow-up period of 6 months for participants in the study arms. In total, 200 participants diagnosed with TRD at rTMS care clinics in Edmonton, Alberta, and rTMS clinics in Halifax, Nova Scotia will be randomized to 1 of 2 treatment arms (rTMS sessions alone or rTMS sessions plus Text4Support intervention). Participants in each group will be made to complete evaluation measures at baseline, and 1, 3, and 6 months. The primary outcome measure will be the mean change in the scores of the Patient Health Questionnaire-9 (PHQ-9). The secondary outcome measures will involve the scores of the 7-item Generalized Anxiety Disorders Scale (GAD-7), Columbia-Suicide Severity Rating Scale (CSSRS), and World Health Organization-Five Well-Being Index (WHO-5). Patient data will be analyzed with descriptive statistics, repeated measures, and correlational analyses. Qualitative data will be analyzed using the thematic analysis framework.

RESULTS

The results of the study are expected to be available 18 months from the start of recruitment. We hypothesize that participants enrolled in the rTMS plus Text4Support intervention treatment arm of the study will achieve superior outcomes compared with the outcomes of participants enrolled in the rTMS alone arm.

CONCLUSIONS

The application of the combination of rTMS and Text4Support has not been investigated previously. Therefore, we hope that this study will provide a concrete base of data to evaluate the practical application and efficacy of using the novel combination of these 2 treatment modalities.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

PRR1-10.2196/46830.

Treatment-Resistant Depression in America Latina study: one-year follow-up of treatment resistant depression patients under standard of care reveals insights on quality of life, disability, work impairment, and depressive symptoms

Introduction

Depressive Disorders are on the rise worldwide. This is also the case in Latin America (LatAm). Treatment-Resistant Depressive Disorder (TRD) poses additional burden to patients with depression. Impacts quality of life (QoL) and other dimensions, and standard of care (SOC) is insufficient to achieve the desired clinical outcomes. Evidence from LatAm is, however, lacking. The present study was devised as a 1-year follow-up of the SOC in TRD patients in LatAm to explore the burden of TRD.

Methods

This was an observational, multinational, longitudinal study. Patients with clinical diagnosis of TRD in LatAm were included in a 1-year follow-up with SOC. Beyond the Sociodemographic characterization, outcome measures were QoL (EQ-5D-5L), disability (Sheehan Disability Scale - SDS), work productivity (Work Productivity and Activity Incapacity Questionnaire: depression - WPAI:D) and depression severity (Patient Health Questionnaire-PHQ9). Patients were assessed every 3-months and comparison was performed based on change from baseline to each visit and end of study (EOS - 12 months).

Results

Patients averaged 48 (± 13.12) years, mostly female (80.9%) and married/consensual union (42.5%) or single patients (34.4%). Despite the SOC treatment, three-quarters of the patients remained symptomatic at EOS, regardless of the significant longitudinal decrease (p ≤ 0.001). Similar trends were found for disability (p ≤ 0.001) -82.2% of the patients reporting work/school disruption at EOS-, percentage of work (34%) and activity impairment (40%) at EOS (p ≤ 0.001) and only 29.2% of patients with depressive severity "none" at EOS (p ≤ 0.001). The results portray the need to improve clinical outcomes in this complex and burdensome disease in LatAm.

Discussion

Here we show that the burden of TRD remains significant in essential dimensions of everyday life at EOS underlining the need for better therapeutic solutions. The improvements in most patients do not provide the desired outcome of return to the state before the condition. Further research should focus on identifying which treatments provide better outcomes in a real-world context.

The clinical & economic burden of treatment-resistant depression in the Gulf-Cooperation Council: The Kingdom of Saudi Arabia, Kuwait and the United Arab Emirates

OBJECTIVE

The current analysis assessed the economic and clinical burden of treatment-Resistant Depression (TRD) imposed on the Kingdom of Saudi Arabia (KSA), Kuwait and United Arab Emirates (UAE) from the societal perspective.

METHODS

A Microsoft Excel® based Markov model was developed to estimate the overall burden of disease imposed by TRD across KSA, Kuwait and UAE. Data for the models' adaptation were retrieved from literature and validated by country-specific key opinion leaders. The cycle length and time horizon used in the model were 4 weeks and 1 year, respectively.

RESULTS

The study results estimated that at the end of 1-year time horizon, overall burden imposed by TRD was 3994, 982 and 670 million USD in KSA, Kuwait, and UAE, respectively. This can be attributed to the high cost incurred due to non-responsive health state (ranging from 44% to 47%). The productivity loss was either the greatest or second greatest component of TRD's burden in the countries of interest (ranging from 32% to 43%).

CONCLUSIONS

TRD represents a large clinical and economic burden on both individual patients and society. Hence, noval and innovative treatments are especially required for the management of TRD patients.

Exome-wide association study of treatment-resistant depression suggests novel treatment targets

Treatment-resistant depression (TRD) is a severe form of major depressive disorder (MDD) with substantial public health impact and poor treatment outcome. Treatment outcome in MDD is significantly heritable, but genome-wide association studies have failed to identify replicable common marker alleles, suggesting a potential role for uncommon variants. Here we investigated the hypothesis that uncommon, putatively functional genetic variants are associated with TRD. Whole-exome sequencing data was obtained from 182 TRD cases and 2021 psychiatrically healthy controls. After quality control, the remaining 149 TRD cases and 1976 controls were analyzed with tests designed to detect excess burdens of uncommon variants. At the gene level, 5 genes, ZNF248, PRKRA, PYHIN1, SLC7A8, and STK19 each carried exome-wide significant excess burdens of variants in TRD cases (q < 0.05). Analysis of 41 pre-selected gene sets suggested an excess of uncommon, functional variants among genes involved in lithium response. Among the genes identified in previous TRD studies, ZDHHC3 was also significant in this sample after multiple test correction. ZNF248 and STK19 are involved in transcriptional regulation, PHYIN1 and PRKRA are involved in immune response, SLC7A8 is associated with thyroid hormone transporter activity, and ZDHHC3 regulates synaptic clustering of GABA and glutamate receptors. These results implicate uncommon, functional alleles in TRD and suggest promising novel targets for future research.

Suicide-specific mortality among patients with treatment-resistant major depressive disorder, major depressive disorder with prior suicidal ideation or suicide attempts, or major depressive disorder alone

BACKGROUND

The impact of treatment-resistant depression (TRD) or prior suicidal ideation/suicide attempt (SI/SA) on mortality by suicide among patients with major depressive disorder (MDD) is not well known. This retrospective, observational, descriptive cohort study characterized real-world rates of suicide-specific mortality among patients with MDD with or without TRD or SI/SA.

METHODS

Adult patients with MDD among commercially insured and Medicare enrollees in Optum Research Database were included and assigned to three cohorts: those with treatment-resistant MDD (TRD), those with MDD and SI/SA (MDD+SI/SA), and those with MDD without TRD or SI/SA (MDD alone). Suicide-specific mortality was obtained from the National Death Index. The effects of demographic characteristics and SI/SA in the year prior to the end of observation on suicide-specific mortality were assessed.

RESULTS

For the 139,753 TRD, 85,602 MDD+SI/SA, and 572,098 MDD alone cohort patients, mean age ranged from 55 to 59 years and the majority were female. At baseline, anxiety disorders were present in 53.92%, 44.11%, and 21.72% of patients with TRD, MDD+SI/SA, and MDD alone, respectively. Suicide-mortality rates in the three cohorts were 0.14/100 person-years for TRD, 0.27/100 person-years for MDD+SI/SA, and 0.04/100 person-years for MDD alone. SI/SA during the year prior to the end of observation, younger age, and male sex were associated with increased suicide risk.

CONCLUSIONS

Patients with TRD and MDD+SI/SA have a heightened risk of mortality by suicide compared with patients with MDD alone. Suicide rates were higher in patients with recent history versus older or no history of SI/SA, men versus women, and those of young age versus older age.

Therapeutic and Safety Outcomes of Intravenous Ketamine for Treatment-refractory Depression in a Veteran Population: A Case Series

INTRODUCTION

Major depressive disorder is a serious, recurrent, and disabling psychiatric illness. Despite many proven treatments with multiple medications or therapies, approximately 30% of patients fail to achieve remission and are considered to have treatment-refractory depression (TRD). Recently, there has been a growing interest in the use of intravenous (IV) ketamine for the treatment of TRD. There is limited yet increasing evidence to support the use of ketamine, a glutamate receptor antagonist, in the management of depression; however, the lack of data regarding the safety and tolerability of therapy has limited its clinical use. By analyzing a cohort of veterans with TRD and comorbid psychiatric conditions treated with IV ketamine infusions for a 24-month study period, we aim to provide critical information about ketamine's clinical effectiveness and safety.

MATERIALS AND METHODS

Based on a retrospective chart review, we identified eight veterans with TRD receiving treatment with repeated-dose IV ketamine from 2018 to 2020. The magnitude of clinical response was based on the Beck Depression Inventory self-report scale and the Patient Health Questionnaire-9, both measured at the initial patient consultation and before the beginning of each ketamine infusion treatment. Safety analysis included changes to pre- and post-ketamine infusion on vital signs, effects on alertness and sedation, and potential psychosis-like effects. For all outcomes, we estimated a linear mixed-effects model that allowed heterogeneous residual variances for each veteran. The effect of continuous predictor variables was estimated using restricted cubic splines with knot points specified at the 5th, 35th, 65th, and 95th percentiles. All the analyses were conducted using SAS v.9.4, with P < .05 indicating the statistical significance. This study had institutional review board approval: 1220.

RESULTS

During the study period, the median number of ketamine infusions was 15 across a median of 164 days of treatment follow-up with a median time between ketamine infusions of 4 days. For both Beck Depression Inventory and Patient Health Questionnaire-9 scores, there was a statistically significant reduction across infusions (both P < .001), but the strongest reduction occurred before day 40. The change was statistically significant for decreased heart rate (P = .019) but not for systolic blood pressure (P = .612), diastolic blood pressure (P = .942), respiratory rate (P = .822), oxygen saturation (P = .070), and temperature (P = .943). Side effects were reported in six patients (75%); however, the only side effect reported was excessive sedation or dizziness immediately after infusion.

CONCLUSIONS

In this study, repeated-dose IV ketamine infusions over a 24-month study period resulted in a significant reduction in depression scores in a group of veterans with TRD. The rapid onset of significant response, absence of psychosis-like effects or dissociative symptoms despite psychiatric comorbidities, and minimal effects on vital signs support the clinical efficacy and safety of this exciting new treatment option for patients with TRD. Limitations include a 2-year study period, lack of information on long-term effects, and the retrospective nature of the study. Prospective studies of longer duration are needed to assess the long-term efficacy and safety of IV ketamine for TRD.

Economic impact of reducing treatment gaps in depression

BACKGROUND

Major depressive disorder (MDD) is highly prevalent across Europe. While evidence-based treatments exist, many people with MDD have their condition undetected and/or untreated. This study aimed to assess the cost-effectiveness of reducing treatment gaps using a modeling approach.

METHODS

A decision-tree model covering a 27-month time horizon was used. This followed a care pathway where MDD could be detected or not, and where different forms of treatment could be provided. Expected costs pertaining to Germany, Hungary, Italy, Portugal, Sweden, and the UK were calculated and quality-adjusted life years (QALYs) were estimated. The incremental costs per QALY of reducing detection and treatment gaps were estimated.

RESULTS

The expected costs with a detection gap of 69% and treatment gap of 50% were €1236 in Germany, €476 in Hungary, €1413 in Italy, €938 in Portugal, €2093 in Sweden, and €1496 in the UK. The incremental costs per QALY of reducing the detection gap to 50% ranged from €2429 in Hungary to €10,686 in Sweden. The figures for reducing the treatment gap to 25% ranged from €3146 in Hungary to €13,843 in Sweden.

CONCLUSIONS

Reducing detection and treatment gaps, and maintaining current patterns of care, is likely to increase healthcare costs in the short term. However, outcomes are improved, and reducing these gaps to 50 and 25%, respectively, appears to be a cost-effective use of resources.

Pharmacotherapy for Treatment-Resistant Depression: Antidepressants and Atypical Antipsychotics

Treatment-resistant depression (TRD) affects one in three patients with major depressive disorder and is associated with increased risk of all-cause mortality. Studies of real-world practices suggest that antidepressant monotherapy continues to be the most widely used treatment after inadequate response to a first-line treatment. However, rates of remission with antidepressants in TRD are suboptimal. Atypical antipsychotics are the most widely studied augmentation agent and aripiprazole, brexpiprazole, cariprazine, quetiapine extended-release, and olanzapine-fluoxetine combination are approved for depression. Benefits of using atypical antipsychotics for TRD has to be weighted against their potential adverse events, such as weight gain, akathisia, and tardive dyskinesia.

Single-dose psilocybin for a treatment-resistant episode of major depression: Impact on patient-reported depression severity, anxiety, function, and quality of life

BACKGROUND

COMP360 is a proprietary, synthetic formulation of psilocybin being developed for treatment-resistant depression (TRD), a burdensome, life-threatening illness with high global impact. Here, we expand upon the previous report of primary outcomes from a phase 2 study of COMP360 in individuals with TRD-the largest randomised controlled clinical trial of psilocybin-to discuss findings of the exploratory efficacy endpoints.

METHODS

In this phase 2, double-blind trial, 233 participants with TRD were randomised to receive a single dose of psilocybin 25 mg, 10 mg, or 1 mg (control), administered alongside psychological support from trained therapists. Efficacy measures assessed patient-reported depression severity, anxiety, positive and negative affect, functioning and associated disability, quality of life, and cognitive function.

RESULTS

At Week 3, psilocybin 25 mg, compared with 1 mg, was associated with greater improvements from Baseline total scores in all measures. The 10 mg dose produced smaller effects across these measures.

LIMITATIONS

Interpretation of this trial is limited by the absence of an active comparator and the possibility of functional unblinding in participants who received a low dose of psilocybin.

CONCLUSIONS

Three weeks after dosing, psilocybin 25 mg and, to a lesser degree, 10 mg improved measures of patient-reported depression severity, anxiety, affect, and functioning. These results extend the primary findings from the largest randomised clinical trial of psilocybin for TRD to examine other outcomes that are of importance to patients.

Depression and suicidality severity among TRD patients after 1-year under standard of care: Findings from the TRAL study, a multicenter, multinational, observational study in Latin America

INTRODUCTION

Treatment resistant depression (TRD) is one of the most pressing issues in mental healthcare in LatAm. However, clinical data and outcomes of standard of care (SOC) are scarce. The present study reported on the Treatment-Resistant Depression in America Latina (TRAL) project 1-year follow-up of patients under SOC assessing clinical presentation and outcomes.

MATERIALS AND METHODS

420 patients with clinical diagnoses of TRD from Argentina, Brazil, Colombia and Mexico were included in a 1-year follow-up to assess clinical outcomes of depression (MADRS) and suicidality (C-SSRS), as well as evolution of clinical symptoms of depression. Patients were assessed every 3 months and longitudinal comparison was performed based on change from baseline to each visit and end of study (12 months). Socio demographic characterization was also performed.

RESULTS

Most patients were female (80.9%), married (42.5%) or single (34.4%), with at least 10 years of formal education (71%). MDD diagnosis was set at 37.29 (SD=14.00) years, and MDD duration was 11.11 years (SD=10.34). After 1-year of SOC, 79.1% of the patients were still symptomatic, and 40% of the patients displayed moderate/severe depression. Only 44.1% of the patients achieved a response (≥50% improvement in MADRS), and 60% of the sample failed to achieve remission. Suicidal ideation was reported by more than half of the patients at the end of study.

CONCLUSIONS

Depression and suicidality symptoms after a 1-year of SOC is of great concern. Better therapeutic options are needed to tackle this debilitating and burdensome disease.

The impact of early remission on disease trajectory and patient outcomes in major depression disorder (MDD): A targeted literature review and microsimulation modeling approach based on the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study

BACKGROUND

While literature has suggested that the duration of a major depressive episode (MDE) may affect both symptomatic and functional outcomes in major depressive disorder (MDD), study designs are limited in their ability to isolate a causal relationship.

METHODS

A targeted literature review was conducted using the MEDLINE database to assess whether there was an association between (1) shorter duration of an MDE, or (2) increased rapidity of symptom improvement, and MDD outcomes in adult patients. Given findings from the literature, we hypothesized that rapid symptom improvement could be associated with other longer-term clinical outcomes and used a previously-developed microsimulation model to test this hypothesis. The base case of the model replicated step-therapy treatment patterns, for 10,000 simulated patients, based on lines of therapy related to standard of care, observed remission rates, and observed time to relapse from the STAR*D study. In alternative scenario analyses, the step 1 remission rate was varied by +25 % and +50 % from the base case value to simulate the potential impact of improved earlier remission on disease trajectory and patient-level clinical outcomes.

RESULTS

The literature review (N = 35 studies) suggests a statistically significant relationship between the duration of MDE or early symptom improvement and MDD outcomes. The microsimulation model corroborated these findings and demonstrated that increasing the rate of remission in step 1 results in patients experiencing decreased number of treatment steps, faster time to remission, decreased rate of reaching treatment-resistant depression, and delayed time to relapse.

LIMITATIONS

Rates of relapse in STAR*D were deemed unreliable due to the high-loss of follow-up; rates of relapse for the MDD DTM were instead derived using parametric extrapolation methods (i.e., exponential, Weibull, log-logistic, Gaussian, log-normal, logistic). Adherence to treatment was assumed to be 100 %; however, non-adherence is expected to result in lower cumulative remission rates.

CONCLUSION

Findings from the literature, coupled with quantification through a novel microsimulation model, demonstrate the potential impact of increased remission on disease trajectory and patient outcomes in MDD. While additional analyses with the model may be warranted to explore the impact of novel interventions on population health, including long-term outcomes (i.e., 5-year follow-up, lifetime follow-up), efforts by clinicians to increase remission early in the disease trajectory may improve long-term outcomes.

Incidence of treatment-resistant depression during the first mood depressive episode

INTRODUCTION

In spite of several approaches and therapeutic measures, treatment-resistant depression (TRD) continues to inflict serious, individual and collective consequences. Therefore, there is a persistent need to scrutinize the concept of TRD in order to adapt the therapeutic strategies.

AIM

To estimate the incidence of TRD in patients with a first major depressive episode (MDD), and study factors associated with resistance.

METHODS

A descriptive prospective longitudinal study of outpatients with a first MDD, was conducted. Patients with a history of subthreshold hypomania were excluded. Eligible patients were put on a selective serotonin reuptake inhibitor (SSRI), either fluoxetine or sertraline. Participants were followed regularly until they had a therapeutic response or they met the criteria for TRD.

RESULTS

The study involved 82 adults. The incidence of treatment-resistant depression was 19.4% CI95%=[5.5-33.3]. Among the sociodemographic and clinical factors, family history of psychosis (p=0.038) and chronic respiratory comorbidities (p=0.016) were associated with TRD. The small size of the sample is a potential limitation of this study. Besides, the use of only two SSRIs could influence the results.

CONCLUSION

In this study, the incidence of TRD was at the lower limit of the rates reported in clinical studies. Clinical factors associated with TRD suggest the relevance of genotype analysis to identify patients with TRD. Furthermore, our results highlight the importance of heeding comorbidities to optimize care. Larger multicenter studies are needed to generalize.

Pharmacotherapies for Treatment-Resistant Depression: How Antipsychotics Fit in the Rapidly Evolving Therapeutic Landscape

One in three adults with major depressive disorder (MDD) do not experience clinically significant improvement after multiple sequential courses of antidepressants and have treatment-resistant depression (TRD). The presence of TRD contributes to the morbidity and excess mortality associated with MDD and has been linked to significantly increased health care expenses. In the absence of a consensus definition of TRD, this report takes a broad approach by considering inadequate response to one or more courses of antidepressants and focuses on atypical antipsychotics that are approved by the U.S. Food and Drug Administration for treatment of depression (aripiprazole, brexpiprazole, cariprazine, extended-release quetiapine, and olanzapine-fluoxetine combination). While multiple acute-phase studies have demonstrated the efficacy of these medications in improving depressive symptoms, clinically meaningful improvement (i.e., remission) remains limited, with significant concerns about side effects (including weight gain, metabolic dysfunction, extrapyramidal symptoms, and tardive dyskinesia), especially with long-term use. With the rapidly evolving landscape of antidepressant treatments over the past few years, which has witnessed approval of rapid-acting antidepressants (e.g., esketamine nasal spray and dextromethorphan-bupropion combination) and several more in the late-stage pipeline (e.g., zuranolone and psilocybin), it remains to be seen whether the use of atypical antipsychotics will go the way of the older and rarely prescribed antidepressants (such as tricyclics and monoamine oxidase inhibitors). Pragmatic clinical trials are needed to compare the effectiveness of atypical antipsychotics with TRD-specific pharmacotherapies and neuromodulation treatments and to identify the optimal sequencing of these varied approaches for patients with MDD. When using atypical antipsychotics, clinicians and patients are encouraged to use a shared decision-making approach by personalizing treatment selection based on anticipated side effects, tolerability, cost, and feasibility.

Comorbidity and healthcare utilization in patients with treatment resistant depression: A large-scale retrospective cohort analysis using electronic health records

BACKGROUND

Medical comorbidity and healthcare utilization in patients with treatment resistant depression (TRD) is usually reported in convenience samples, making estimates unreliable. There is only limited large-scale clinical research on comorbidities and healthcare utilization in TRD patients.

METHODS

Electronic Health Record data from over 3.3 million patients from the INSIGHT Clinical Research Network in New York City was used to define TRD as initiation of a third antidepressant regimen in a 12-month period among patients diagnosed with major depressive disorder (MDD). Age and sex matched TRD and non-TRD MDD patients were compared for anxiety disorder, 27 comorbid medical conditions, and healthcare utilization.

RESULTS

Out of 30,218 individuals diagnosed with MDD, 15.2 % of patients met the criteria for TRD (n = 4605). Compared to MDD patients without TRD, the TRD patients had higher rates of anxiety disorder and physical comorbidities. They also had higher odds of ischemic heart disease (OR = 1.38), stroke/transient ischemic attack (OR = 1.57), chronic kidney diseases (OR = 1.53), arthritis (OR = 1.52), hip/pelvic fractures (OR = 2.14), and cancers (OR = 1.41). As compared to non-TRD MDD, TRD patients had higher rates of emergency room visits, and inpatient stays. In relation to patients without MDD, both TRD and non-TRD MDD patients had significantly higher levels of anxiety disorder and physical comorbidities.

LIMITATIONS

The INSIGHT-CRN data lack information on depression severity and medication adherence.

CONCLUSIONS

TRD patients compared to non-TRD MDD patients have a substantially higher prevalence of various psychiatric and medical comorbidities and higher health care utilization. These findings highlight the challenges of developing interventions and care coordination strategies to meet the complex clinical needs of TRD patients.

Abnormal Prefrontal Brain Activation During a Verbal Fluency Task in Treatment-Resistant Depression Using Near-Infrared Spectroscopy

OBJECTIVE

The study investigated cognitive performance and brain function between treatment-resistant depression (TRD) and non- TRD patients to find potential neurobiological markers associated with refractoriness in depression patients.

METHODS

Fourteen TRD patients, 26 non-TRD patients and 23 healthy controls (HC) were included in the present study. The neural function of prefrontal cortex (PFC) and cognitive performance among the three group were examined using near-infrared spectroscopy (NIRS) during verbal fluency task (VFT).

RESULTS

Both TRD and non-TRD groups exhibited significantly worse VFT performance and lower activation of oxygenated hemoglobin (oxy-Hb) changes in the bilateral dorsolateral PFC (DLPFC) compared to the HC group. Within the TRD and non-TRD groups, VFT performance was no significant difference, but activation of oxy-Hb changes in dorsomedial PFC (DMPFC) in TRD patients was significantly lower than non-TRD patients. In addition, activation of oxy-Hb changes in right DLPFC were negatively correlated with the severity of depressive symptoms in depression patients.

CONCLUSION

Both TRD patients and non-TRD patients exhibited lower oxy-Hb activation in DLPFC. TRD patients exhibit lower oxy- Hb activation in DMPFC than non-TRD patients. fNIRS maybe a useful tool for predict depressive patients with or without treatment resistant.

Association of Treatment-Resistant Depression With Patient Outcomes and Health Care Resource Utilization in a Population-Wide Study

Importance

The totality of the societal and individual impact of treatment-resistant depression (TRD) is unknown, as is the potential to prognosticate TRD. The generalizability of many observational studies on TRD is limited.

Objective

To estimate the burden of TRD in a large population-wide cohort in an area with universal health care by including data from both health care types (psychiatric and nonpsychiatric) and, further, to develop a prognostic model for clinical use.

Design, Setting, and Participants

This cohort study, a population-based observational study, assessed data from the Stockholm MDD Cohort for episodes of major depressive disorder (MDD) between 2010 and 2017 that fulfilled predefined criteria for TRD (≥3 consecutive antidepressant treatments). Data analysis was performed from August 2020 to May 2022.

Main Outcomes and Measures

Outcomes were psychiatric and nonpsychiatric comorbid conditions, antidepressant treatments, health care resource utilization, lost workdays, all-cause mortality, and intentional self-harm and, in the prognostic model, TRD.

Results

A total of 158 169 unipolar MDD episodes (in 145 577 patients) were identified between January 1, 2012, and December 31, 2017 (64.7% women; median [IQR] age, 42 years [30-56]). Of these, 12 793 episodes (11%) fulfilled criteria for TRD. The median (IQR) time from the start of MDD episode to TRD was 552 days (294-932). Selective serotonin reuptake inhibitor was the most common class of antidepressant treatment in all treatment steps, and 5907 patients (46.2%) received psychotherapy at some point before initiation of the third pharmacological antidepressant treatment. Compared with matched non-TRD episodes, TRD episodes had more inpatient bed-days (mean, 3.9 days; 95% CI, 3.6-4.1, vs 1.3 days; 95% CI, 1.2-1.4) and more lost workdays (mean, 132.3 days; 95% CI, 129.5-135.1, vs 58.7 days; 95% CI, 56.8-60.6) 12 months after the index date. Anxiety, stress, sleep disorder, and substance use disorder were all more common comorbid conditions in TRD episodes. Intentional self-harm was more than 4 times more common in TRD episodes. The all-cause mortality rate for patients with MDD with TRD episodes was 10.7/1000 person-years at risk, compared with 8.7/1000 person-years at risk for patients with MDD without TRD episodes (hazard ratio, 1.23; 95% CI, 1.07-1.41). Median time from start of the first antidepressant treatment to start of the second, and from start of the second antidepressant treatment to start of the third, was 165 and 197 days, respectively. The severity of MDD, defined using the self-rating Montgomery-Åsberg Depression Rating Scale (MADRS-S) at time of MDD diagnosis, was found to be the most important prognostic factor for TRD (C index = 0.69).

Conclusions and Relevance

In this cohort study, TRD was a common variant of MDD when including patients from both health care types, which is associated with a high disease burden for both patients and society. The median time between initiation of new antidepressant treatments was longer than recommended in current treatment guidelines, suggesting room for more structured and timely depression care.

Distinct patterns of functional brain network integration between treatment-resistant depression and non treatment-resistant depression: A resting-state functional magnetic resonance imaging study

BACKGROUND

Previous neuroimaging has paid little attention to the differences in brain network integration between patients with treatment-resistant depression(TRD) and non-TRD (nTRD), and the relationship between their impaired brain network integration and clinical symptoms has not been elucidated.

METHOD

Eighty one major depressive disorder (MDD) patients (40 in TRD, 41 in nTRD) and 40 healthy controls (HCs) were enrolled for the functional magnetic resonance imaging (fMRI) scans. A seed-based functional connectivity (FC) method was used to investigate the brain network abnormalities of default mode network (DMN), affective network (AN), salience network (SN) and cognitive control network (CCN) for the MDD. Finally, the correlation was analyzed between the abnormal FCs and 17-item Hamilton Rating Scale for Depression scale (HAMD-17) scores.

RESULTS

Compared with the HC group, the FCs in DMN, AN, SN, CCN were altered in both the TRD and nTRD groups. Compared with the nTRD group, FC alterations in the AN and CCN were more abnormal in the TRD group, and the FC alterations were generally decreased at the SN in the TRD group. In addition, the FC values of right dorsolateral prefrontal cortices and left caudate nucleus in the TRD group and the FC values of right subgenual anterior cingulate cortex and left middle temporal gyrus in the nTRD group were positively correlated with HAMD-17 scale scores.

CONCLUSIONS

Abnormal FCs are present in four brain networks (DMN, AN, SN, CCN) in both the TRD and nTRD groups. Except of DMN, FCs in AN, SN and CCN maybe underlay the neurobiological mechanism in differentiating TRD from nTRD.

Comparison on the clinical features in patients with or without treatment-resistant depression: A National Survey on Symptomatology of Depression report

Patients with treatment-resistant depression (TRD) have fewer treatment options and worse prognoses than those without TRD. Although the etiology or pathophysiology of TRD remains unclear, certain clinical variables have been found to be related to its severity and prognosis. Therefore, 1151 patients with recurrent depression were recruited from the National Survey on Symptomatology of Depression (NSSD) and their depressive symptoms were assessed by using the doctor-rating assessment questionnaire. Then, the differences between patients with or without TRD were compared by parametric or nonparametric tests and the risk factors for TRD were explored by logistic regression. The results showed there were differences in clinical variables between patients with and without TRD. Additionally, we found depression with more somatic symptoms had a higher risk for TRD. Further analysis by stepwise logistic regression showed that age, gender, religious belief, drinking habit, the total course of depression, the number of hospitalizations, characteristics of seasonal episode remission, depressed mood, hypersexuality, emotionally incoherent psychotic symptoms, psychomotor agitation, respiratory system symptoms and history of suicide attempts were strongly associated with TRD. So, it is crucial for clinicians to identify these clinical features and adjust treatments timely.

Observational study to characterize treatment-resistant depression in Germany, France and the United Kingdom: analysis of real-world data collected through a survey of healthcare professionals

OBJECTIVE

This study describes treatment patterns, productivity, healthcare resource utilization and previous episodes of depression for patients with treatment-resistant depression (TRD).

METHODS

In this cross-sectional study, a quantitative survey was administered to 225 healthcare providers (HCPs) distributed evenly across Germany, France and the UK from July to August 2021. Each HCP was asked to answer based on medical records of five patients with TRD, defined as patients failing to respond to two or more treatments of adequate dose and duration in the same episode of major depressive disorder (MDD), which provided a sample size of 1125 patients.

RESULTS

Of the 1125 patients with TRD, 73.2% had two or more previous episodes of MDD, 46.3% had a history of suicidal ideation and 24.8% had attempted suicide. Only 26.8% of patients were employed either full-time or part-time. During the most recent/current TRD episode, 45.5% of patients received five or more lines of treatment, and 46.0% remained on monotherapy. For multiple pharmacological treatments, too many distinct combinations were used to discern trends. Overall, 60.6% of patients had at least one mental health-related hospitalization in the last 12 months; 35.0% had two or more hospitalizations. Half of TRD patients saw a doctor five or more times per year for their depression.

CONCLUSIONS

This study addresses the knowledge gap about treatment patterns and healthcare utilization in real-world practice for TRD patients in three European countries. It provides data that potentially could inform treatment guideline development and optimize patient-perceived benefits from the treatment of TRD.

Healthcare resource utilization in patients with treatment-resistant depression—A Danish national registry study

Objectives

To investigate healthcare resource utilization (HRU) and associated costs by depression severity and year of diagnosis among patients with treatment-resistant depression (TRD) in Denmark.

Methods

Including all adult patients with a first-time hospital contact for major depressive disorder (MDD) in 1996–2015, TRD patients were defined at the second shift in depression treatment (antidepressant medicine or electroconvulsive therapy) and matched 1:2 with non-TRD patients. The risk of utilization and amount of HRU and associated costs including medicine expenses 12 months after the TRD-defining date were reported, comparing TRD patients with non-TRD MDD patients.

Results

Identifying 25,321 TRD-patients matched with 50,638 non-TRD patients, the risk of psychiatric hospitalization following TRD diagnosis was 138.4% (95%-confidence interval: 128.3–149.0) higher for TRD patients than for non-TRD MDD patients. The number of hospital bed days and emergency department (ED) visits were also higher among TRD patients, with no significant difference for somatic HRU. Among patients who incurred healthcare costs, the associated HRU costs for TRD patients were 101.9% (97.5–106.4) higher overall, and 55.2% (50.9–59.6) higher for psychiatric services than those of non-TRD patients. The relative differences in costs for TRD-patients vs non-TRD patients were greater for patients with mild depression and tended to increase over the study period (1996–2015), particularly for acute hospitalizations and ED visits.

Limitations

TRD was defined by prescription patterns besides ECT treatments.

Conclusion

TRD was associated with increased psychiatric-related HRU. Particularly the difference in acute hospitalizations and ED visits between TRD and non-TRD patients increased over the study period.

Benefits of group compassion-focused therapy for treatment-resistant depression: A pilot randomized controlled trial

Major depression is one of the most common mental health problems worldwide. More than one-third of patients suffer from treatment-resistant depression (TRD). In this study, we explored the feasibility of group compassion-focused therapy (CFT) for TRD using a randomized controlled trial with two parallel groups. Eighteen participants were randomly allocated to the intervention group (CFT and usual care) and control group (usual care alone) and a participant in each group withdrew. Participants in the intervention group received a 1.5-h session every week for 12 weeks. The effects of the intervention on the participants' scores were calculated using a linear mixed model. There was a larger reduction in their depressive symptoms and fears of compassion for self and a greater increase in their compassion for self compared to the control group participants. The reliable clinical indices showed that in the CFT (intervention) group, three of nine participants recovered (33%), two improved (22%), two recovered but non-reliably (22%), and the condition of two remained unchanged (22%). These findings indicate adequate feasibility of group CFT for TRD in Japanese clinical settings.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [UMIN 000028698].

Treatment-resistant depression and major depression with suicide risk-The cost of illness and burden of disease

Introduction

Treatment-Resistant Depression (TRD) and Major Depression with Suicide Risk (MDSR) are types of depression with relevant effects on the health of the population and a potentially significant economic impact. This study estimates the burden of disease and the costs of illness attributed to Treatment-Resistant Depression and Major Depression with Suicide Risk in Portugal.

Methods

The disease burden for adults was quantified in 2017 using the Disability-Adjusted Life Years (DALYs) lost. Direct costs related to the health care system and indirect costs were estimated for 2017, with indirect costs resulting from the reduction in productivity. Estimates were based on multiple sources of information, including the National Epidemiological Study on Mental Health, the Hospital Morbidity Database, data from the Portuguese National Statistics Institute on population and causes of death, official data on wages, statistics on the pharmaceutical market, and qualified opinions of experts.

Results

The estimated prevalence of TRD, MDSR, and both types of depression combined was 79.4 thousand, 52.5 thousand, and 11.3 thousand patients, respectively. The disease burden (DALY) due to the disability generated by TRD alone, MDSR alone, and the joint prevalence was 25.2 thousand, 21 thousand, and 4.5 thousand, respectively, totaling 50.7 thousand DALYs. The disease burden due to premature death by suicide was 15.6 thousand DALYs. The estimated total disease burden was 66.3 thousand DALYs. In 2017, the annual direct costs with TRD and MDSR were estimated at € 30.8 million, with the most important components being medical appointments and medication. The estimated indirect costs were much higher than the direct costs. Adding work productivity losses due to reduced employment, absenteeism, presenteeism, and premature death, a total cost of € 1.1 billion was obtained.

Conclusions

Although TRD and MDSR represent relatively small direct costs for the health system, they have a relevant disease burden and extremely substantial productivity costs for the Portuguese economy and society, making TRD and MDSR priority areas for achieving health gains.

Epidemiology of treatment resistant depression among major depressive disorder patients in Israel

INTRODUCTION

Major depressive disorder (MDD) is one of the most common mental disorders worldwide, estimated to affect 10-15% of the population per year. Treatment resistant depression (TRD) is estimated to affect a third of these patients who show difficulties in social and occupational function, decline of physical health, suicidal thoughts and increased health care utilization. We describe the prevalence of MDD, TRD and associated healthcare resource utilization in Maccabi Healthcare Services (MHS), a 2.5 million-member state-mandated health service in Israel.

METHODS

All MHS members with an MDD diagnosis were identified within the years 2017-2018 and prevalence assessed by age, sex and TRD. To assess the incidence of MDD, members aged 18-65 years at the start of any MDD episode were identified between 1^st January 2016 and 31^st May 2018 with at least one systemic first-line antidepressant treatment within three months before or after the initial episode. Treatment patterns, time on first-line treatment, and healthcare resource utilization were compared by TRD.

RESULTS

A total of 4960 eligible MDD patients were identified (median age = 51 years, 65% female), representing a period prevalence of 0.218%, and of those, a high proportion of patients received drug treatment (92%). Among incident MDD cases (n = 2553), 24.4% had TRD. Factors associated with TRD included increasing age and personality disorder. Median time on treatment was 3.7 months (longer for those without TRD than those with) and 81.9% of patients purchased more than one month's supply of therapy. In the year after index, patients with TRD had a significant increased number of visits to primary care physicians, psychiatrists, emergency room visits, general hospitalizations, and psychiatric hospitalizations.

CONCLUSION

Our study shows that prevalence of MDD in Israel is low compared to other countries, however once diagnosed, patients' are likely to receive drug treatment. Among patients diagnosed with MDD, the proportion of TRD is similar to other countries, increases with age and is associated with increased healthcare utilization, therefore should be a focus of continued research for finding effective long term treatment options.

Courses of treatment and risk factors for treatment-resistant depression in Finnish primary and special healthcare: A nationwide cohort study

OBJECTIVE

Investigate incidence, risk factors and courses of treatment for treatment-resistant depression (TRD) in primary and special healthcare.

METHODS

All patients identified from nationwide registers, aged 16-65 years, diagnosed with depression in Finland during 2004-2016 were included. New antidepressant users were identified with six-month washout period and followed-up for two years to observe for presence of TRD, which was defined as initiation of a third trial after having failed two pharmacological treatment trials with adequate duration.

RESULTS

During follow-up, 177,144 persons had their first registered antidepressant treated depression (mean age: 39.5, 62.5% women). Of them, 10.9% (N = 19,322) met TRD criteria. Among the TRD patients, most common first and second antidepressants trials were: SSRIs (44.6%), mirtazapine (19.0%) and SNRIs (16.5%). As the third treatment line, antidepressant monotherapy (44.2% of TRD patients) was most common, followed by a combination of ≥2 antidepressants (32.1%), antipsychotic or mood stabilizer augmentation and an antidepressant (15.8%), both combination of antidepressants and an augmentation with a mood stabilizer or antipsychotic (4.9%), antipsychotic or mood stabilizer monotherapy (2.7%) and ECT (0.3%). Of TRD patients, 16.5% (N = 3188) progressed to the fifth treatment line, in which the most common treatments were antidepressant monotherapy (33.4%), antidepressant combinations (27.5%) and augmentation (24.2%). Factors associated with higher risk of TRD included male gender, younger age, higher initial disease severity and hospitalization at initial onset of depression.

CONCLUSIONS

Antidepressant monotherapies were still the most common fifth line of depression treatment. Severe depression, hospitalization due to depression, young age and male gender may predispose to TRD.

Clinical and societal burden of incident major depressive disorder: A population-wide cohort study in Stockholm

OBJECTIVE

Major depressive disorder (MDD) is a highly prevalent condition and a significant contributor to global disability. The vast majority of MDD is handled by primary care, but most real-life studies on MDD only include data from secondary care. The aim of this study was therefore to estimate the total clinical and societal burden of incident MDD including data from all healthcare levels in a large well-defined western European healthcare region.

METHODS

Population-wide observational study included healthcare data from Region Stockholm, Sweden's largest region with approximately 2.4 million inhabitants. All patients in Region Stockholm having their first unipolar MDD episode between January 1, 2012, and December 31, 2018, were included. The sample also included matched study population controls. Outcomes were psychiatric and non-psychiatric comorbid conditions, antidepressant therapy use, healthcare resource utilization, work loss, and all-cause mortality.

RESULTS

In the study period, 137,822 patients in Region Stockholm were diagnosed with their first unipolar MDD episode. Compared with matched controls, MDD patients had a higher burden of non-psychiatric and psychiatric comorbid conditions, 3.2 times higher outpatient healthcare resource utilization and 8.6 times more work loss. MDD was also associated with a doubled all-cause mortality compared with matched controls (HR: 2.2 [95% CI: 2.0-2.4]).

CONCLUSIONS

The high mortality, morbidity, healthcare resource utilization, and work loss found in this study confirms that MDD is associated with individual suffering and low functioning leading to substantial costs for patients and society. These findings should motivate additional efforts in improving outcomes for MDD patients.

Treatment-resistant depression and labor market affiliation in the Danish welfare society: a register-based study

PURPOSE

We explored if patients with treatment-resistant depression (TRD) go through different states of labor market affiliation during their course of illness before they return to work or obtain early retirement as compared to patients without TRD.

METHODS

All adults between 18 and 58 years with a first-time hospital contact due to depression in Danish patients' registers from 2000 to 2014 were followed in a nationwide labor market database. At time of TRD (index week), TRD patients were matched with patients without TRD in a 1:2 ratio. Sequence analysis and logistic regression were applied to explore the association of TRD and labor market affiliation and measures of transitions between labor market states 52 weeks before and after the index week.

RESULTS

At the index week, 14.1% of patients with TRD were in employment, whereas the proportion was 26.4% among non-TRD patients. Over time, the proportion of patients in employment increased slightly to 25.5% for TRD and 33.7% for non-TRD patients. The proportion of TRD patients with sickness absence at index was 47.0%, while the proportion was 26.2% for non-TRD patients. The adjusted odds of a below mean volatility of labor market transitions, characterized by more episodes in passive social transfer payments and disability pension, were higher among patients with TRD compared with non-TRD patients (OR 1.63, 95% CI [1.56-1.69]). Similarly, the adjusted odds of a below mean integration into employment were 1.63 higher among TRD patients compared with non-TRD patients (95% CI [1.56-1.70]).

CONCLUSION

Patients with TRD have higher levels of sickness absence and lower levels of reintegration into the labor market after meeting the criteria for TRD compared with patients without TRD.

One-year incidence rate of Treatment Resistant Depression (TRD) and treatment characteristics in China

BACKGROUND

Little is known about the characteristics of Treatment-Resistant Depression (TRD) in China. In previous studies various identification approaches have led to a wide range of results, and it is unclear how Chinese patients compare to those in other studies.

METHODS

This is a retrospective cohort study using electronic health records (EHR) from two major psychiatric hospitals in China. Adult major depressive disorder (MDD) patients who initiated pharmaceutical treatment during 2010-2018 were enrolled and follow-up was 1 year. TRD was primarily identified by consensus definition of two failures of adequate (≥4 weeks) regimens. Alternative regimens of 2-weeks and 6-weeks duration, and a data-driven definition were also applied.

RESULTS

In the two hospitals, 12,257 (mean age: 40.8y, 63.6% female) and 8314 (mean age: 42.4y, 68.4% female) eligible patients were included. The 1-year incidence rate of TRD was estimated to be 5.2%-7.7% using the primary definition. TRD patients had mean treatment duration of 302.5 days and 285.7 days; had 3.6 and 3.7 treatment steps on average; 94.0% and 72.6% were prescribed polypharmacy regimens, which were all marginally greater than that of non-TRD patients. Alternative definitions resulted in a wide range of incidence estimates (0.5%-20.0%).

LIMITATIONS

Medications were assumed to be consumed as prescribed and lack of rating scales from EHRs may limit our TRD identification.

CONCLUSIONS

The incidence of TRD among Chinese MDD patients was comparable to other countries under similar settings and more complex treatment characteristics were observed among TRD patients. Alternative TRD definitions revealed the need for better treatment management in practices.

Health-related quality of life burden associated with treatment-resistant depression in UK patients: Quantitative results from a mixed-methods non-interventional study

BACKGROUND

Major depressive disorder (MDD) and its more intractable variant, treatment-resistant depression (TRD), are common conditions that adversely affect patient well-being and health-related quality of life (HRQoL). This study aimed to quantify the impact of MDD and particularly TRD on the HRQoL, functioning and productivity of UK patients to support clinical and reimbursement decisions and policymaking.

METHODS

148 patients with clinician-verified symptomatic (non-treatment-resistant) MDD (Patients-MDD; n = 61) or TRD (Patients-TRD; n = 87) were recruited from ten clinical sites. Participants completed validated patient-reported outcome measures assessing depressive symptom severity (Patient Health Questionnaire-9 [PHQ-9]), HRQoL (EQ-5D-5 L/abbreviated World Health Organization Quality of Life Questionnaire [WHOQOL-BREF]) and work productivity/activity impairment (WPAI:D).

RESULTS

Patients-TRD and Patients-MDD reported similar levels of depressive symptom severity (mean PHQ-9 16.2/16.6, respectively). However, HRQoL was significantly poorer for Patients-TRD compared with Patients-MDD, both in the overall cohort (median EQ-5D-5 L utility 0.606/0.721, respectively [p = 0.021]; WHOQOL-BREF overall score 55.2/58.8 [p = 0.024]) and in patients with a PHQ-9 score ≥15 (median EQ-5D-5 L utility 0.415/0.705, respectively [p<0.001]). Although a numerically lower proportion of Patients-TRD were employed (45% vs 57% of Patients-MDD; p = 0.204), employed Patients-MDD reported significantly higher absenteeism and work productivity loss.

LIMITATIONS

A minority of patients screened as having symptomatic MDD or TRD self-reported low PHQ-9 symptom severity. This was addressed with a subgroup analysis of patients with more severe depression.

CONCLUSIONS

TRD is associated with an added patient HRQoL burden, above that observed for non-treatment-resistant MDD. This highlights the unmet need for greater access to improved treatment, including new treatment options for Patients-TRD.

Real-World Treatment Patterns, Outcomes, Resource Utilization and Costs in Treatment-Resistant Major Depressive Disorder: PATTERN, a Retrospective Cohort Study in Belgium

OBJECTIVE

Treatment-resistant depression (TRD), a subgroup of major depressive disorder (MDD) that does not adequately respond to treatment, has a substantial impact on the quality of life of patients and is associated with higher medical and mental health care costs. This study aimed to report real-world treatment patterns, outcomes, resource utilization, and costs in the management of TRD by psychiatrists in Belgium.

METHODS

We conducted a retrospective, non-interventional cohort study of patients ≥ 18 years, with diagnosed MDD who are treatment-resistant, defined as not responding to two different antidepressant treatments in the current moderate to severe major depressive episode (MDE). Data obtained from medical records of patients included patient health state (MDE, response, remission, and recovery) and resource use (number of consultations and emergency room visits, non-drug and drug interventions, and hospitalizations).

RESULTS

One hundred and twenty-five patients were enrolled in nine sites, with an average observation period of 34 months. During the MDE, 89.7% of patients were treated with selective serotonin reuptake inhibitors, 63.2% with serotonin-norepinephrine reuptake inhibitors, and 60.8% with anti-psychotics. Twenty-four percent of patients did not respond to any treatment; 76% responded, of whom 61% experienced a relapse; 28% of patients reached recovery, of whom 31.4% experienced recurrence. The average yearly direct cost of a TRD patient is €9012, mainly driven by hospitalization in the MDE. The observed absenteeism relates to a high indirect cost, representing 70% of the total MDE cost.

CONCLUSION

TRD is associated with a high unmet need and economic burden for patients and society, with highest costs in the MDE health state driven by absenteeism.

Clinical research challenges posed by difficult-to-treat depression

Approximately one-third of individuals in a major depressive episode will not achieve sustained remission despite multiple, well-delivered treatments. These patients experience prolonged suffering and disproportionately utilize mental and general health care resources. The recently proposed clinical heuristic of 'difficult-to-treat depression' (DTD) aims to broaden our understanding and focus attention on the identification, clinical management, treatment selection, and outcomes of such individuals. Clinical trial methodologies developed to detect short-term therapeutic effects in treatment-responsive populations may not be appropriate in DTD. This report reviews three essential challenges for clinical intervention research in DTD: (1) how to define and subtype this heterogeneous group of patients; (2) how, when, and by what methods to select, acquire, compile, and interpret clinically meaningful outcome metrics; and (3) how to choose among alternative clinical trial design options to promote causal inference and generalizability. The boundaries of DTD are uncertain, and an evidence-based taxonomy and reliable assessment tools are preconditions for clinical research and subtyping. Traditional outcome metrics in treatment-responsive depression may not apply to DTD, as they largely reflect the only short-term symptomatic change and do not incorporate durability of benefit, side effect burden, or sustained impact on quality of life or daily function. The trial methodology will also require modification as trials will likely be of longer duration to examine the sustained impact, raising complex issues regarding control group selection, blinding and its integrity, and concomitant treatments.

Treatment-Resistant Depression in Poland—Epidemiology and Treatment

(1) Background: Major depressive disorder (MDD) is one of the most prevalent psychiatric disorders worldwide. Although several antidepressant drugs have been developed, up to 30% of patients fail to achieve remission, and acute remission rates decrease with the number of treatment steps required. The aim of the current project was to estimate and describe the population of treatment-resistant depression (TRD) patients in outpatient clinics in Poland. (2) Methods: The project involved a representative sample of psychiatrists working in outpatient clinics, chosen through a process of quota random sampling. The doctors completed two questionnaires on a consecutive series of patients with MDD, which captured the patients’ demographics, comorbidities, and medical histories. TRD was defined as no improvement seen after a minimum of two different antidepressant drug therapies applied in sufficient doses for a minimum of 4 weeks each. The data were weighted and extrapolated to the population of TRD outpatients in Poland. (3) Results: A total of 76 psychiatrists described 1781 MDD patients, out of which 396 fulfilled the criteria of TRD. The TRD patients constituted 25.2% of all MDD patients, which led to the number of TRD outpatients in Poland being estimated at 34,800. The demographics, comorbidities, medical histories, and histories of treatment of Polish TRD patients were described. In our sample of the TRD population (mean age: 45.6 ± 13.1 years; female: 64%), the patients had experienced 2.1 ± 1.6 depressive episodes (including the current one), and the mean duration of the current episode was 4.8 ± 4.4 months. In terms of treatment strategies, most patients (around 70%) received monotherapy during the first three therapies, while combination antidepressant drugs (ADs) were applied more often from the fourth line of treatment. The use of additional medications and augmentation was reported in only up to one third of the TRD patients. During all of the treatment steps, patients most often received a selective serotonin reuptake inhibitor (SSRI) and a serotonin norepinephrine reuptake inhibitor (SNRI). (4) Conclusions: TRD is a serious problem, affecting approximately one fourth of all depressive patients and nearly 35,000 Poles.

Reviewing the Role of the Endocannabinoid System in the Pathophysiology of Depression

Major depressive disorder is a high-impact, debilitating disease and it is currently considered the most prevalent mental illness. It is associated with disability, as well as increased morbidity and mortality. Despite its significant repercussions in our society, its exact pathophysiology remains unclear and therefore, available antidepressant treatment options are limited and, in some cases, ineffective. In the past years, research has focused on the development of a multifactorial theory of depression. Simultaneously, evidence supporting the role of the endocannabinoid system in the neurobiology of neuropsychiatric diseases has emerged. Studies have shown that the endocannabinoid system strongly impacts neurotransmission, and the neuroendocrine and neuroimmune systems, which are known to be dysfunctional in depressive patients. Accordingly, common antidepressants were shown to have a direct impact on the expression of cannabinoid receptors throughout the brain. Therefore, the relationship between the endocannabinoid system and major depressive disorder is worth consideration. Nevertheless, most studies focus on smaller pieces of what is undoubtedly a larger mosaic of interdependent processes. Therefore, the present review summarizes the existing literature regarding the role of the endocannabinoid system in depression aiming to integrate this information into a holistic picture for a better understanding of the relationship between the two.

Prevalence and Impact of Treatment-Resistant Depression in Latin America: a Prospective, Observational Study

Approximately one-third of patients with major depressive disorder (MDD) have treatment-resistant depression (TRD). The TRAL study will evaluate the prevalence and impact of TRD among patients with MDD in four Latin American countries. In this multicenter, prospective, observational study, patients with MDD were recruited from 33 reference sites in Mexico, Colombia, Brazil, and Argentina. Patients were assessed for TRD, defined as failure to respond to ≥ 2 antidepressant medications of adequate dose and duration. Demographics, previous/current treatments, depressive symptoms, functioning, healthcare resource utilization, and work impairment were also collected and evaluated using descriptive statistics, chi-square test, Fisher exact test, t-test for independent samples, or the Mann-Whitney nonparametric test, as appropriate. 1475 patients with MDD were included in the analysis (mean age, 45.6 years; 78% women); 89% were receiving relevant psychiatric treatment. 429 patients met criteria for TRD, and a numerically higher proportion of patients with TRD was present in public versus private sites of care (31% vs 27%). The mean Montgomery-Asberg Depression Rating Scale score was 25.0 among all MDD patients and was significantly higher for patients with TRD versus non-TRD (29.4 vs 23.3; P < 0.0001). Patients with TRD, versus those with non-TRD, were significantly more likely to be older, have a longer disease duration, have more comorbidities, be symptomatic, have a higher median number of psychiatric consultations, and report greater work impairment. Patients with TRD have a disproportionate burden of disease compared to those with non-TRD. Appropriate treatment for TRD is a substantial unmet need in Latin America. https://www.ClinicalTrials.gov identifier NCT03207282, 07/02/2017.

Ketamine and other glutamate receptor modulators for depression in adults with bipolar disorder

BACKGROUND

Glutamergic system dysfunction has been implicated in the pathophysiology of bipolar depression. This is an update of the 2015 Cochrane Review for the use of glutamate receptor modulators for depression in bipolar disorder.

OBJECTIVES

1. To assess the effects of ketamine and other glutamate receptor modulators in alleviating the acute symptoms of depression in people with bipolar disorder. 2. To review the acceptability of ketamine and other glutamate receptor modulators in people with bipolar disorder who are experiencing depressive symptoms.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase and PsycINFO all years to July 2020.  We did not apply any restrictions to date, language or publication status.

SELECTION CRITERIA

RCTs comparing ketamine or other glutamate receptor modulators with other active psychotropic drugs or saline placebo in adults with bipolar depression.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion, assessed trial quality and extracted data. Primary outcomes were response rate and adverse events. Secondary outcomes included remission rate, depression severity change scores, suicidality, cognition, quality of life, and dropout rate. The GRADE framework was used to assess the certainty of the evidence.

MAIN RESULTS

Ten studies (647 participants) were included in this review (an additional five studies compared to the 2015 review). There were no additional studies added to the comparisons identified in the 2015 Cochrane review on ketamine, memantine and cytidine versus placebo. However, three new comparisons were found: ketamine versus midazolam, N-acetylcysteine versus placebo, and riluzole versus placebo. The glutamate receptor modulators studied were ketamine (three trials), memantine (two), cytidine (one), N-acetylcysteine (three), and riluzole (one). Eight of these studies were placebo-controlled and two-armed. In seven trials the glutamate receptor modulators had been used as add-on drugs to mood stabilisers. Only one trial compared ketamine with an active comparator, midazolam. The treatment period ranged from a single intravenous administration (all ketamine studies), to repeated administration for riluzole, memantine, cytidine, and N-acetylcysteine (with a follow-up of eight weeks, 8 to 12 weeks, 12 weeks, and 16 to 20 weeks, respectively). Six of the studies included sites in the USA, one in Taiwan, one in Denmark, one in Australia, and in one study the location was unclear. All participants had a primary diagnosis of bipolar disorder and were experiencing an acute bipolar depressive episode, diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders fourth edition (IV) or fourth edition text revision (IV-TR). Among all glutamate receptor modulators included in this review, only ketamine appeared to be more efficacious than placebo 24 hours after infusion for response rate (odds ratio (OR) 11.61, 95% confidence interval (CI) 1.25 to 107.74; P = 0.03; participants = 33; studies = 2; I² = 0%, low-certainty evidence). Ketamine seemed to be more effective in reducing depression rating scale scores (MD -11.81, 95% CI -20.01 to -3.61; P = 0.005; participants = 32; studies = 2; I2 = 0%, very low-certainty evidence). There was no evidence of ketamine's efficacy in producing remission over placebo at 24 hours (OR 5.16, 95% CI 0.51 to 52.30; P = 0.72; participants = 33; studies = 2; I2 = 0%, very low-certainty evidence). Evidence on response, remission or depression rating scale scores between ketamine and midazolam was uncertain at 24 hours due to very low-certainty evidence (OR 3.20, 95% CI 0.23 to 45.19). In the one trial assessing ketamine and midazolam, there were no dropouts due to adverse effects or for any reason (very low-certainty evidence). Placebo may have been more effective than N-acetylcysteine in reducing depression rating scale scores at three months, although this was based on very low-certainty evidence (MD 1.28, 95% CI 0.24 to 2.31; participants = 58; studies = 2). Very uncertain evidence found no difference in response at three months (OR 0.82, 95% CI 0.32 to 2.14; participants = 69; studies = 2; very low-certainty evidence). No data were available for remission or acceptability. Extremely limited data were available for riluzole vs placebo, finding only very-low certainty evidence of no difference in dropout rates (OR 2.00, 95% CI 0.31 to 12.84; P = 0.46; participants = 19; studies = 1; I2 = 0%).

AUTHORS' CONCLUSIONS

It is difficult to draw reliable conclusions from this review due to the certainty of the evidence being low to very low, and the relatively small amount of data usable for analysis in bipolar disorder, which is considerably less than the information available for unipolar depression. Nevertheless, we found uncertain evidence in favour of a single intravenous dose of ketamine (as add-on therapy to mood stabilisers) over placebo in terms of response rate up to 24 hours, however ketamine did not show any better efficacy for remission in bipolar depression. Even though ketamine has the potential to have a rapid and transient antidepressant effect, the efficacy of a single intravenous dose may be limited. We did not find conclusive evidence on adverse events with ketamine, and there was insufficient evidence to draw meaningful conclusions for the remaining glutamate receptor modulators. However, ketamine's psychotomimetic effects (such as delusions or delirium) may have compromised study blinding in some studies, and so we cannot rule out the potential bias introduced by inadequate blinding procedures. To draw more robust conclusions, further methodologically sound RCTs (with adequate blinding) are needed to explore different modes of administration of ketamine, and to study different methods of sustaining antidepressant response, such as repeated administrations.

Bidirectional associations between treatment-resistant depression and general medical conditions

Depression is associated with general medical conditions (GMCs), but it is not known if treatment-resistant depression (TRD) affects GMC risk and vice versa. We estimated bidirectional associations between TRD and GMCs (prior and subsequent). All individuals aged 18-69 years, born and living in Denmark, with a first-time prescription for an antidepressant between 2005 and 2012 were identified in the Danish Prescription Registry (N = 154,513). TRD was defined as at least two shifts in treatment regimes. For prior GMCs, we estimated odds ratios (ORs) using conditional logistic regression comparing TRD patients with matched non-TRD controls adjusted for other GMCs and number of other GMCs. For subsequent GMCs, we used Cox regression to calculate hazard ratios (HRs) in TRD vs. non-TRD patients adjusted for age at first prescription, calendar time, other GMCs and number of other GMCs. Patients with TRD had higher prevalence of prior GMCs related to the immune or neurological systems; musculoskeletal disorders (women aOR: 1.35, 95% CI: 1.26-1.46, men aOR: 1.30, 95% CI: 1.19-1.42) and migraine (women aOR: 1.22, 95% CI: 1.09-1.36, men aOR: 1.25, 95% CI: 1.00-1.56). Subsequent GMCs were related to a broader spectrum; cardiovascular (women aHR: 1.43, 95% CI: 1.32-1.54, men aHR: 1.31, 95% CI: 1.19-1.43), endocrine (women aHR: 1.52, 95% CI: 1.37-1.67, men aHR: 1.24, 95% CI: 1.07-1.44), and neurological disorders (women aHR: 1.24, 95% CI: 1.13-1.35, men aHR: 1.19, 95% CI: 1.07-1.34). Our study presents a broad overview of comorbid medical conditions in patients with TRD and further studies are needed to explore the associations in detail.

Prevalence of Pre-existing Conditions Relevant for Adverse Events and Potential Drug-Drug Interactions Associated with Augmentation Therapies Among Patients with Treatment-Resistant Depression

INTRODUCTION

Pre-existing conditions relevant for adverse events (AE) and the potential for drug-drug interactions (DDIs) may limit safe pharmacotherapeutic augmentation options for patients with major depressive disorder (MDD). This concern may be heightened among patients with treatment-resistant depression (TRD), who often have comorbid medical disorders.

METHODS

Adults with MDD and ≥ 1 antidepressant claim within the first observed major depressive episode were identified in the MarketScan® Databases. Those initiating a new regimen after two regimens at adequate dose and duration were considered to have TRD. The index date was defined at TRD onset or on a random antidepressant claim among patients with non-TRD MDD. Pre-existing conditions 12 months pre-index and potential DDIs 3 months pre/post-index associated with specific non-antidepressant augmentation therapies, including atypical antipsychotics (APs), buspirone, psychostimulants, anticonvulsants, thyroid hormone, and lithium were compared between 1:1 matched TRD and non-TRD MDD cohorts.

RESULTS

Overall, 3414 patients with TRD and non-TRD MDD (mean age 39.7 years, 69% female) were matched. Relative to non-TRD MDD, patients with TRD had 33% higher likelihood of ≥ 1 pre-existing condition relevant for AEs listed in product labels of non-antidepressant augmentation therapies (p < 0.001). Patients with TRD vs. non-TRD MDD had 12.9 and 6.4 times higher likelihood of ≥ 2 and ≥ 3 DDIs, respectively, based on their medication regimen (all p < 0.001).

CONCLUSION

Pre-existing conditions relevant for listed AEs and potential DDIs limit safe augmentation options in MDD, particularly among patients with TRD. Payer prior authorization policies requiring several augmentation therapy trials to access novel treatments may complicate clinical management of this population.

Economic burden of treatment-resistant depression among veterans in the United States

OBJECTIVE

Evidence is limited on the economic burden associated with treatment-resistant depression (TRD) among US veterans. We evaluated the economic burden among patients with major depressive disorder (MDD) with and without TRD, and those without MDD in the Veterans Health Administration (VHA).

METHODS

Three cohorts were identified using VHA claims data (01APR2014-31MAR2018). Patients with MDD (aged ≥18) who failed ≥2 antidepressant treatments of adequate dose and duration were defined as having TRD; patients with MDD not meeting this criterion constituted the non-TRD MDD cohort (index: first antidepressant claim). The non-MDD cohort included those without MDD diagnosis (index: randomly assigned). Patients with psychosis, schizophrenia, manic/bipolar disorder, or dementia in the 6-month pre-index period were excluded. Patients with non-TRD MDD and non-MDD were matched 1:1 to patients with TRD based on demographic characteristics (age, gender, race, index year). Health care resource utilization (HRU) and costs were analyzed during the post-index period using a negative binomial model and ordinary least squares regression model, respectively.

RESULTS

After 1:1 exact matching, 10,449 patients were included in each cohort (mean age: 48.9 years). Patients with TRD had higher per patient per year (PPPY) HRU than non-TRD MDD (all-cause inpatient visits: incidence rate ratio [IRR]: 1.70 [95% confidence interval: 1.57-1.83]) and non-MDD (IRR: 5.04 [95% confidence interval: 4.51-5.63]), and incurred higher total all-cause health care costs PPPY than non-TRD MDD (mean difference: $5,906) and non-MDD (mean difference: $11,873; all p<.0001).

CONCLUSION

Among US veterans, TRD poses a significant incremental economic burden relative to non-TRD MDD and non-MDD.

Exploring real-world evidence to uncover unknown drug benefits and support the discovery of new treatment targets for depressive and bipolar disorders

BACKGROUND

Major depressive and bipolar disorders are associated with impaired quality of life and high economic burden. Although progress has been made in our understanding of the underlying pathophysiology and the development of novel pharmacological treatments, a large unmet need remains for finding effective treatment options. The purpose of this study was to identify potential new mechanisms of actions or treatment targets that could inform future research and development opportunities for major depressive and bipolar disorders.

METHODS

A self-controlled cohort study was conducted to examine associations between 1933 medications and incidence of major depressive and bipolar disorders across four US insurance claims databases. Presence of incident depressive or bipolar disorders were captured for each patient prior to or after drug exposure and incident rate ratios were calculated. Medications that demonstrated ≥50% reduction in risk for both depressive and bipolar disorders within two or more databases were evaluated as potential treatment targets.

RESULTS

Eight medications met our inclusion criteria, which fell into three treatment groups: drugs used in substance use disorders; drugs that affect the cholinergic system; and drugs used for the management of cardiovascular-related conditions.

LIMITATIONS

This study was not designed to confirm a causal association nor inform current clinical practice. Instead, this research and the methods employed intended to be hypothesis generating and help uncover potential treatment pathways that could warrant further investigation.

CONCLUSIONS

Several potential drug targets that could aid further research and discovery into novel treatments for depressive and bipolar disorders were identified.

Genetic and clinical characteristics of treatment-resistant depression using primary care records in two UK cohorts

Treatment-resistant depression (TRD) is a major contributor to the disability caused by major depressive disorder (MDD). Primary care electronic health records provide an easily accessible approach to investigate TRD clinical and genetic characteristics. MDD defined from primary care records in UK Biobank (UKB) and EXCEED studies was compared with other measures of depression and tested for association with MDD polygenic risk score (PRS). Using prescribing records, TRD was defined from at least two switches between antidepressant drugs, each prescribed for at least 6 weeks. Clinical-demographic characteristics, SNP-based heritability (h²_SNP) and genetic overlap with psychiatric and non-psychiatric traits were compared in TRD and non-TRD MDD cases. In 230,096 and 8926 UKB and EXCEED participants with primary care data, respectively, the prevalence of MDD was 8.7% and 14.2%, of which 13.2% and 13.5% was TRD, respectively. In both cohorts, MDD defined from primary care records was strongly associated with MDD PRS, and in UKB it showed overlap of 71-88% with other MDD definitions. In UKB, TRD vs healthy controls and non-TRD vs healthy controls h²_SNP was comparable (0.25 [SE = 0.04] and 0.19 [SE = 0.02], respectively). TRD vs non-TRD was positively associated with the PRS of attention deficit hyperactivity disorder, with lower socio-economic status, obesity, higher neuroticism and other unfavourable clinical characteristics. This study demonstrated that MDD and TRD can be reliably defined using primary care records and provides the first large scale population assessment of the genetic, clinical and demographic characteristics of TRD.

Real-world evidence from a European cohort study of patients with treatment resistant depression: Treatment patterns and clinical outcomes

BACKGROUND

Treatment resistant depression (TRD) characterizes a subgroup of 10-30% of patients with major depressive disorder, and is associated with considerable morbidity and mortality. A consensus treatment for TRD does not exist, which often leads to wide variations in treatment strategies. Real-world studies on treatment patterns and outcomes in TRD patients in Europe are lacking and could help elucidate current treatment strategies and their efficacy.

METHODS

This non-interventional cohort study of patients with TRD (defined as treatment failure on ≥2 oral antidepressants given at adequate dose and duration) with moderate to severe depression collected real-world data on treatment patterns and outcomes in several European countries. Patients were started on a new treatment for depression according to routine clinical practice.

RESULTS

Among 411 patients enrolled, after 6 months, only 16.7% achieved remission and 73.5% showed no response. At Month 12, while 19.2% achieved remission and 69.2% showed no response, 33.3% of those in remission at Month 6 were no longer in remission. Pharmacological treatments employed were heterogenous; 54 different drugs were recorded at baseline, and the top 5 treatment types according to drug classes accounted for 40.0% of patients. Even though remission rates were very low, at Month 12, 60.0% of patients had not changed treatment since enrolment.

CONCLUSIONS

The heterogeneity of treatments highlights a lack of consensus. Moreover, despite low response rates, patients often remained on treatments for substantial periods of time. These data further support existence of an unmet treatment need for TRD patients in Europe.

Economic Burden of Treatment-Resistant Depression among Adults with Chronic Non-Cancer Pain Conditions and Major Depressive Disorder in the US

OBJECTIVE

Major depressive disorder (MDD) and chronic non-cancer pain conditions (CNPC) often co-occur and exacerbate one another. Treatment-resistant depression (TRD) in adults with CNPC can amplify the economic burden. This study examined the impact of TRD on direct total and MDD-related healthcare resource utilization (HRU) and costs among commercially insured patients with CNPC and MDD in the US.

METHODS

The retrospective longitudinal cohort study employed a claims-based algorithm to identify adults with TRD from a US claims database (January 2007 to June 2017). Costs (2018 US$) and HRU were compared between patients with and without TRD over a 12-month period after TRD/non-TRD index date. Counterfactual recycled predictions from generalized linear models were used to examine associations between TRD and annual HRU and costs. Post-regression linear decomposition identified differences in patient-level factors between TRD and non-TRD groups that contributed to the excess economic burden of TRD.

RESULTS

Of the 21,180 adults with CNPC and MDD, 10.1% were identified as having TRD. TRD patients had significantly higher HRU, translating into higher average total costs (US$21,015_TRD vs US$14,712_{No TRD}) and MDD-related costs (US$1201_TRD vs US$471_{No TRD}) compared with non-TRD patients (all p < 0.001). Prescription drug costs accounted for 37.6% and inpatient services for 30.7% of the excess total healthcare costs among TRD patients. TRD patients had a significantly higher number of inpatient (incidence rate ratio [IRR] 1.30, 95% CI 1.14-1.47) and emergency room visits (IRR 1.21, 95% CI 1.10-1.34) than non-TRD patients. Overall, 46% of the excess total costs were explained by differences in patient-level characteristics such as polypharmacy, number of CNPC, anxiety, sleep, and substance use disorders between the TRD and non-TRD groups.

CONCLUSION

TRD poses a substantial direct economic burden for adults with CNPC and MDD. Excess healthcare costs may potentially be reduced by providing timely interventions for several modifiable risk factors.

Treatment patterns in patients with treatment-resistant depression in Danish patients with major depressive disorder

OBJECTIVE

To describe treatment patterns in patients with treatment-resistant depression (TRD) and major depressive disorder (MDD) stratified by depression severity and year of diagnosis. Patterns of treatment were also compared to country-specific guidelines.

METHODS

All adults registered first time with a hospital contact due to MDD from 1996 through 2015 were identified and followed for all dispensed prescriptions of antidepressants, antipsychotics, lithium, initiation of electroconvulsive therapy (ECT), and psychotherapy in Danish registers 12 months before and after their hospital MDD diagnosis. TRD was characterized by two shifts in treatment.

RESULTS

We identified 197,615 patients of whom 15% developed TRD. In total, 88% of patients started treatment with antidepressants or ECT. Selective serotonin reuptake inhibitors (SSRIs) were the most frequently used treatment during the study period and more than half (50.7%) of patients changed treatment at least once. Among patients with TRD, serotonin and noradrenaline reuptake inhibitors (SNRIs) were the most frequently used treatment (55.9%), and 37.0% initiated a new treatment the following year. SSRIs and SNRIs were part of most combinations of treatment, regardless of depression severity, year of diagnosis, or presence of TRD.

CONCLUSION

15% of patients met the criteria for TRD. Irrespective of patient characteristics and year of diagnosis, SSRIs and SNRIs are the most used treatments for depression, even after patients met the criteria for TRD. We confirm that guidelines for first treatment were followed for most patients diagnosed with MDD in Denmark, but for patients with TRD, choice of treatment was arbitrary.

Using a machine learning approach to investigate factors associated with treatment-resistant depression among adults with chronic non-cancer pain conditions and major depressive disorder

OBJECTIVE

Presence of chronic non-cancer pain conditions (CNPC) among adults with major depressive disorder (MDD) may reduce benefits of antidepressant therapy, thereby increasing the possibility of treatment resistance. This study sought to investigate factors associated with treatment-resistant depression (TRD) among adults with MDD and CNPC using machine learning approaches.

METHODS

This retrospective cohort study was conducted using a US claims database which included adults with newly diagnosed MDD and CNPC (January 2007-June 2017). TRD was identified using a clinical staging algorithm for claims data. Random forest (RF), a machine learning method, and logistic regression was used to identify factors associated with TRD. Initial model development included 42 known and/or probable factors that may be associated with TRD. The final refined model included 20 factors.

RESULTS

Included in the sample were 23,645 patients (73% female mean age: 55 years; 78% with ≥2 CNPC, and 91% with joint pain/arthritis). Overall, 11.4% adults (N = 2684) met selected criteria for TRD. The five leading factors associated with TRD were the following: mental health specialist visits, polypharmacy (≥5 medications), psychotherapy use, anxiety, and age. Cross-validated logistic regression model indicated that those with TRD were younger, more likely to have anxiety, mental health specialist visits, polypharmacy, and psychotherapy use with adjusted odds ratios (AORs) ranging from 1.93 to 1.27 (all ps < .001).

CONCLUSION

Machine learning identified several factors that warrant further investigation and may serve as potential targets for clinical intervention to improve treatment outcomes in patients with TRD and CNPC.

Real-world evidence from a European cohort study of patients with treatment resistant depression: Baseline patient characteristics

BACKGROUND

Treatment resistant depression (TRD; failure to respond to ≥2 treatments) affects ~20% of patients with major depressive disorder (MDD). Real-world data could help describe patient characteristics and TRD disease burden, to assess the unmet needs of TRD patients in Europe.

METHODS

This observational study collected data from adults with moderate to severe TRD initiating a new treatment for depression, according to local standards of care. At baseline, socio-demographic characteristics, medical history, prior and current treatments were recorded. Disease severity, health-related quality of life (HRQoL), functionality and productivity were assessed.

RESULTS

Overall, 411 eligible patients were enrolled across seven European countries. Mean (standard deviation [SD]) patient age was 51.0 (10.8) years; 62.3% were female. Long-term sick leave was reported by 19.0% of patients; 30.2% were unemployed. The mean (SD) duration of the current episode was 2.6 (3.9) years. At baseline, mean (SD) HRQoL scores for EuroQoL 5-dimension 5-level (UK tariff) and EQ-Visual Analog Scale were 0.41 (0.25) and 41.1 (18.7), respectively. The Work Productivity and Activity Impairment questionnaire demonstrated mean (SD) absenteeism of 57.0% (44.9%) and presenteeism of 54.7% (29.5%); mean (SD) overall work impairment was 60.5% (29.9%).

LIMITATIONS

Key limitations are small cohort size, absence of a control group and generalizability to countries with different healthcare models.

CONCLUSIONS

TRD patients had a high disease burden, low HRQoL and reduced function and productivity, with a substantial proportion unable to work. This demonstrates an unmet treatment need in TRD patients that, if addressed, could reduce the heavy personal and societal burden.

Cause-specific life years lost in individuals with treatment-resistant depression: A Danish nationwide register-based cohort study

BACKGROUND

Depression is associated with excess mortality, but it is not known how treatment-resistance influences life expectancy. We estimated cause-specific excess mortality and Life Years Lost (LYL) in patients with treatment-resistant depression (TRD).

METHODS

The population included all individuals born and living in Denmark who redeemed their first prescription for an antidepressant at age 18-69 years between 2005 and 2012, identified in the Danish National Prescription Registry. TRD was defined as at least two additional and different antidepressant trials within two years. Mortality rate ratios (MRRs) were estimated with Cox regression adjusted for age at first prescription, calendar year and comorbidity. Differences in life expectancy were estimated by the Life Years Lost (LYL) method.

RESULTS

The cohort included 154,513 first-time pharmacologically treated patients with depression, of whom 8,294 (5.4%) were identified as having TRD. Patients were followed for 1,032,245 person-years during which 9,795 deaths occurred. Men and women with TRD had significantly higher mortality than non-TRD (aMRR: 1.34, 95% CI 1.18-1.52 and aMRR: 1.39, 95% CI 1.19-1.63, respectively). Life expectancy for men and women with TRD was 1.21 (95% CI 0.36-2.44) and 1.24 (95% CI 0.35-2.34) years shorter than in all patients with depression. Suicide accounted for the majority of excess LYL, with 1.10 (95% CI 0.46-1.61) years in men and 0.82 (95% CI 0.44-1.27) years in women with TRD.

LIMITATIONS

Using redeemed prescriptions to define TRD may increase the risk of misclassification.

CONCLUSIONS

Patients not responding adequately to several treatment trials are at increased risk for premature death, particularly suicide.

Clinical characteristics of treatment-resistant depression in adults in Hungary: Real-world evidence from a 7-year-long retrospective data analysis

Purpose

Treatment-resistant depression (TRD) is associated with a poor quality of life and high economic burden. This observational retrospective epidemiological study aimed to estimate the proportion of patients with TRD within a cohort of patients with major depressive disorder (MDD) in Hungary and examine the mortality and comorbidities of patients with and without TRD.

Patients and methods

This study included patients with MDD who experienced onset of a new depressive episode between 01 January 2009 and 31 August 2015, using data from a nationwide, longitudinal database.

Results

Overall, 99,531 patients were included in the MDD cohort, of which 8,268 (8.3%) also met the criteria for TRD. The overall survival of non-TRD patients was longer than in TRD patients; the risk of mortality for TRD patients was significantly higher than of non-TRD patients (HR [CI] 1.381 [1.212–1.571]; p<0.001). Patients with TRD had a significantly higher probability of having “Neurotic, stress-related and somatoform disordersˮ, autoimmune conditions, cardio- or cerebrovascular diseases, thyroid gland diseases and self-harming behaviour not resulting in death than non-TRD patients (for all comparisons, p values were less than 0.005).

Discussion

To our best knowledge, this is the first study to assess the frequency of TRD in Hungary. In a cohort of Hungarian MDD patients, we have found that the proportion of TRD (~8.3%) is comparable to those reported in previous studies with similar methodology from other countries. The majority of our other main findings (e.g. more frequent self-harming behaviour, increased risk of “Neurotic, stress-related and somatoform disordersˮ and higher overall mortality in TRD subjects) are also in line with previous results from other countries. Taking the substantial proportion of patients with TRD into consideration, a more comprehensive and targeted treatment strategy would be required for these individuals.

Excess deaths in treatment-resistant depression

BACKGROUND

Patients with treatment-resistant depression (TRD) have an increased mortality risk compared with other patients with depression, but it is not known how this translates into absolute numbers of excess deaths.

METHODS

Swedish national registers were used to identify a cohort of 118,774 antidepressant initiators 18-69 years old with a depression diagnosis. Patients who initiated a third consecutive treatment trial were classified as having TRD. Flexible parametric survival models were used to estimate the mortality risk due to all causes and external causes (suicides and accidents), comparing TRD patients with patients with other depression while adjusting for clinical and sociodemographic covariates and including interactions with TRD, age, and Charlson comorbidity index (CCI) for a number of somatic comorbidities. Standardized survival was estimated, as were numbers of excess deaths among TRD patients within each age and comorbidity category.

RESULTS

Compared with the mortality risk of other depressed patients, patients with TRD experienced excess deaths in most age and comorbidity categories in the range of 7-16 deaths per 1000 patients during 5 years. Highest numbers for all-cause excess deaths were found among patients 18-29 years old with CCI 1, where 16 [95% confidence interval 5-28] of the expected 37 [25-48] deaths per 1000 patients were excess deaths. The majority of the excess deaths were due to external causes.

CONCLUSION

Patients with TRD experience significant numbers of excess deaths compared with other patients with depression.

Economic burden of treatment-resistant depression in privately insured US patients with co-occurring anxiety disorder and/or substance use disorder

OBJECTIVE

To assess the burden of treatment-resistant depression (TRD) among privately insured patients with anxiety disorder and/or substance use disorders (SUD).

METHODS

Adults <65 years old were identified in the Optum Health Care Solutions Inc. database (July 2009-March 2017). Among those with major depressive disorder (MDD) and antidepressant use, patients who initiated a third antidepressant (index date) after two regimens at adequate dose and duration were classified in the TRD cohort and patients without evidence of TRD were classified in the non-TRD MDD control cohort. The non-MDD control cohort comprised patients without MDD. In the non-TRD MDD and non-MDD cohorts, the index date was imputed to mimic the distribution of time in the TRD cohort from the first antidepressant to the index date or from the start of eligibility to the index date, respectively. Patients with <6 months of continuous insurance eligibility pre-/post-index, psychosis, schizophrenia, bipolar disorder and related conditions, dementia, and development disorders, and/or no baseline anxiety disorder and/or SUD were excluded. Patients with TRD were matched 1:1 to patients with non-TRD MDD and patients without MDD, based on exact matching factors (i.e. availability of work loss data) and propensity scores computed based on characteristics measured pre-index. Outcomes, including healthcare resource use (HRU) and costs, work productivity loss and related costs measured per patient per year ≤24 months post-index were compared between matched TRD, non-TRD MDD and non-MDD cohorts.

RESULTS

A total of 3166 patients were identified in the TRD cohort and matched to non-TRD MDD and non-MDD cohorts. Among patients with TRD (mean age 39 years, 60.5% female), 87.3% had an anxiety disorder, 24.1% had SUD. The TRD cohort had higher HRU vs non-TRD MDD and non-MDD cohorts: 0.32 vs 0.20 and 0.14 inpatient admissions, 0.91 vs 0.73 and 0.58 emergency department visits, and 23.8 vs 16.8 and 11.6 outpatient visits, respectively (all p < .01). The TRD cohort had higher healthcare costs ($16,674) vs non-TRD MDD ($10,945) and non-MDD ($6493) cohorts (all p < .01). Among patients with work loss data (N = 310/cohort), patients with TRD had more work loss days (54) and higher work loss-related costs ($13,674) vs patients with non-TRD MDD (32 days; $7131) and without MDD (17 days; $4798; all p < .01).

CONCLUSIONS

In patients with an anxiety disorder and/or SUD, TRD was associated with higher HRU, healthcare costs, work loss days and work loss-related costs.

Clinical Features and Outcomes of 124 Italian Patients With Treatment Resistant Depression: A Real-World, Prospective Study

Introduction: Treatment-resistant depression (TRD) is a debilitating condition affecting 20-30% of patients with major depressive disorders (MDD). Currently, there is no established standard of care for TRD, and wide variation in the clinical approach for disease management has been documented. Real-world data could help describe TRD clinical features, disease burden, and treatment outcome and identify a potential unmet medical need. Methods: We analyzed the Italian data from a European, prospective, multicentric, observational cohort study of patients fulfilling TRD criteria by the European Medicine Agency, with moderate to severe major depressive episode, and starting a new antidepressant treatment according to routinary clinical practice. They were followed up for minimum 6 months. Treatments received throughout the study period, disease severity, health-related quality of life and functioning were prospectively recorded and analyzed. Results: The Italian subcohort included 124 TRD patients (30.2% of patients of the European cohort; mean age 53.2 [sd = 9.8], women: 82, 66.1%). At enrollement, the mean (SD) duration of MDD was 16 years (sd = 11.1) and the mean duration of the ongoing major depressive episode (MDE) was 97.5 weeks (sd = 143.5); low scores of quality of life and functioning were reported. The most frequently antidepressant classes started at baseline (data available for 98 subjects) were selective serotonin reuptake inhibitors (SSRI, 42 patients [42.9%]) and serotonin-norepinephrine reuptake inhibitors (SNRI, 32 patients [32.7%]). In terms of treatment strategies, 50 patients (51%) started augmentation therapies, 18 (18.4%) combination therapies and 24 (24.5%) monoterapies (6 patients [6%] started a non-antidepressant drug only). Fourteen patients (11.3%) were treated with a psychosocial approach, including psychotherapy. After 6 months of treatment, clinical assessments were collected for 89 patients: 64 (71.9%) showed no response, 9 (10.1%) response without remission and 16 (18.0%) were in remission; non-responder patients showed lower quality of life and higher disability scores than responder patients. Conclusions: In our sample of TRD patients, we documented substantial illness burden, low perceived quality of life and poor outcome, suggesting an unmet treatment need in TRD care in Italy. Registration Number: ClinicalTrials.gov, number: NCT03373253.