Data-driven atypical profiles of depressive symptoms: Identification and validation in a large cohort

Validation of a novel method of ultraviolet-induced cutaneous inflammation and its associations with anhedonia

Affective immunology of the skin is a growing area; however, established protocols for measuring individual differences in cutaneous inflammation are lacking. To address this, we present a preliminary validation of Precision Implementation of Minimal Erythema Dose (PI-MED) testing as a method for measuring cutaneous inflammation. PI-MED is a recently adapted protocol, optimized for reproducibility and individual differences research, that uses ultraviolet (UV) light to evoke cutaneous erythema, or inflammatory skin reddening. PI-MED's novel UV dosage schedule produces standardized erythema responses across different skin pigmentation types and shows strong internal consistency within person and good test-retest reliability across 8-10 weeks. In line with predictions, increased PI-MED erythema was associated with heightened anhedonia, across several measures, beyond influences of non-affective covariates. While future work should further refine the dosage schedule for the lightest and darkest skin types, overall, evidence supports PI-MED as a protocol for inducing and measuring individual differences in cutaneous inflammation. Further, PI-MED-induced erythema can expand psychoneuroimmunology research by offering a complementary assessment for general inflammatory tone. This work adds to a growing body of evidence demonstrating a distinct relationship between inflammation and anhedonia.

Individual and common patterns in the order of symptom improvement during outpatient treatment for major depression

BACKGROUND

Research so far provided few clues on the order in which depressive symptoms typically remit during treatment. This study examined which depressive symptoms improve first, and whether symptoms changed before, simultaneous with, or after the core symptoms of depression (i.e., sad mood, loss of pleasure, and loss of interest).

METHODS

Participants were 176 patients with Major Depressive Disorder (MDD) receiving outpatient treatment (a combination of pharmacotherapy and psychological interventions) for depression. Participants filled out the Inventory of Depressive Symptomatology - Self Report (IDS-SR) for 16 to 20 consecutive weeks. For each symptom, the timing of onset of a persistent improvement was determined for each single-subject separately.

RESULTS

Which symptoms improved first differed markedly across patients. The core depression symptoms improved 1.5 to 2 times more often before (48% - 60%) than after (19% -28%) depressive cognitions ('view of myself' and 'view of the future'), anxiety symptoms ('feeling irritable' and 'feeling anxious / tense') and vegetative symptoms ('loss of energy', 'slowed down', and 'physical energy'). Only improvements in suicidal thoughts were more likely to occur before (46% - 48%) than after (29%) improvements in the depression core symptoms.

LIMITATIONS

Not all 'core depression-non-core symptom' combinations could be tested because some symptoms did not improve in a sufficient number of patients.

CONCLUSIONS

Which improvements mark the start of symptom remission differed between patients. Improvements in the core depression symptoms 'sad mood', 'loss of interest', and 'loss of pleasure' were more likely to occur before than after improvements in non-core symptoms.

The Assessment and Impact of Careless Responding in Routine Outcome Monitoring within Mental Health Care

Careless responding by mental health patients on self-report assessments is rarely investigated in routine care despite the potential for serious consequences such as faulty clinical decisions. We investigated validity indices most appropriate for detecting careless responding in routine outcome monitoring (ROM) in mental health-care. First, we reviewed indices proposed in previous research for their suitability in ROM. Next, we evaluated six selected indices using data of the Brief Symptom Inventory and the Mood and Anxiety Symptom Questionnaire from 3,483 outpatients. Simulations showed that for typical ROM scales the Lmax index, Mahalanobis distance, and inter-item standard deviation may be too strongly confounded with the latent trait value to compare careless responding across patients with different symptom severity. Application of two different classification methods to the validity indices did not converge in similar prevalence estimates of careless responding. Finally, results suggest that careless responding does not have a substantial biasing effect on scale-score statistics. We recommend the lzp person-fit index to screen for random careless responding in large ROM data sets. However, additional research should further investigate methods for detecting repetitive responding in typical ROM data and assess whether there are specific circumstances in which simpler validity statistics or direct screening methods perform similarly as the lzp index.

Severity, course trajectory, and within-person variability of individual symptoms in patients with major depressive disorder

BACKGROUND

Depression shows a large heterogeneity of symptoms between and within persons over time. However, most outcome studies have assessed depression as a single underlying latent construct, using the sum score on psychometric scales as an indicator for severity. This study assesses longitudinal symptom-specific trajectories and within-person variability of major depressive disorder over a 9-year period.

METHODS

Data were derived from the Netherlands Study of Depression and Anxiety (NESDA). This study included 783 participants with a current major depressive disorder at baseline. The Inventory Depressive Symptomatology-Self-Report (IDS-SR) was used to analyze 28 depressive symptoms at up to six time points during the 9-year follow-up.

RESULTS

The highest baseline severity scores were found for the items regarding energy and mood states. The core symptoms depressed mood and anhedonia had the most favorable course, whereas sleeping problems and (psycho-)somatic symptoms were more persistent over 9-year follow-up. Within-person variability was highest for symptoms related to energy and lowest for suicidal ideation.

CONCLUSIONS

The severity, course, and within-person variability differed markedly between depressive symptoms. Our findings strengthen the idea that employing a symptom-focused approach in both clinical care and research is of value.

Development and external validation of a prediction rule for an unfavorable course of late-life depression: A multicenter cohort study

BACKGROUND

Given the poor prognosis of late-life depression, it is crucial to identify those at risk. Our objective was to construct and validate a prediction rule for an unfavourable course of late-life depression.

METHODS

For development and internal validation of the model, we used The Netherlands Study of Depression in Older Persons (NESDO) data. We included participants with a major depressive disorder (MDD) at baseline (n = 270; 60-90 years), assessed with the Composite International Diagnostic Interview (CIDI). For external validation of the model, we used The Netherlands Study of Depression and Anxiety (NESDA) data (n = 197; 50-66 years). The outcome was MDD after 2 years of follow-up, assessed with the CIDI. Candidate predictors concerned sociodemographics, psychopathology, physical symptoms, medication, psychological determinants, and healthcare setting. Model performance was assessed by calculating calibration and discrimination.

RESULTS

111 subjects (41.1%) had MDD after 2 years of follow-up. Independent predictors of MDD after 2 years were (older) age, (early) onset of depression, severity of depression, anxiety symptoms, comorbid anxiety disorder, fatigue, and loneliness. The final model showed good calibration and reasonable discrimination (AUC of 0.75; 0.70 after external validation). The strongest individual predictor was severity of depression (AUC of 0.69; 0.68 after external validation).

LIMITATIONS

The model was developed and validated in The Netherlands, which could affect the cross-country generalizability.

CONCLUSIONS

Based on rather simple clinical indicators, it is possible to predict the 2-year course of MDD. The prediction rule can be used for monitoring MDD patients and identifying those at risk of an unfavourable outcome.

Person-fit feedback on inconsistent symptom reports in clinical depression care

BACKGROUND

Depressive patients can present with complex and different symptom patterns in clinical care. Of these, some may report patterns that are inconsistent with typical patterns of depressive symptoms. This study aimed to evaluate the validity of person-fit statistics to identify inconsistent symptom reports and to assess the clinical usefulness of providing clinicians with person-fit score feedback during depression assessment.

METHODS

Inconsistent symptom reports on the Inventory of Depressive Symptomatology Self-Report (IDS-SR) were investigated quantitatively with person-fit statistics for both intake and follow-up measurements in the Groningen University Center of Psychiatry (n = 2036). Subsequently, to investigate the causes and clinical usefulness of on-the-fly person-fit alerts, qualitative follow-up assessments were conducted with three psychiatrists about 20 of their patients that were randomly selected.

RESULTS

Inconsistent symptom reports at intake (12.3%) were predominantly characterized by reporting of severe symptoms (e.g. psychomotor slowing) without mild symptoms (e.g. irritability). Person-fit scores at intake and follow-up were positively correlated (r = 0.45). Qualitative interviews with psychiatrists resulted in an explanation for the inconsistent response behavior (e.g. complex comorbidity, somatic complaints, and neurological abnormalities) for 19 of 20 patients. Psychiatrists indicated that if provided directly after the assessment, a person-fit alert would have led to new insights in 60%, and be reason for discussion with the patient in 75% of the cases.

CONCLUSIONS

Providing clinicians with automated feedback when inconsistent symptom reports occur is informative and can be used to support clinical decision-making.

Person misfit on the Inventory of Depressive Symptomatology: Low quality self-report or true atypical symptom profile?

Person misfit on a self-report measure refers to a response pattern that is unlikely given a theoretical measurement model. Person misfit may reflect low quality self-report data, for example due to random responding or misunderstanding of items. However, recent research in the context of psychopathology suggests that person misfit may reflect atypical symptom profiles that have implications for diagnosis or treatment. We followed-up on Wanders et al. (Journal of Affective Disorders, 180, 36-43, 2015) who investigated person misfit on the Inventory of Depressive Symptomatology (IDS) in the Netherlands Study of Depression and Anxiety (n = 2,981). Our goal was to investigate the extent to which misfit on the IDS reflects low-quality self-report patterns and the extent to which it reflects true atypical symptom profiles. Regression analysis showed that person misfit related more strongly to self-report quality indicators than to variables quantifying theoretically-derived atypical symptom profiles. A data-driven atypical symptom profile explained most variance in person misfit, suggesting that person misfit on the IDS mainly reflects a sample- and questionnaire-specific atypical symptom profile. We concluded that person-fit statistics are useful for detecting IDS scores that may not be valid. Further research is necessary to support the interpretation of person misfit as reflecting a meaningful atypical symptom combination.

Promoting Physical Activity through Priming the Content of Motivation

Non-conscious processes are important in influencing the performance of a number of behaviors, such as physical activity. One way that such processes can be influenced is through priming. Despite this, approaches within health psychology have predominantly focused on reflective processes with a number of psychological theories dedicated to identifying the predictors of intention. In doing so, critical beliefs and thoughts are first identified and then altered within interventions. Such work has shown limited effectiveness, however, with a gap apparent between what one intends to do and what subsequently ensues. Although there have been attempts to bridge this gap, such as theoretical integration, recent efforts include priming implicit processes. The aim of this commentary is to demonstrate the potential effectiveness of priming non-conscious processes and to suggest that the content of motivation should also succumb to priming influences. This brief review suggests that priming one of the most influential conscious processes, that of self-efficacy, could demonstrate particular effectiveness in promoting physical activity. Thus, the main purpose of the article is to suggest that the content of implicit processes as well their more traditional conscious counterparts may provide useful intervention targets. To achieve this, the article will first introduce the role of non-conscious processes and behavioral priming. Following this, the more common reflective processes will be outlined as well as attempts at theoretical integration. Finally, the article will identify studies priming non-conscious processes and will then suggest priming self-efficacy.

Satisficing in Mental Health Care Patients: The Effect of Cognitive Symptoms on Self-Report Data Quality

Respondents may use satisficing (i.e., nonoptimal) strategies when responding to self-report questionnaires. These satisficing strategies become more likely with decreasing motivation and/or cognitive ability (Krosnick, 1991). Considering that cognitive deficits are characteristic of depressive and anxiety disorders, depressed and anxious patients may be prone to satisficing. Using data from the Netherland’s Study of Depression and Anxiety (N = 2,945), we studied the relationship between depression and anxiety, cognitive symptoms, and satisficing strategies on the NEO Five-Factor Inventory. Results showed that respondents with either an anxiety disorder or a comorbid anxiety and depression disorder used satisficing strategies substantially more often than healthy respondents. Cognitive symptom severity partly mediated the effect of anxiety disorder and comorbid anxiety disorder on satisficing. The results suggest that depressed and anxious patients produce relatively low-quality self-report data—partly due to cognitive symptoms. Future research should investigate the degree of satisficing across different mental health care assessment contexts.

Implicit Processes, Self-Regulation, and Interventions for Behavior Change

The ability to regulate and subsequently change behavior is influenced by both reflective and implicit processes. Traditional theories have focused on conscious processes by highlighting the beliefs and intentions that influence decision making. However, their success in changing behavior has been modest with a gap between intention and behavior apparent. Dual-process models have been recently applied to health psychology; with numerous models incorporating implicit processes that influence behavior as well as the more common conscious processes. Such implicit processes are theorized to govern behavior non-consciously. The article provides a commentary on motivational and volitional processes and how interventions have combined to attempt an increase in positive health behaviors. Following this, non-conscious processes are discussed in terms of their theoretical underpinning. The article will then highlight how these processes have been measured and will then discuss the different ways that the non-conscious and conscious may interact. The development of interventions manipulating both processes may well prove crucial in successfully altering behavior.

Response Inconsistency of Patient-Reported Symptoms as a Predictor of Discrepancy Between Patient and Clinician-Reported Depression Severity

The aim of this study was to assess the extent to which discrepancy between self-reported and clinician-rated severity of depression are due to inconsistent self-reports. Response inconsistency threatens the validity of the test score. We used data from a large sample of outpatients ( N = 5,959) who completed the self-report Beck Depression Inventory-II (BDI-II) and the clinician-rated Montgomery-Åsberg Depression Rating Scale (MADRS). We used item response theory based person-fit analysis to quantify the inconsistency of the self-report item scores. Inconsistency was weakly positively related to patient-clinician discrepancy (i.e., higher BDI-II scores relative to MADRS scores). The mediating effect of response inconsistency in the relationship between discrepancy and demographic (e.g., ethnic origin) and clinical variables (e.g., cognitive problems) was negligible. The small direct and mediating effects of response inconsistency suggest that inaccurate patient self-reports are not a major cause of patient-clinician discrepancy in outpatient samples. Future research should investigate the role of clinician biases in explaining clinician-patient discrepancy.

The Relationship Between Sleep Disturbances and Psychiatric Disorders: Introduction and Overview

Changes in the psychiatric diagnostic guidelines with the transition from Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV to DSM-V include acknowledgment that primary sleep disorders such as insomnia can occur in conjunction with medical and psychiatric disorders. This change in viewpoint regarding the definition of primary sleep disorders opens the way to the recognition that patients with psychiatric disorders demonstrate a high prevalence of sleep disturbances, with complaints of insomnia and excessive daytime sleepiness being especially commonly reported. Recent investigations have pointed to a bidirectional relationship between sleep disturbances and psychiatric disorders.