The Use of Intensive Longitudinal Methods in Research on Suicidal Thoughts and Behaviors: A Systematic Review

Psychological mechanisms of the development of suicidal ideation: Longitudinal cohort study

INTRODUCTION

This study aimed to investigate the mechanisms of the development of suicidal ideation and its moderating and protective factors. Drawing on the Interpersonal-psychological theory of suicide, we proposed that disruptions to belongingness, in conjunction with tolerance of health risk, may influence the development of suicidal ideation above and beyond psychosocial changes such as disruptions to finances and work.

METHODS

The study involved a longitudinal investigation of an Australian representative sample reporting suicidal ideation fortnightly for 12 weeks between March and June 2020.

RESULTS

The results indicated that participants who reported higher levels of belongingness, mastery, and intolerance of health risk were less likely to experience suicidal ideation and had lower severity of suicidal ideation. Mastery significantly strengthened the negative link between belongingness and the incidence of suicidal ideation, while agreeableness significantly strengthened the negative link between belongingness and the severity of suicidal ideation over time.

CONCLUSION

The findings suggest that supporting effective social connectedness during times of isolation and promoting self-efficacy, mastery, and regulation of risk tolerance, may be crucial for suicide prevention and therapeutic intervention.

Prospective Relations between Life Stress, Emotional Clarity, and Suicidal Ideation in an Adolescent Clinical Sample

OBJECTIVE

Although life stress has been linked to adolescent suicidal ideation, most past research has been cross-sectional, and potential processes characterizing this relation remain unclear. One possibility may be a lack of emotional clarity. Informed by stress generation, the current study examined prospective relations between episodic life stress, lack of emotional clarity, and suicidal ideation in an adolescent clinical sample.

METHODS

The sample consisted of 180 youths (Mage = 14.89; SD = 1.35; 71.7% female; 78.9% White; 43.0% sexual minority) recruited from a psychiatric inpatient facility. Suicidal ideation severity was assessed at baseline and 18-month follow-up. Lack of emotional clarity and life stress were assessed at baseline, as well as 6-, and 12-month follow-ups. Two random-intercepts cross-lagged panel models were created to estimate within-person relations for variables of interest.

RESULTS

At the within-person level, lack of emotional clarity at baseline predicted greater 6-month impact of interpersonal dependent stressors (b = 0.29, p = .012, 95% CI [0.07, 0.52]), which subsequently predicted a greater 12-month lack of emotional clarity (b = 0.41, p = .005, 95% CI [0.12, 0.70]). Next, a 12-month lack of emotional clarity but not interpersonal dependent stress, predicted greater 18-month suicidal ideation (b = 0.81, p = .006, 95% CI [0.23, 1.30]; R2 = .24, p < .001). No significant relations were found for the lack of emotional clarity and independent stress.

CONCLUSIONS

Results support the stress generation hypothesis and suggest that future research should be conducted evaluating whether bolstering youth's understanding of their emotional experiences may reduce subsequent suicidal ideation.

Dynamic bidirectional relation between state mindfulness and suicidal ideation among female college students: The moderating effect of trait mindfulness

Research has indicated that mindfulness is a protective factor against suicidal ideation. However, the dynamic reciprocal relation between them has been understudied. In this study, 110 female college students with suicidal ideation completed a measure of trait mindfulness and a 28-day diary of suicidal ideation and three-dimensional state mindfulness, including acting with awareness, present-moment attention, and nonjudgmental acceptance. Dynamic structural equation modeling was used to examine the dynamic and bidirectional effects between dimensions of state mindfulness and suicidal ideation and the moderating effect of trait mindfulness. Results showed that suicidal ideation predicted lower levels of present-moment attention the next day. More importantly, there was a dynamic and bidirectional relation between nonjudgmental acceptance and suicidal ideation for people with trait mindfulness higher than the average level (i.e., M + 0.15SD). Our findings suggested that studies and interventions on suicide should pay more attention to specific dimensions of state mindfulness and trait mindfulness.

Daily Levels and Dynamic Metrics of Affective-Cognitive Constructs Associate With Suicidal Thoughts and Behaviours in Adults After Psychiatric Hospitalization

The period after psychiatric hospitalization is an extraordinarily high-risk period for suicidal thoughts and behaviours (STBs). Affective-cognitive constructs (ACCs) are salient risk factors for STBs, and intensive longitudinal metrics of these constructs may improve personalized risk detection and intervention. However, limited research has examined how within-person daily levels and between-person dynamic metrics of ACCs relate to STBs after hospital discharge. Adult psychiatric inpatients (N = 95) completed a 65-day ecological momentary assessment protocol after discharge as part of a 6-month follow-up period. Using dynamic structural equation models, we examined both within-person daily levels and between-person dynamic metrics (intensity, variability and inertia) of positive and negative affect, rumination, distress intolerance and emotion dysregulation as risk factors for STBs. Within-person lower daily levels of positive affect and higher daily levels of negative affect, rumination, distress intolerance and emotion dysregulation were risk factors for next-day suicidal ideation (SI). Same-day within-person higher rumination and negative affect were also risk factors for same-day SI. At the between-person level, higher overall positive affect was protective against active SI and suicidal behaviour over the 6-month follow-up, while greater variability of rumination and distress intolerance increased risk for active SI, suicidal behaviour and suicide attempt. The present study provides the most comprehensive examination to date of intensive longitudinal metrics of ACCs as risk factors for STBs. Results support the continued use of intensive longitudinal methods to improve STB risk detection. Interventions focusing on rumination and distress intolerance may specifically help to prevent suicidal crises during critical transitions in care.

Facets of social problem-solving as moderators of the real-time relation between social rejection and negative affect in an at-risk sample

Social rejection predicts negative affect, and theoretical work suggests that problem-solving deficits strengthen this relation in real-time. Nevertheless, few studies have explicitly tested this relation, particularly in samples at risk for suicide. This may be particularly important as social rejection and negative affect are significant predictors of suicide. The aim of the current study was to examine whether cognitive (i.e., perceiving problems as threats) and behavioral (i.e., avoidance) facets of problem-solving deficits moderated the real-time relation between social rejection and negative affect. The sample consisted of 49 young adults with past-month suicidal ideation. Demographic information, social problem-solving deficits, as well as depressive/anxiety symptoms and stress levels were assessed at baseline. Social rejection and negative affect were assessed using ecological momentary assessment over the following 28 days. Dynamic structural equation modeling was used to assess relations among study variables. After accounting for depressive/anxiety symptoms, stress levels, sex, and age, only avoidance of problems bolstered the real-time positive relation between social rejection severity and negative affect (b = 0.04, 95% credibility interval [0.003, 0.072]). Individuals with suicidal ideation who possess an avoidant problem-solving style may be particularly likely to experience heightened negative affect following social rejection and may benefit from instruction in problem-solving skills.

Using machine learning with intensive longitudinal data to predict depression and suicidal ideation among medical interns over time

BACKGROUND

Use of intensive longitudinal methods (e.g. ecological momentary assessment, passive sensing) and machine learning (ML) models to predict risk for depression and suicide has increased in recent years. However, these studies often vary considerably in length, ML methods used, and sources of data. The present study examined predictive accuracy for depression and suicidal ideation (SI) as a function of time, comparing different combinations of ML methods and data sources.

METHODS

Participants were 2459 first-year training physicians (55.1% female; 52.5% White) who were provided with Fitbit wearable devices and assessed daily for mood. Linear [elastic net regression (ENR)] and non-linear (random forest) ML algorithms were used to predict depression and SI at the first-quarter follow-up assessment, using two sets of variables (daily mood features only, daily mood features + passive-sensing features). To assess accuracy over time, models were estimated iteratively for each of the first 92 days of internship, using data available up to that point in time.

RESULTS

ENRs using only the daily mood features generally had the best accuracy for predicting mental health outcomes, and predictive accuracy within 1 standard error of the full 92 day models was attained by weeks 7-8. Depression at 92 days could be predicted accurately (area under the curve >0.70) after only 14 days of data collection.

CONCLUSIONS

Simpler ML methods may outperform more complex methods until passive-sensing features become better specified. For intensive longitudinal studies, there may be limited predictive value in collecting data for more than 2 months.

Characteristics of Suicidal Ideation: A Systematic Review

BACKGROUND

The exploration of inter- and intra-individual variability in suicidal ideation (SI) is vital to suicide research. However, this research relies on the identification and measurement of standardized SI characteristics.

OBJECTIVE

This review aimed to identify characteristics of SI examined in research, describe how these characteristics are measured, and assess how they are aligned with those included in the Columbia Suicide Severity Rating Scale (C-SSRS).

METHODS

Four databases were systematically searched, and relevant data was extracted. The C-SSRS provided a framework for comparing SI names, measures and operational definitions.

RESULTS

After comparing operational definitions of identified characteristics, five core domains emerged: (1) severity, (2) temporality, (3) variability, (4) controllability, and (5) deterrents/reasons for ideating. Except for variability, all SI characteristics in the literature were congruent with those measured in the C-SSRS.

CONCLUSIONS

This review highlighted conceptual and methodologic inconsistencies in the study of SI, specifically the nomenclature, measurement and definitions of SI characteristics. Standardized approaches to the study of SI characteristics are needed. These approaches will enhance accurate and reliable measurement of SI, allow for findings to be synthesized across studies and propel the exploration of inter and intra-individual SI variability leading to more individualized and effective SI treatment.

Utilizing daily mood diaries and wearable sensor data to predict depression and suicidal ideation among medical interns

BACKGROUND

Intensive longitudinal methods (ILMs) for collecting self-report (e.g., daily diaries, ecological momentary assessment) and passive data from smartphones and wearable sensors provide promising avenues for improved prediction of depression and suicidal ideation (SI). However, few studies have utilized ILMs to predict outcomes for at-risk, non-clinical populations in real-world settings.

METHODS

Medical interns (N = 2881; 57 % female; 58 % White) were recruited from over 300 US residency programs. Interns completed a pre-internship assessment of depression, were given Fitbit wearable devices, and provided daily mood ratings (scale: 1-10) via mobile application during the study period. Three-step hierarchical logistic regressions were used to predict depression and SI at the end of the first quarter utilizing pre-internship predictors in step 1, Fitbit sleep/step features in step 2, and daily diary mood features in step 3.

RESULTS

Passively collected Fitbit features related to sleep and steps had negligible predictive validity for depression, and no incremental predictive validity for SI. However, mean-level and variability in mood scores derived from daily diaries were significant independent predictors of depression and SI, and significantly improved model accuracy.

LIMITATIONS

Work schedules for interns may result in sleep and activity patterns that differ from typical associations with depression or SI. The SI measure did not capture intent or severity.

CONCLUSIONS

Mobile self-reporting of daily mood improved the prediction of depression and SI during a meaningful at-risk period under naturalistic conditions. Additional research is needed to guide the development of adaptive interventions among vulnerable populations.

A meta-analysis on the affect regulation function of real-time self-injurious thoughts and behaviours

Prominent theories suggest that self-injurious thoughts and behaviours are negatively reinforced by decreased negative affect. The present meta-analysis quantifies effects from intensive longitudinal studies measuring negative affect and self-injurious thoughts and behaviours. We obtained data from 38 of the 79 studies (48%, 22 unique datasets) involving N = 1,644 participants (80% female, 75% white). Individual-participant data meta-analyses revealed changes in affect pre/post self-injurious thoughts and behaviours. In antecedent models, results supported increased negative affect before nonsuicidal self-injurious behaviour (k = 14, 95% CI 0.09 to 0.31) and suicidal thoughts (k = 14, 95% CI 0.03 to 0.19). For consequence models, negative affect was reduced following nonsuicidal self-injurious thoughts (k = 6, 95% CI -0.79 to -0.44), nonsuicidal self-injurious behaviours (k = 14, 95% CI -0.73 to -0.19) and suicidal thoughts (k = 13, 95% CI -0.79 to -0.23). Findings, which were not moderated by sampling strategies or sample composition, support the affect regulation function of self-injurious thoughts and behaviours.

The importance of recognizing worthlessness for suicide prevention in adolescents with Attention-deficit/hyperactivity disorder

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common psychiatric diagnoses among children and adolescents. Depression and general anxiety disorder (GAD) are often co-occurring with ADHD among children and adolescents. Previous studies have found that ADHD, depression and GAD are all strongly correlated with suicidal thoughts and planning.

AIM

The current study aimed to further explore the association between ADHD, GAD and depressive symptoms as well as their association with suicidal thoughts and planning among adolescents.

METHOD

Adolescents with ADHD diagnosis were involved from child psychiatry outpatient clinics and adolescents without a psychiatric treatment or diagnosis were enrolled from high schools in Hungary. The Mini International Neuropsychiatric Interview for Children and Adolescents was used to evaluate psychiatric symptoms and disorders as well as suicidal thoughts and planning. Regularized psychological networks were used to investigate the associations.

RESULTS

Altogether 185 adolescents (58 females and 127 males; mean age 14.79 years, SD = 1.48), 89 with ADHD and 96 without ADHD were enrolled. Depression symptom worthlessness was directly related to suicidal thoughts and planning, CI95 of the logit B between worthlessness and suicidal thought (0.72, 1.66). Both ADHD and anxiety were indirectly related to suicidal thoughts and planning through depression: CI95 of the logit B between being disorganized and feeling worthless is (0.38, 3.02), and CI95 of the logit B between being distressed and feeling worthless is (0.57, 2.52).

CONCLUSIONS

This study draws the attention of clinicians to the importance of recognizing "worthlessness" for suicide prevention in adolescents with ADHD. Furthermore, the results support previous studies, whereby symptoms of depression and anxiety mediate the relationship between ADHD and suicidal thoughts and planning. These results highlight the importance of ADHD comorbidities with depression and GAD and their effect on suicidal thoughts and planning.

Just-in-Time Adaptive Interventions for Suicide Prevention: Promise, Challenges, and Future Directions

The suicide rate (currently 14 per 100,000) has barely changed in the United States over the past 100 years. There is a need for new ways of preventing suicide. Further, research has revealed that suicidal thoughts and behaviors and the factors that drive them are dynamic, heterogeneous, and interactive. Most existing interventions for suicidal thoughts and behaviors are infrequent, not accessible when most needed, and not systematically tailored to the person using their own data (e.g., from their own smartphone). Advances in technology offer an opportunity to develop new interventions that may better match the dynamic, heterogeneous, and interactive nature of suicidal thoughts and behaviors. Just-In-Time Adaptive Interventions (JITAIs), which use smartphones and wearables, are designed to provide the right type of support at the right time by adapting to changes in internal states and external contexts, offering a promising pathway toward more effective suicide prevention. In this review, we highlight the potential of JITAIs for suicide prevention, challenges ahead (e.g., measurement, ethics), and possible solutions to these challenges.