Network structure of time-varying depressive symptoms through dynamic time warp analysis in late-life depression.

OBJECTIVES: Late-life major depressive disorder (MDD) can be conceptualized as a complex dynamic system. However, it is not straightforward how to analyze the covarying depressive symptoms over time in case of sparse panel data. Dynamic time warping (DTW) analysis may yield symptom networks and dimensions both at the patient and group level. METHODS: In the Netherlands Study of Depression in Older People (NESDO) depressive symptoms were assessed every 6 months using the 30-item Inventory of Depressive Symptomatology (IDS) with up to 13 assessments per participant. Our sample consisted of 182 persons, aged ≥ 60 years, with an IDS total score of 26 or higher at baseline. Symptom networks dimensions, and centrality metrics were analyzed using DTW and Distatis analyses. RESULTS: The mean age was 69.8 years (SD 7.1), with 69.0% females, and a mean IDS score of 38.0 (SD = 8.7). DTW enabled visualization of an idiographic symptom network in a single NESDO participant. In the group-level nomothetic approach, four depressive symptom dimensions were identified: "core symptoms", "lethargy/somatic", "sleep", and "appetite/atypical". Items of the "internalizing symptoms" dimension had the highest centrality, whose symptom changes over time were most similar to those changes of other symptoms. CONCLUSIONS: DTW revealed symptom networks and dimensions based on the within-person symptom changes in older MDD patients. Its centrality metrics signal the most influential symptoms, which may aid personalized care.

Melancholia as Predictor of Electroconvulsive Therapy Outcome in Later Life.

OBJECTIVES: In clinical practice, particularly melancholic depression benefits from electroconvulsive therapy (ECT), albeit research melancholia criteria from the Diagnostic and Statistical Manual of Mental Disorders (DSM) is not conclusive. We compared clinical characteristics and ECT outcome of melancholic and nonmelancholic depression, here defined by psychomotor symptoms. METHODS: One hundred ten depressed older in-patients treated with ECT were included in the Mood Disorders in Elderly treated with ECT study. The CORE was used for the assessment of psychomotor symptoms, with a score of 8 or higher defining melancholic depression. Depression severity was measured before, during, and after ECT. Characteristics were compared across melancholic and nonmelancholic patients. Regression analysis was used to assess the relation between psychomotor symptoms and remission/response, and survival analysis was used to examine the difference in time. RESULTS: Patients with melancholic depression had higher severity, lower cognitive and overall functioning, and lower prevalence of cardiovascular disease. However, no significant relations were found between CORE scores and remission/response. Because psychotic symptoms are a positive predictor of ECT response and remission, we examined whether CORE score was a predictor of response in the nonpsychotic group (n = 49). In nonpsychotic patients, remission was 62%, and the association between CORE scores and remission almost reached significance (P = 0.057). DISCUSSION: Although melancholically and nonmelancholically depressed patients differed significantly on several clinical characteristics, ECT outcome did not differ. Analyses may be hampered by a high prevalence of psychotic features. In nonpsychotic patients, CORE scores neared significance as predictor of remission, suggesting that CORE scores might be a distinguishing characteristic of melancholia in nonpsychotic patients and a clinical useful predictor of ECT response.

Differences in Speed of Response of Depressive Symptom Dimensions in Older Persons During Electroconvulsive Therapy.

INTRODUCTION: Electroconvulsive therapy (ECT) is an important and effective treatment for depression. However, research on course trajectories of depressive symptoms during ECT is limited. Insight into putative differences in speed of response of depressive symptom dimensions may enable clinicians to optimally inform patients and their relatives. Therefore, we aim to examine course trajectories of depressive symptom dimensions in depressed older persons during ECT. METHODS: Data were derived from the Mood Disorders in Elderly treated with Electro Convulsive Therapy study, including 110 persons, aged 55 years or more, with a current diagnosis of major depressive disorder and referred for ECT. Exploratory factor analysis was used to identify symptom dimensions, using the 10 depression items of the Montgomery-Åsberg Depression Rating Scale (MADRS). Differences in course trajectories of symptom dimension during 2 weeks were examined by multilevel analyses. RESULTS: Three symptom dimensions were identified: a "mood," "melancholic," and "suicidal" dimension. Mood showed a significantly greater severity decline as compared with melancholic and suicidal at the 1-week follow-up. At the 2-week follow-up, both mood and melancholic demonstrated a significantly greater decline as compared with suicidal. However, because scores on the suicidality item of the Montgomery-Asberg Depression Rating Scale were already lower at baseline compared with the other items, a floor effect cannot be ruled out. DISCUSSION: All symptom dimensions of depression showed a rapid response to ECT. Our findings did not support the general assumption that suicidal symptoms may be the first to improve. However, a floor effect on the suicidality item cannot be ruled out.

Presupplementary motor area hyperactivity during response inhibition: a candidate endophenotype of obsessive-compulsive disorder.

OBJECTIVE: Endophenotype studies of obsessive-compulsive disorder (OCD) may uncover heritable traits that are related to genetic susceptibility to OCD. Deficient response inhibition is a promising endophenotype of OCD, although its functional neural correlates have not been extensively studied. The authors sought to determine the functional neural correlates of response inhibition in a large sample of medication-free OCD patients and their unaffected siblings. METHOD: Forty-one OCD patients, 17 of their siblings, and 37 matched healthy comparison subjects performed a stop-signal task during 3-T functional MRI. The stop-signal reaction time provided a behavioral measure of response inhibition. The neural correlates of response inhibition were assessed in a region-of-interest analysis that included the presupplementary motor area, inferior frontal gyrus, subthalamic nucleus, and inferior parietal cortex. RESULTS: Patients with OCD had greater stop-signal reaction times relative to healthy comparison subjects. The numerical stop-signal reaction time difference between siblings and comparison subjects failed to reach significance. Both patients with OCD and their siblings showed greater activity in the left presupplementary motor area during successful inhibition relative to comparison subjects. Relative to both the comparison subjects and the siblings, patients with OCD showed decreased activity in the right inferior parietal cortex and inferior frontal gyrus. In patients and siblings, presupplementary motor area activity correlated negatively with stop-signal reaction time. CONCLUSIONS: These findings suggest that presupplementary motor area hyperactivity is a neurocognitive endophenotype of OCD that is possibly related to inefficient neural processing within the presupplementary motor area itself. Patients with OCD further showed a state-dependent deficit in recruiting right inferior parietal cortex and inferior frontal gyrus, which may contribute to their inhibition deficit.