A transdiagnostic approach to negative symptoms: exploring factor structure and negative symptoms in bipolar disorders.

Background: Negative symptoms are increasingly recognized as transdiagnostic phenomena, linked to reduced quality of life and functioning, and often caused or worsened by amendable external factors such as depression, social deprivation, side-effects of antipsychotics or substance use. The structure of negative symptoms fits into two dimensions: diminished expression and apathy. These may differ in association with external factors that influence their severity and may thus require different treatment approaches.

Turning the Spotlight on Apathy: Identification and Treatment in Schizophrenia Spectrum Disorders.

Among negative symptoms, apathy is central to the impairments in real-life functioning in schizophrenia spectrum disorders (SSD). Thus, optimizing treatment for apathy appears key to improve outcomes. In treatment research, however, negative symptoms are typically studied as a unifactorial construct.

The trajectory of two negative symptom dimensions in first-episode psychosis and the role of cannabis use: A 10-year follow-up study.

Objective: To investigate the trajectories of diminished expression and apathy over 10 years. Further, to explore the effects of baseline- and persistent cannabis use on the development of diminished expression and apathy during follow-up, while controlling other potential sources and predictors of secondary negative symptoms.

Methods: 351 participants with a first episode of non-affective psychosis were examined at baseline and invited to follow-up at one year and 10 years.

Exploring the relationship between recency and frequency of cannabis use and diminished expression and apathy as two dimensions of negative symptoms in first episode psychosis. A one-year follow-up study.

The association between cannabis use and negative symptoms remains unclear because of inconsistent results in existing studies. In this study we aimed to investigate the association between different aspects of cannabis use and 1) diminished expression and 2) apathy as a two-dimensional model of negative symptoms in a sample of 460 participants with first-episode psychosis. Data were collected on relevant clinical and demographic factors including diagnostics and habits of drug use at baseline, with a follow-up assessment after 12-months.

Misperception of sleep in bipolar disorder: an exploratory study using questionnaire versus actigraphy.

Background: The concept of misperception of sleep refers to the estimated discrepancy between subjective and objective measures of sleep. This has been assessed only in a few prior studies in individuals with Bipolar Disorder (BD) as compared to Healthy Controls (HC) and with mixed results.

Methods: We assessed a sample of 133 euthymic individuals with BD and 63 HC for retrospective subjective (Pittsburgh Sleep Quality Index) and objective (21 days of actigraphy recording) measures of total sleep time, sleep latency and sleep efficiency.

Trajectory and early predictors of apathy development in first-episode psychosis and healthy controls: a 10-year follow-up study.

Apathy is prevalent in first-episode psychosis (FEP) and associated with reduced global functioning. Investigations of the trajectory of apathy and its early predictors are needed to develop new treatment interventions. We here measured the levels of apathy over the first 10 years of treatment in FEP and in healthy controls (HC).