The longitudinal trajectory of emotional cognition in subgroups of recently diagnosed patients with bipolar disorder.

Although cross-sectional studies show heterogeneity in emotional cognition in bipolar disorder (BD), the temporal course within subgroups is unclear. In this prospective, longitudinal study we assessed the trajectories of emotional cognition subgroups within a 16-month follow-up period in recently diagnosed BD patients compared to healthy controls (HC). Recently diagnosed BD patients and HC underwent comprehensive emotional and non-emotional testing at baseline and again at follow-up. We employed hierarchical cluster analysis at baseline to identify homogenous emotional cognition subgroups of patients, and changes across the subgroups of BD and HC were assessed with linear mixed-model analyses. We found two emotional cognition subgroups: subgroup 1 (65%, n = 179), showing heightened negative emotional reactivity in neutral and negative social scenarios and faster recognition of emotional facial expressions than HC (ps<0.001, n = 190), and subgroup 2 (35%, n = 96) showing blunted reactivity in positive social scenarios, impaired emotion regulation, poorer recognition of positive and slower recognition of all facial expressions than HC (ps≤.03). Subgroup 1 exhibited normalization of the initial emotional cognition abnormalities in follow-up. In contrast, subgroup 2 showed a lack of improvement in reactivity positively-valenced emotional information. Patients in subgroup 2 presented more and longer mixed episodes during the follow-up time and were more often prescribed lithium. One third of patients display blunted emotional reactivity, impaired emotion regulation abilities and facial expression recognition difficulties also show persistent impairments and poorer course of illness. This subgroup may indicate a need for earlier and more targeted therapeutic interventions.

Brain-derived neurotrophic factor, impaired glucose metabolism, and bipolar disorder course.

OBJECTIVES: The neurotrophin brain-derived neurotrophic factor (BDNF) has been proposed as a potential biomarker in bipolar disorder (BD). However, current evidence is limited and results have been highly heterogeneous. This study aimed to assess the moderating effect of impaired glucose metabolism (IGM) on plasma levels of BDNF in individuals with BD, and on the relationship between BDNF and variables of illness course. METHODS: We measured and compared the plasma levels of BDNF in individuals with BD (n=57) and healthy controls (n=26). IGM was operationalized as pre-diabetes or type 2 diabetes mellitus. Information related to current and past psychiatric/medical history, as well as prescription of pharmacological treatments was also captured. RESULTS: Individuals with BD had lower levels of BDNF, relative to healthy controls, after adjustment for age, gender, current medications, smoking, alcohol use, and IGM (P=.046). There was no effect of IGM (P=.860) and no interaction between BD diagnosis and IGM (P=.893). Peripheral BDNF levels were positively correlated with lifetime depressive episodes (P<.001), psychiatric hospitalizations (P=.001) and suicide attempts (P=.021). IGM moderated the association between BDNF and the number of previous mood episodes (P<.001), wherein there was a positive correlation in euglycemic participants and a negative correlation in individuals with IGM. CONCLUSIONS: BD is independently associated with lower levels of BDNF; IGM may modify the relationship between BDNF and BD course, suggesting an interactive effect of BDNF with metabolic status on illness progression.