Differential clinical characteristics and possible predictors of bipolarity in a sample of unipolar and bipolar inpatients

Major affective conditions including both unipolar (UD) and bipolar disorders (BD) are associated with significant disability throughout the life course. We aimed to investigate the most relevant socio-demographic/clinical differences between UD and BD subjects. Our sample included 180 inpatients, of which 82 (45.5%) participants were diagnosed with UD and 98 (54.5%) with BD. Relative to UD patients, BD individuals were more likely to report prior psychoactive medications, lifetime psychotic symptoms, nicotine abuse, a reduced ability to provide to their needs, gambling behavior, and fewer nonsuicidal self-harm episodes. Moreover, BD patients were more likely to report severe side effects related to medications, a younger age at illness onset and first hospitalization, higher illness episodes, and longer illness duration in years than UD subjects. In a multivariate logistic analysis accounting for age, gender, and socio-demographic characteristics, a significant positive contribution to bipolarity was found only for higher lifetime psychotic symptoms (β = 1.178; p ≤ .05) and number of illness episodes (β = .155; p ≤ .05). The present findings suggest that specific clinical factors may be used in order to better distinguish between UD and BD subgroups. Further studies are required to replicate these findings in larger samples.

Depressive residual symptoms are associated with illness course characteristics in a sample of outpatients with bipolar disorder

Rates of 50-70% of residual symptoms referring to subsyndromal manifestations between episodes that do not meet the required criteria for episode definition were reported in bipolar disorder (BD). However, the specific role of these symptoms on the course of BD patients is poorly understood; thus, we aimed to investigate factors associated with depressive residual symptoms. Overall, 255 currently euthymic BD outpatients on maintenance treatment, including 95 (37.2%) males and 160 (62.8%) females, were consecutively recruited at the Section of Psychiatry, Department of Neuroscience, University of Genoa (Italy) and underwent detailed structured interviews, comprehensive clinical interviews, and clinical record reviews for assessment/collection of relevant information concerning the course of illness and clinical status including cross-referral of all available information. After categorizing subjects according to the presence/absence of residual symptoms, groups were compared along clinical variables and variables associated with residual symptoms were analyzed using multivariate analyses. Subjects with residual symptoms were less likely to report substance abuse (χ²₍₂₎ = 11.937, p ≤ 0.005) and lifetime psychotic symptoms (χ²₍₂₎ = 10.577, p = 0.005), and more likely to report higher illness episodes, longer duration of illness (t₂₅₃ = 67.282, p ≤ 0.001; t₂₅₃ = 10.755, p ≤ 0.001), and longer duration of current illness episode (t₂₅₃ = 7.707, p ≤ 0.001) than those without residual symptoms. After multivariate analyses, a significant positive contribution to residual symptoms was given only by duration of current illness episode (β = 0.003; p ≤ 0.05), and lifetime psychotic symptoms (β = 1.094; p ≤ 0.005). Clinicians have to pay attention to minimize residual symptoms that may significantly impact on the course of BD and achievement of full remission between episodes.