Relationship Between Cognitive Function and Clinical Features in Patients With Bipolar I Disorder

Pathophysiological relationships between cognitive deficit in bipolar affective disorder and metabolic syndrome

INTRODUCTION AND OBJECTIVES

Bipolar disorder (BD) has been related to various cognitive dysfunctions as well as to a high prevalence of metabolic syndrome (MS), which seems to influence the cognitive performance of patients with BD. Therefore, different hypotheses have been generated to try to explain the pathophysiological relationship between cognitive deficit in BD and MS. The objective was to review the current literature regarding the possible pathophysiological explanation of the relationship between BD and MS and its effect on cognitive performance of patients with BD.

METHODS

A bibliographic search was carried out using MEDLINE, ClinicalKey, EMBASE, Literatura Latino-Americana y del Caribe en Ciencias de la Salud [Latin American and Caribbean Literature in Health Sciences] (LILACS), APA PsycNet, Scopus and Scielo databases, and the Pan-American Medical Electronic Library; using the following search terms: "bipolar disorder"[MeSH Terms] OR "bipolar disorder"[All Fields] OR "mood disorders"[All Fields] AND "cognitive deficit"[MeSH Terms] OR "cognitive deficit"[All Fields] OR "cognitive dysfunction"[All Fields] OR "cognitive impairment"[All Fields] OR "cognitive decline"[All Fields] AND "metabolic syndrome" [MeSH Terms] OR "metabolic abnormalities"[All Fields] OR "metabolic effects"[All Fields] OR "obesity" [All Fields] OR "abdominal obesity" [All Fields] OR "overweight" [All Fields] OR "diabetes" [All Fields] OR "hypertension" [All Fields] AND "antipsychotics" [MeSH Terms] OR "antipsychotics"[All Fields] AND "antidepressants" [MeSH Terms] OR "antidepressants"[All Fields] AND "mood stabilizers" [MeSH Terms] OR "mood stabilizers"[All Fields]. Filters: free full text, full text, from 2001 to 2022. A total of 80 articles in Spanish and English, of any type of design, were selected. Selection and reading were carried out by all the authors.

RESULTS AND CONCLUSIONS

The various pathophysiological hypotheses proposed, inflammatory, endocrine, drug, environmental and social, suggest that a series of changes at the macro and microcellular level are correlated in patients with BD and MS with a negative effect on cognition of patients both globally and in specific domains, mainly executive function, memory, attention, and perceptual motor skills. Research processes should be continued to explore the various hypotheses that support the relationship between BD, MS and cognition.

Using Chronobiological Phenotypes to Address Heterogeneity in Bipolar Disorder

Bipolar disorder (BD) is a neuropsychiatric mood disorder characterized by recurrent episodes of mania and depression in addition to disruptions in sleep, energy, appetite, and cognitive functions-rhythmic behaviors that typically change on daily cycles. BD symptoms can also be provoked by seasonal changes, sleep, and/or circadian disruption, indicating that chronobiological factors linked to the circadian clock may be a common feature in the disorder. Research indicates that BD exists on a clinical spectrum, with distinct subtypes often intersecting with other psychiatric disorders. This heterogeneity has been a major challenge to BD research and contributes to problems in diagnostic stability and treatment outcomes. To address this heterogeneity, we propose that chronobiologically related biomarkers could be useful in classifying BD into objectively measurable phenotypes to establish better diagnoses, inform treatments, and perhaps lead to better clinical outcomes. Presently, we review the biological basis of circadian time keeping in humans, discuss the links of BD to the circadian clock, and pre-sent recent studies that evaluated chronobiological measures as a basis for establishing BD phenotypes. We conclude that chronobiology may inform future research using other novel techniques such as genomics, cell biology, and advanced behavioral analyses to establish new and more biologically based BD phenotypes.