Clinical correlates of Cognitive Impairment in elderly patients with Bipolar Spectrum Disorders

Background: Increased risk of mild cognitive impairment (MCI) and dementia has been observed in Older Age Bipolar Disorder (OABD). However, the factors driving this association are not yet well studied. Considering that this population represents more than 25% of all patients with bipolar disorder (BD), the shortage of information in this area deserves to be addressed. Aim of the study: The aim of this study is to outline the clinical features associated with the development of MCI and/or dementia in elderly patients (over 50 years old) with bipolar spectrum disorder. Materials and Methods: 152 patients aged 50 years or older and diagnosed with bipolar spectrum disorders based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) criteria were included in the study and were subdivided into two subgroups based on the presence/absence of cognitive impairment. Subsequently, a subdivision into three subgroups according to the absence of cognitive impairment and the presence of MCI or dementia was made. Univariate comparisons were performed to assess the associations between clinical variables and cognitive impairment. Results: Cognitively impaired patients with BD had a higher prevalence of otherwise- specified BD than BD type 2 compared to cognitively unimpaired patients. Moreover, a later onset of the first affective episode of any polarity and a higher prevalence of dyslipidemia and vascular leukoencephalopathy were observed in cognitively impaired versus cognitively unimpaired participants. Current symptom severity and functional impairments measured by Clinical Global Impression (CGI), Global Assessment of Functioning (GAF) and Brief Psychiatric Rating Scale (BPRS) scores were more severe in patients with cognitive impairment, with an increasing trend from MCI to dementia. Conclusion: This study suggests that atypical features, late onset and metabolic comorbidity may predict the development of MCI and dementia in patients with OABD. As expected, the severity of symptoms is more pronounced in patients with comorbid cognitive impairment and BD.