Sleep characteristics and cognitive impairment in bipolar disorder: age-specific associations

Bipolar disorder (BD) is a chronic condition often associated with sleep disturbances and cognitive impairment, even during periods of clinical stability.

This study explores the impact of insomnia on cognitive functioning in 170 outpatients diagnosed with BD, 61.8% of which were women (n=105), grouped by age (<50 years vs. ≥50 years). Standardized and validated instruments were used to assess sleep quality (Oviedo Sleep Questionnaire) and cognitive performance (Screening of Cognitive Impairment in Psychiatry).

Results show that 63.1% of the sample exhibited some degree of cognitive impairment, with notable differences across age groups. Although no significant differences in insomnia prevalence were found by cognitive status, lower sleep satisfaction was associated with cognitive functioning in younger patients (p=0.044). In older patients, only severity of depression was associated with cognitive impairment (p=0.049).

These findings underscore the relevance of age-specific intervention strategies to approach cognitive impairment, focusing on sleep assessment in younger patients with BD, and rather on affective symptoms in older adults with BD.