Cognitive Complaints in Bipolar Disorder: Relation to Estimated Illness-Related Objective Cognitive Decline, Functioning, and Quality of Life

OBJECTIVES: Persons with bipolar disorder (BD) often present with cognitive complaints even in the absence of objective cognitive impairment as measured with neuropsychological tests. It remains unclear whether cognitive complaints reflect negative bias or illness-related decline from premorbid functioning, affecting functioning and quality of life (QoL).

METHODS: Data from n = 498 persons with BD and n = 320 healthy controls (HC) were included from a database based on seven studies. We calculated IQ-objective cognition discrepancy scores (-10 to +10; negative scores = lower cognitive performance than premorbid IQ, i.e., estimated 'loss of function') and subjective-objective cognitive discrepancy scores (-10 to +10; negative scores = less subjective than objective difficulties; positive scores = more subjective than objective impairments). We investigated associations between these variables and subjective cognitive complaints, functioning, and QoL with multiple regression models.

RESULTS: Subjective cognitive complaints were associated with poorer global cognitive performance relative to premorbid IQ (i.e., estimated 'loss of function'). More subjective than objective cognitive difficulties was associated with diminished functioning and QoL. A similar association was seen for objective cognitive performance.

CONCLUSIONS: Subjective complaints may indicate a decline from premorbid cognitive function, even if objective cognitive performance is within the normal range after illness onset. More subjective than objective impairment correlates with poorer functioning and QoL. Hence, cognitive management initiatives should be centered around patients with cognitive complaints independent of objective cognitive status.