Neurocognitive functioning in patients recently diagnosed with bipolar disorder

Cognitive dysfunction in bipolar disorder (BD) is well established in the literature; however, there are few studies of neurocognition in patients early in the course of the illness. In this study we compare neurocognitive function in a cohort of first-contact mania patients with a healthy control group matched for age, gender, and education.

Patients with a first manic episode (FM) (n = 34) or previous untreated manic episodes (PM) (n = 21) were neuropsychologically tested following their first treated manic episode. A total of 110 matched healthy control comparison subjects were also tested. The following cognitive domains were evaluated: verbal and visual learning and memory, attention, processing speed, executive functioning, and IQ. Results were corrected for speed of processing differences and were compared with previously reported results for multiple-episode BD patients.

BD patients early in their disease course showed impairments in psychomotor speed, attention, learning and memory, executive functioning, and IQ. When controlling for speed of processing, measures of visuoconstructive reasoning and motor dexterity remained statistically significant. Eighteen percent of FM and 16% of PM patients were found to have clinically significant neurocognitive impairment. No significant relationship between clinical symptoms and neurocognition was found. The first-contact mania patients studied were found to have smaller neurocognitive deficits compared to multiple-episode patients in previous studies.

Neurocognitive dysfunction is present in early BD and is clinically significant for a proportion of patients. Our findings also suggest that neurocognitive dysfunction may increase with illness progression.