Neurocognitive and psychosocial functioning profiles in bipolar disorder and comorbid attention deficit hyperactivity disorder: A systematic review and meta-analysis

Bipolar disorder (BD) and attention deficit hyperactivity disorder (ADHD) are chronic psychiatric conditions with significant impacts on neurocognitive and psychosocial functioning. Co-occurrence of BD and ADHD (BD-ADHD) presents unique clinical challenges and could exacerbate cognitive and functional impairments. This systematic review and meta-analysis aimed to provide an updated synthesis of the differences in neurocognitive and psychosocial functioning between patients with BD-ADHD, BD, ADHD, and healthy controls (HC). A comprehensive systematic search identified 5639 records, with 34 studies meeting the inclusion criteria for a systematic review and 31 for the meta-analysis. There were no significant differences in cognitive performance across none of the evaluated cognitive domains between BD-ADHD and BD patients. BD-ADHD patients exhibited significantly lower visual memory (SMD=-0.29, 95 % CI=-0.53,-0.04; p = 0.022) compared to ADHD patients. Compared to HC, BD-ADHD patients showed poorer performance in processing speed (SMD=-0.54, 95 % CI= -0.86,-0.22; p < 0.001), sustained attention (SMD=-0.40, 95 % CI=-0.62, -0.19; p < 0.001), visual memory (SMD=-0.47, 95 % CI=-0.69,-0.26; p < 0.001), working memory (SMD=-0.79, 95 % CI=-1.13,-0.44; p < 0.001), cognitive flexibility and higher-order executive functions (SMD=-0.52, 95 % CI=-0.84,-0.20; p = 0.001), and verbal memory (SMD=-0.95, 95 % CI=-1.43,-0.47; p < 0.001). Psychosocial functioning was significantly worse in BD-ADHD patients compared to BD (SMD=-0.46; p < 0.001), ADHD (SMD=-1.00; p < 0.001), and HC (SMD=-3.54; p < 0.001). Our results suggest that the co-occurrence of BD and ADHD is associated with significant neurocognitive and psychosocial impairments. These findings underscore the need for targeted interventions to address the unique challenges of this comorbid condition, informing clinical practice and guiding future research.