Neurocognition in Unaffected First-Degree Relatives of Patients With Bipolar Disorder Type I From India

The study aims to evaluate the neuropsychological functions of unaffected first-degree relatives of patients with bipolar disorder Type I (BD-I) in comparison with healthy controls. The method was a cross-sectional assessment of 20 first-degree relatives of patients with BD-I and 20 healthy controls. Inclusion criteria for all participants included age between 18 and 55 years, ≥5 years of formal education, right-handedness as per Edinburgh handedness inventory, absence of color blindness as per Ishihara’s isochromatic charts, and a score of >24 on Hindi mental state examination. None of the participants had a current or lifetime diagnosis of a mental disorder on Structured Clinical Interview for DSM-IV , Clinician Version. Neuropsychological assessment was conducted with Trail Making Test A and B, Stroop color and word test, N-Back Verbal Memory Test, and Post Graduate Institute (PGI) Memory Scale. Both the groups were comparable in age, gender distribution, and education. The unaffected first-degree relatives performed poorly on Trail Making Test B and (B-A), indicating a poor cognitive flexibility and set-shifting. The relative group also performed poorly on Mental Balance subtest of PGI Memory Scale. The unaffected first-degree relatives of patients with BD display certain impairments in dorsal prefrontal executive functions which can serve as vulnerability markers for BD.