The cognitive impairments of euthymic patients with early-onset or late-onset bipolar Ⅰ disorder / 中国神经精神疾病杂志

ABSTRACT

Objective To explore the characteristics of cognitive impairments in euthymic patients with early-on?set or late-onset bipolar I disorder (BD-I). Methods Ninety-four with onset age less than 21 (early onset group), 41 eu?thymic patients with onset age above 35 (late onset group) and 135 normal controls with matched education and age were enrolled. Seven classical neuropsychological tests were used to assess attention, processing speed, working memory and executive functions. Results The early-onset group was significantly worse than its corresponding normal controls in 14 indexes of all tests, including digital symbol, digital span, visual graphic reproduction (c1 and c2), time of TMT-A and TMT-B, verbal fluency, number of sorting, error and preserved error in WCST, as well as total score, completed missions, planning time and executing time in TOH (P<0.05). Moreover the effect size of difference were more than 0.4 in verbal fluency, time of TMT-A and TMT-B, and executing time in TOH. Compared with its matched control group, the late-on?set group was significantly impaired in 9 indexes, including digital span, visual graphic reproduction (c1,c2 and total), time of TMT-A, number of error and preserved error in WCST, as well as total score and completed missions in TOH (P<0.05), merely two indexes of TOH with effect size more than 0.4, while the late-onset group was no significantly impaired in digital symbol, TMT-B and verbal fluency. Conclusions There are significant cognitive impairments in euthymic BD-I patients with no matter early-onset or late-onset. But it seems that the cognitive impairments in early-onset bipo?lar disorder are more extensive and serious.