Psychiatry Research EG

Introduction Studies have proposed that cognitive defi cits are present in a variety of mood states in bipolar disorder (BD). In addition, a few studies have pointed to the presence of sex-related differences in cognitive dysfunction in BD. Aim of the work This comparative study aimed to study the cognitive functioning of BD patients in different episodes, and detect any sex-related differences in cognitive functioning in the studied sample. Patients and methods The recruited sample consisted of 150 patients selected at random from El Maamoura Mental Hospital over 6 months. Four groups were formed: group I, comprising 38 (19 male and 19 female) BD patients having manic episodes; group II, comprising 26 (12 male and 14 female) BD patients having depressive episodes; group III, comprising 36 (20 male and 16 female) patients in remission (euthymic); and group IV, comprising 50 controls matched for age, sex, and education. Clinical and psychiatric evaluations were carried out and psychometric assessment was performed using the 17-item Hamilton Depressive Scale and the Young Mania Rating Scale, as well as cognitive assessments using three tests: Wisconsin’s Card Sorting Test ( WCST), the digit span subtest of the WAIS-R and DSST (the digit symbol subtest of the WAIS-R). Results The BD patients in the three groups having BD showed signifi cant cognitive defi cits compared with controls. Manic and depressive patients showed impairment in attention, working memory, and executive functions. Euthymic patients showed signifi cant impairment in working memory and executive functions. Only euthymic patients revealed a statistically signifi cant sex-related difference in terms of short-term memory, attention, and working memory, with women being worse than men. Interestingly, in the control group a difference in executive functions was reported wherein healthy control women performed signifi cantly better than control men on the WCST-128 (completed signifi cantly more number of categories and committed signifi cantly fewer perseverative errors). Conclusion Cognitive dysfunction should be regarded as a core feature of BD as it was present across all mood states in our sample. In addition, discrepancy has been found between male and female euthymic patients regarding cognitive functions, suggesting a sex-related difference in the clinical expression of BD. Keywords: 17-item Hamilton Depressive Scale, bipolar disorder, cognitive assessments, cognitive dysfunction, digit span subtest of the WAIS-R and DSST (the digit symbol subtest of the WAIS-R), sex difference, Wisconsin’s Card Sorting Test, Young Mania Rating Scale