Objectives. The aim of the study was to determine the relationship between symptom severity and both working memory and executive function integrity in two groups of patients: with depression or hypomania/mania.
Method. Participants in the study were60 inpatients from the province of Lodz, diagnosed with bipolar affective disorder by a psychiatrist using the ICD-10 diagnostic criteria. They were treated at the 2ndPsychiatric Clinic CSK or the Babinski Hospital. Thirty patients in the 18‒68 age range (mean age 46 years, 12 men and 18 women) fulfilled the criteria for depressive episode (the Hamilton Depression Rating Scale score >11), and 30 patients aged 23‒68 (mean age = 48 years; 12 men, 18 women) fulfilled the hypomanic or manic episode criteria (scoring on the Young Mania Rating Scale >11 points). In the neuropsychological assessment various types of working memory and executive functions were evaluated.
Results. No relationship was found between severity of depressive symptoms and integrity of working memory and executive functions. On the other hand, higher severity of manic symptoms was associated with impairments of executive functions and of various aspects of working memory. However, these relationships were curvilinear, which suggests that low levels of manic symptoms may improve the patient's cognitive functioning, and only higher severity of mania leads to cognitive impairments.
Conclusions. Cognitive functioning seems to be significantly related to severity of manic symptoms, being unrelated to the severity of depressive symptoms.