Executive dysfunction in patients with obstructive sleep apnea syndrome.

AIMS To clarify whether patients with obstructive sleep apnea syndrome (OSAS) have executive dysfunction, to identify the domains of executive function affected and to establish the severity of any dysfunction. METHODS A full-night polysomnography and a comprehensive neuropsychological assessment focusing on executive functions were conducted on 40 newly diagnosed OSAS patients and 20 healthy controls. The severity of dysfunction was analyzed using norm-referenced data. RESULTS All patients and controls were men. The groups did not differ statistically significantly in terms of age, education or intelligence quotient. Patients showed poorer performance than controls on the copy of the Rey-Osterrieth Complex Figure test, the Block Design, the Trails B of the Trail Making Test and the Intra-Extra Dimensional Set Shifting test. Based on the normative data, most OSAS patients performed at a normal level, but a few patients had either mild dysfunction (2.5-12.5%) or moderate to severe dysfunction (5-15%). CONCLUSIONS OSAS patients have lower set-shifting and analysis/synthesis performance than healthy controls. According to the normative data, most patients in the present study had normal performance, but there were also a few patients with more serious deficits.