| Abstract [eng] |
The aim of the study: to evaluate the cognitive functions of patients with early-stage Parkinson‘s disease (PD) without dementia using Cambridge Neuropsychological Test Automated Battery (CANTAB Eclipse 3.0.0), to compare the obtained results with the data of control subjects, to determine the associations of the variables of cognitive testing with biological markers and clinical non-cognitive symptoms of PD. Objectives: to examine attention, memory, visuospatial and executive functions of patients with early-stage PD without dementia using CANTAB Eclipse 3.0.0 and to compare the obtained results with the data of control subjects; to investigate the relationship between the cognitive functions of patients with early-stage PD and the severity of disease measured by UPDRS score, the echogenic properties of brainstem nigral substance (SN) examined by transcranial sonography (TCS), the striatal binding of presinaptic dopamine transporter determined by single-photon emission computed tomography (SPECT) with I¹²³-FP-CIT, sleep, fatigue, demographic factors and quality of life scores, the usage of medications for early-stage PD; to analize the diagnostic characteristics of particular computerised tests for evaluation of cognitive function in patients with early-stage PD. Methods. The study was performed at the Department of Neurology of Vilnius University Hospital Santariškių Klinikos. 115 patients diagnosed with clinically probable early-stage PD who met inclusion criteria and did not have any of exclusion criteria and 42 control subjects matched by age, gender and duration of education who did not have previous diagnosis of PD, other neurodegenerative disorder or non-degenerative parkinsonism were recruited into the study. All the participants have been interviewed with the special study questionnaire, acquiring demographic, disease history, medication data, have fullfilled the questionnaires regarding to the quality of life, fatigue, quality of sleep, daytime somnolence, mood and have undergone general clinical and neurological assessment and testing with the cognitive battery composed of 9 tests empirically chosen from CANTAB Eclipse 3.0.0. 48 (41.7%) patients used medications for PD. TCS was performed in 75 (65.2%) PD patients and 40 (95.2%) controls; outcome measures: appearance of SN (categorised normal or hyperechogenic) and measurement of the area (cm²) of SN. SPECT with I¹²³-FP-CIT was performed in a subgroup of PD patients (N=36; 31.3%) according to standard protocol. Conclusions: the cognitive dysfunction of PD patients according to computerised tests results is observed in the early motor stage of the disease. The possible PD-MCI was diagnosed in 27% of study patients with early-stage PD. Disorders of attention, working memory and executive function in drug-naïve early-stage PD patients correlate with the severity of disease measured by Hoehn-Yahr stage, UPDRS score and burden of motor symptoms. There is no linear association between the cognitive functions of early-stage PD patients and the size of area of hyperechogenic brainstem SN evaluated by TCS. Working memory, visuospatial function, timing, cognitive speed and sustained attention of early-stage PD patients are associated with the striatal binding of presinaptic dopamine transporter determined by SPECT with I¹²³-FP-CIT. The main clinical factors having impact on cognitive functions in early-stage PD patients are fatigue, depression and sleep disorders, less accounted for age and education. The cognitive dysfunction in early-stage PD is associated with worse quality of life. The medications for early-stage Parkinson‘s disease have heterogenic impact on cognitive functions. The tests of computerised battery CRT, RVP, SSP, OTS, SRM, SWM, CGT, GNT, PAL are suitable for evaluation of cognitive functions of early-stage PD patients. The diagnostic value of computerised cognitive testing set in diagnosing early PD is increased by evaluation of hyperechogenic SN area on TCS and sleep quality with PDSS. |
