The importance of educational and psychological factors in Parkinson's disease quality of life

OBJECTIVE: To define the factors correlated with quality of life (QoL) in patients with idiopathic Parkinson's disease (PD). BACKGROUND: PD has a substantial impact on QoL. Although several clinical factors have been associated with QoL in PD, the influence of patient's education still remains controversial. METHODOLOGY: A consecutive series of patients with PD were examined using the unified Parkinson's Disease Rating Scale (UPDRS part I, II, III), Schwab and England (SE), and Hoehn and Yahr stage (H&Y). QoL was rated with the PDQ-39, cognition with the Mini-Mental State examination (MMSE), and the presence of depressive symptoms with the geriatric depression scale (GDS). Patient's characteristics, estimated cumulative levodopa dose (CLD), UPDRS, H&Y, MMSE and GDS were correlated with the PDQ-39 using univariate and multiple regression analysis. RESULTS: A total of one hundred 58 patients (68 men, 90 women) with a mean age of 65.6 +/- 9.3 years, PD duration of 8.1 +/- 10.6 years, and education of 6.6 +/- 3.9 years were included. The mean PDQ-39 was 48.8 +/- 27.8, mean MMSE was 25.7 +/- 4, and mean GDS was 11.7 +/- 6.8. Using stepwise multiple regression analysis, the most important predictive factors were depression, UPDRS part I, UPDRS part II, and educational background, which accounted for a 61% of the variability of the PDQ-39 scores. CONCLUSIONS: In our PD sample, educational, behavioural, and psychological factors influenced life satisfaction more than physical ones.