Purpose: The purpose of this study was to assess the clinical factors which define the quality of life (QOL) in patients with Parkinson’s disease (PD), and to investigate the relationships between the main contributory factors of the health profile and the overall QOL.
Methods: This prospective study assessed the QOL using the World Health Organization Quality of Life scale brief version (WHOQOL-BREF) Questionnaire. All patients were tested using the Unified Parkinson’s Disease Rating Scale (UPDRS) score, Hoehn and Yahr (HY) stage, Mini-Mental State Examination (MMSE), Schwab and England Activities of Daily Living scale (ADL), Geriatric Depression Scale (GDS), Fatigue Severity Scale (FSS) and the levodopa equivalent dose (LED). Stepwise model of multiple linear regression analysis was used to assess the impact of independent variables on the mean WHOQOL-BREF score.
Results: The mean WHOQOL-BREF score was 11.52 ± 3.94. Total and each domain (physical, psychological, social relationships, and environment domains) WHOQOL-BREF scores were positively correlated with education years, MMSE, and ADL. However, they were negatively correlated with LED; HY stage; UPDRS I, II, and III scores; GDS score; and FSS score (all p<0.0001). Multiple linear regression analysis showed that only UPDRS I and II, GDS, and FSS scores were independently associated with the mean WHOQOL-BREF score.
Conclusion: Based on our results, the impairment of non-motor features including activities of daily living and mentation, behavior, and mood and fatigue (UPDRS I and II, FSS, and GDS) affect the QOL in patients with PD. It is crucial to detect non-motor symptoms in the early phases and prompt treatment, which might help to improve the quality of life.