Pain Characteristics of Parkinson's Disease Using Validated Arabic Versions of the King's Parkinson's Disease Pain Scale and Questionnaire: A Multicenter Egyptian Study

Pain is one of the most common nonmotor symptoms in Parkinson's disease (PD), with variable characteristics among populations. This multicenter Egyptian study aimed to translate and validate the King's Parkinson's Disease Pain Scale (KPPS) and Questionnaire (KPPQ) into Arabic versions and to investigate the pain characteristics in Egyptian people with PD (PWP). A total of 192 PWP and 100 sex- and age-matched controls were evaluated by the KPPS-Arabic and KPPQ-Arabic. Both tools were assessed for test-retest reliability, floor or ceiling effects, construct validity and convert validity. PWP were also assessed by the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Hoehn and Yahr scale (H&Y), Non-Motor Symptom Scale (NMSS), PD Questionnaire-39, and Non-Motor Fluctuation Assessment (NoMoFA). The KPPS-Arabic and KPPQ-Arabic showed inter- and intrarater consistency and high validity, with an acceptable ceiling effect. A total of 188 PWP (97.9%) reported at least 1 type of pain (p < 0.001). The severity and prevalence of all pain domains in the KPPS-Arabic were significantly higher among PWP than among controls (p < 0.001). Fluctuation-related and musculoskeletal pains were the most common (81.3% and 80.7%, respectively). In the PD group, the total and domains of KPPS-Arabic were significantly correlated to the MDS-UPDRS total score and the scores of Parts I, II, III, postural instability gait disorder, axial, and H&Y but not with age or age of onset. The predictors of KPPS-Arabic scores included the total MDS-UPDRS, the part III-OFF, disease duration, the total NMSS, and the NoMoFA scores. The current multicenter study provided validated Arabic versions of the KPPS and KPPQ, which exhibited high reliability and validity, and demonstrated a high prevalence and severity of pain within Egyptian PWP and characterized its determinants.