Characteristics of fatigue and correlation with other symptoms of Parkinson's disease

Objective To study the characteristics of fatigue and the correlation between fatigue and other symptoms of Parkinson's disease (PD). Methods According to Fatigue Severity Scale (FSS), 100 PD patients enrolled in this study were divided into fatigue group (FSS > 4 score, N = 58) and non-fatigue group (FSS ≤ 4 score, N = 42). Unified Parkinson's Disease Rating Scale Ⅲ (UPDRS Ⅲ), revised Hoehn-Yahr stage and modified Webster score were used to investigate the severity of motor symptom. Non-Motor Symptoms Scale (NMSS), Mini-Mental State Examination (MMSE), Hamilton Depression Rating Scale (HAMD), Hamilton Anxiety Rating Scale (HAMA), Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI) were adopted to measure the severity of non-motor symptom. In addition, UPDRSⅡ was used to evaluate the activities of daily living and 39-Item Parkinson's Disease Questionnaire (PDQ-39) was used to measure life quality of PD patients, respectively. Results There were 58 out of 100 PD patients having fatigue symptom, namely the occurrence rate of fatigue was 58%. The occurrence rate of daytime nap (χ2= 16.256, P = 0.000), fatigue (χ2 = 84.639, P = 0.000), lack of interest (χ2 = 10.705, P = 0.001), lack of passion (χ2 = 9.350, P = 0.002), depression (χ2 = 9.350, P = 0.002), anxiety/panic (χ2 = 4.625, P = 0.032), emotional apathy (χ2 = 22.032, P = 0.000), anhedonia (χ2 = 18.247, P = 0.000), poor memory (χ2 = 4.366, P = 0.037), urgency of urination (χ2 = 5.774, P = 0.016), frequency of micturition (χ2 = 5.774, P = 0.016), hard in sex life (χ2 = 3.877, P = 0.049), and decreased sense of smell or taste (χ2 = 5.360, P = 0.021) were significantly higher in PD patients of fatigue group than those in non-fatigue group. UPDRSⅢ scores (t = 6.374, P = 0.000), revised Hoehn-Yahr stage (Z = -3.345, P = 0.001), modified Webster score (t = 6.819, P = 0.000), NMSS (t = 2.923, P = 0.011), HAMD (Z = - 2.451, P = 0.014), HAMA (t = 5.417, P = 0.000), ESS (Z = - 2.116, P = 0.034), UPDRS Ⅱ (Z = - 3.115, P = 0.002) and PDQ - 39 (Z = - 2.696, P = 0.007) were significantly higher in PD patients of fatigue group than those in non - fatigue group. Spearman rank correlation analysis indicated that FSS scores had high positive correlation with modified Webster score (rs = 0.622, P = 0.000) and NMSS (rs = 0.611, P = 0.000), moderate positive correlation with duration (rs = 0.582, P = 0.000), UPDRSⅢ (rs = 0.573, P = 0.000), revised Hoehn-Yahr stage (rs = 0.542, P = 0.000), HAMD (rs = 0.505, P = 0.000), HAMA (rs = 0.477, P = 0.000), ESS (rs = 0.474, P = 0.000), PSQI (rs = 0.410, P = 0.000), UPDRS Ⅱ (rs = 0.559, P = 0.000) and PDQ-39 (rs = 0.578, P = 0.000), and low negative correlation with MMSE (rs=- 0.258, P = 0.000). Conclusions The occurrence of fatigue in PD is high, which has interaction effect with other symptoms of PD, consequently affecting the life quality of PD patients.