Epidemiology and clinical phenomenology for Parkinson's disease with pain and fatigue

We conducted a cross-sectional analysis with 901 Parkinson's disease (PD) patients in China to understand the epidemiological characteristics of PD pain among Chinese patients. In addition, we searched PubMed and the China Hospital Knowledge Database for epidemiological studies of pain and fatigue among PD patients from 1999 to 2011 to understand the prevalence of these symptoms around the world and associated clinical features. The 901 PD cases were recruited from 42 university affiliated hospitals randomly selected from seven provincial capitals across four economic regions of China. We documented motor and non-motor symptoms via clinical examinations and questionnaire surveys. Using logistic regression models, we evaluated factors that were associated with PD pain among these Chinese patients. Of the 901 Chinese patients, 269 (29.9%) had PD-related pain. After adjusting for confounders, only dyskinesias (OR = 2.66) and depression (OR = 2.88) were independently associated with PD pain. The literature search identified a total of 16 eligible studies on PD-pain and 19 on PD fatigue with various tools for symptom assessment. The data suggest a crude prevalence of 33.7% for PD pain in Asia and 79.4% in Northern Europe; the prevalence for PD fatigue was 35.4% in Northern Europe and 59.1% in Western Europe. Interestingly, Northern-European PD patients reported the highest prevalence of pain, but the lowest prevalence of fatigue. These studies suggest that motor complications and depression are likely key predictors for PD pain, while disease severity, depression and sleep disturbance are associated with PD fatigue. More studies with standardized methods would be needed to better understand the prevalence of PD pain and fatigue across various regions of the world.