Objectives Fatigue and apathy are two of the most common and most disabling non-motor symptoms of Parkinson's disease (PD). They have a high coincidence and can often be confused; moreover, their relationship is not fully understood. The aim of our study was to describe the coincidence of apathy with different fatigue domains in the presence/absence of depression and to separately describe the associations of different aspects of primary and secondary fatigue with apathy and other clinical and disease-related factors. Materials and methods A total of 151 non-demented patients with PD were examined using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS), Starkstein Apathy Scale, Multidimensional Fatigue Inventory (MFI), Beck Depression Inventory-II, and Epworth Sleepiness Scale. Results The prevalence and severity of fatigue and apathy were significantly higher in depressed PD patients. However, our results show that depression, fatigue, and apathy can be clearly distinguished in PD. Apathy was associated with the MFI's-reduced motivation domain in both depressed and non-depressed patients. However, apathy was associated with mental fatigue aspects only in non-depressed patients, and it was not related to the physical aspects of fatigue in any of the studied groups. Conclusions Although the pathophysiology of fatigue and apathy in PD is clearly multifactorial, in a proportion of PD patients, these symptoms are associated with depression, dopaminergic depletion in the mesocorticolimbic structures, and disruption of the prefrontal cortex-basal ganglia axis. Therefore, in some PD patients, adequate management of depression and optimal dopaminergic medication may improve both fatigue and apathy.
Parkinson’s disease (PD) is the second most common still relentlessly progressive neurodegenerative disorder with a long period in which the pathophysiological process is already spreading but cardinal motor symptoms are not present. This review outlines the major developments and milestones in our understanding of PD that have shaped the way we define this disorder. Past criteria and definitions of PD have been based on clinical motor manifestations enabling diagnosis of the disease only in later symptomatic stages. Nevertheless, with advancing knowledge of disease pathophysiology and aim of early disease detection, a major shift of the diagnostic paradigm is being advocated towards a biological definition similar to other neurodegenerative disorders including Alzheimer’s disease and Huntington’s disease, with the ultimate goal of an earlier, disease course modifying therapy. We summarize the major pillars of this possible approach including in vivo detection of neuronal α-synuclein aggregation, neurodegeneration and genetics and outline their possible application in different contexts of use in the frame of biological PD definition.
Abstract This study was addressed to determine the presence of Parkinson disease (PD) manifestations, their distribution according to motor subtypes, and the relationships with health-related quality of life (QoL) using the recently validated European Parkinson’s Disease Association sponsored Parkinson’s Disease Composite Scale (PDCS). Frequency of symptoms was determined by the scores of items (present if >0). Using ROC analysis and Youden method, MDS-UPDRS motor subtypes were projected on the PDCS to achieve a comparable classification based on the PDCS scores. The same method was used to estimate severity levels from other measures in the study. The association between the PDCS and QoL (PDQ-39) was analyzed by correlation and multiple linear regression. The sample consisted of 776 PD patients. We found that the frequency of PD manifestations with PDCS and MDS-UPDRS were overlapping, the average difference between scales being 5.5% only. Using the MDS-UPDRS subtyping, 215 patients (27.7%) were assigned as Tremor Dominant (TD), 60 (7.7%) Indeterminate, and 501 (64.6%) Postural Instability and Gait Difficulty (PIGD) in this cohort. With this classification as criterion, the analogous PDCS-based ratio provided these cut-off values: TD subtype, ≥1.06; Indeterminate, <1.06 but >0.65; and PIGD, <0.65. The agreement between the two scales on this classification was substantial (87.6%; kappa = 0.69). PDCS total score cut-offs for PD severity were: 23/24 for mild/moderate and 41/42 for moderate/severe. Moderate to high correlations ( r = 0.35–0.80) between PDCS and PDQ-39 were obtained, and the four PDCS domains showed a significant independent influence on QoL. The conclusions are: (1) the PDCS assessed the frequency of PD symptoms analogous to the MDS-UPDRS; (2) motor subtypes and severity levels can be determined with the PDCS; (3) a significant association between PDCS and QoL scores exists.
Aims and objectives To explore whether self‐rated health acts as a potential mediator in the association between functional status and health‐related quality of life in Parkinson's disease. Background Older persons (as most patients with Parkinson's disease are) who reported poor self‐rated health compared with those with excellent self‐rated health were two‐and‐a‐half times more likely to have experienced a decline in functional ability. Design Cross‐sectional. Methods Socio‐demographic and clinical data of the patients ( n = 176) were obtained during a structured interview and from medical records. Functional status was measured with the Unified Parkinson's Disease Rating Scale (total score), self‐rated health with the first item of the Short‐Form 36‐item Health Survey Questionnaire and health‐related quality of life with the disease‐specific questionnaire called the Parkinson's Disease Quality of Life Questionnaire‐39. Multiple linear regression analyses and the Sobel test were employed to assess mediation. Results Self‐rated health seems to have a mediating effect on the association between functional status and health‐related quality of life. The Sobel test confirmed an indirect effect of functional status via self‐rated health on health‐related quality of life and showed a statistically significant indirect effect of functional status on health‐related quality of life via self‐rated health against the direct route without the mediator. Conclusions Self‐rated health partially mediates the deteriorating effect of functional status on health‐related quality of life. Relevance to clinical practice Supportive and adaptation psychosocial intervention programmes leading to restored self‐rated health may enhance the quality of life regardless of disability in Parkinson's disease.
The Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) is a newly developed tool to assess Parkinson's disease (PD). Changes in scores on the scale over the course of PD, including increasing disease duration and Hoehn and Yahr (HY) stages, have not been described. The objectives of this study were to analyze MDS-UPDRS scores on Parts I through IV and their differences based on HY stage and disease duration in a large cohort of patients with PD.For this cross-sectional study, demographic data and MDS-UPDRS scores were collected, including HY stage. Subscores on MDS-UPDRS Parts I through IV were analyzed using 1-way analyses of variance for each HY stage and in 5-year increments of disease duration. Part III (motor assessment) scores were analyzed separately for on and off states.The mean age of the 3206 patients was 65.8 ± 10.6 years, 53.3% were men, the mean disease duration was 11.5 ± 4.6 years, and the median HY stage was 2 (range, 0-5); 2156 patients were examined in an on state and 987 were examined in an off state. Scores for all MDS-UPDRS parts increased significantly through HY stages 1 through 5, with an average increase of 3.8, 7.7, 14.6, and 2.0 points consecutively for parts I through IV, respectively. For the 5-year increments of disease duration, MDS-UPDRS subscores increased by an average of 1.6, 3.3, 4.2, and 1.4 points consecutively for parts I through IV, respectively. This increase was significant only during the first 15 years of disease for all 4 parts, including part III scores evaluated in both on and off states.MDS-UPDRS scores for all 4 parts increase significantly with every HY stage and also with 5-year increments of disease duration in the first 15 years of the disease.