Influencing effect of non-motor symptom clusters on quality of life in Parkinson's disease
Introduction
Parkinson's disease (PD) is a chronic progressive neurodegenerative disorder characterized by dopaminergic neuronal loss in the substantia nigra and other brain regions [1]. Patients with PD not only experience motor symptoms including tremor, rigidity, bradykinesia, and postural instability, but also non-motor symptoms (NMSs) including anxiety, depression, sleep disturbance, and fatigue [2].
Non-motor symptoms of PD have a substantial negative impact on quality of life (QoL) [3], [4], [5], [6]. Most PD patients experience NMS and suffer from a higher frequency of NMS as the disease progresses [7]. The large-scale multicenter PRIAMO study showed that 98.6% of PD patients experienced NMS, with a mean number of 7.8 NMS per patient (range, 0–32) [8].
Previous studies of NMS in PD have focused mainly on single or isolated NMS such as dementia, mood, fatigue, sleep disturbance, and pain [9], [10], [11], [12], [13], [14]. Although this approach has led to a better understanding of each NMS, it has major limitations because most PD patients have multiple and various NMSs.
A ‘symptom cluster’ has been defined as a group of more than two symptoms that occur concurrently and are interrelated to each other; they may or may not have a common etiology [15]. Each symptom in the cluster is independent, but strongly interrelated, and one symptom can impact another symptom through its effect on a third symptom [15], [16], [17], [18].
Most studies thus far have focused on a single NMS in an attempt to identify the NMS that has the biggest impact on QoL or to assess its effect on QoL depending on its severity. However, little information is available on which NMSs form clusters, how clusters form depending on patient condition, and the impact of formed clusters on patient's QoL.
Understanding the non-motor symptom cluster of PD patients can be beneficial for the following reasons. First, it can contribute to identifying the significant symptoms that patients experience but do not report. Second, it can anticipate potential concomitant symptoms that may be manifested in the future, thereby providing effective patient management methods to be used over the course of time. Therefore, investigation of this complex effect of simultaneously occurring NMS in PD is essential for the successful management of this disease and the improvement of QoL in PD patients [19], [20]. Therefore, we investigated the comprehensive features of non-motor symptom cluster (NMSC) and their effects on QoL in PD patients.
Section snippets
Study design and patients
Descriptive cross-sectional design was used. We recruited 180 PD patients between January 1 and April 30, 2013 from Asan Medical Center, Seoul, Korea. Inclusion criteria for the present study were: (1) patients must have been diagnosed with PD based on the United Kingdom Parkinson's Disease Society Brain Bank criteria [21]; (2) 20 years of age or older; and (3) no past history of other major health problems that could potentially influence the NMS, such as active cancer and/or chronic renal
Characteristics of subjects
The demographic and clinical characteristics of the study subjects are summarized in Table 1. Of the 180 PD patients, there were 74 men and 106 women whose mean age was 62.6 ± 10.2 years (range, 28–81 years). The mean age at onset of PD was 55.6 ± 11.6 years (range, 22–80 years) and the mean disease duration was 7.2 ± 5.7 years (range, 0.5–24.0 years). The median Hoehn and Yahr stage was 2 (interquartile range, 2–3).
Characteristics of NMS
Among the 180 PD patients, 178 patients (98.8%) experienced NMS and 172 patients (96.56%)
Discussion
The present study suggests that PD patients may have a specific NMSC and NMSCs have a negative effect to their QoL. Our results have clinical implications, as we suggest that NMS of PD patients should be assessed and managed based on the clusters of complex NMS in PD.
Our results showed that the frequency of NMS in PD was 98.8%. Consistent with previous reports [8], 96.6% (n = 172) of PD patients in the study reported symptoms in at least two domains of NMS, with an average number of 5.1 per PD
Conclusions
PD patients with NMS may have a specific cluster pattern of NMSC. Some NMSCs may have a negative impact on QoL. Understanding the clinical implications of NMSC in PD patients may provide better therapeutic interventions.
Conflict of interest
The authors declare that they have no competing interests.
Acknowledgments
This paper was supported by research funds of Chonbuk National University in 2012.
References (30)
- et al.
Neuropathology of dementia in a large cohort of patients with Parkinson's disease
Parkinsonism Relat Disord
(2013) - et al.
Symptom cluster research: conceptual, design, measurement, and analysis issues
J Pain Symptom Manage
(2006) - et al.
Impact of cancer-related symptom synergisms on health-related quality of life and performance status
J Pain Symptom Manage
(2008) - et al.
Gender differences in motor and non-motor symptoms among Sardinian patients with Parkinson's disease
J Neurol Sci
(2012) - et al.
Gender and onset age-related features of non-motor symptoms of patients with Parkinson's disease: a study from Southwest China
Parkinsonism Relat Disord
(2013) - et al.
Disease duration-related differences in non-motor symptoms: a study of 616 Chinese Parkinson's disease patients
J Neurol Sci
(2013) - et al.
Ageing and Parkinson's disease: substantia nigra regional selectivity
Brain
(1991) Nonmotor complication in Parkinson's disease
Mov Disord
(2005)- et al.
Quality of life in Parkinson's disease: the relative importance of the symptoms
Mov Disord
(2008) - et al.
What are the most important nonmotor symptoms in patients with Parkinson's disease and are we missing them?
Mov Disord
(2010)
On behalf of the NMSS validation group. The impact of non-motor symptoms on health-related quality of life of patients with Parkinson's disease
Mov Disord
Nonmotor symptoms are independently associated with impaired health-related quality of life in Chinese patients with Parkinson's disease
Mov Disord
The metric properties of a novel non-motor symptoms scale for Parkinson's disease: results from an international pilot study
Mov Disord
The priamo study: a multicenter assessment of nonmotor symptoms and their impact on quality of life in Parkinson's disease
Mov Disord
Magnetic resonance imaging: a biomarker for cognitive impairment in Parkinson's disease?
Mov Disord
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