| Ozdilek and Gunal (2012) [38] Turkey | To examine the impact of motor and non-motor symptoms of non-demented PwPD on the psychological health, burden and QoL of caregivers
“A multidimensional response to physical, physiological, emotional, social and financial stressors associated with caring for a chronically ill patient” (p. 479) | 50 caregivers (37 spouses, 11 children, 2 siblings) | Person’s correlation coefficient (multiple linear regression-results not given)
No | Caregiver burden was positively associated with the patient-related variables; disease stage, disease severity, anxiety, depression and daytime sleepiness |
| Shin et al. (2012) [63] South Korea | To determine factors that predict caregiver burden in spousal and offspring caregiver groups
No definition | 91 caregivers (50 spouses, 41 offspring) | Spearman’s rho Mann-Whitney test Multiple linear regression
No | In the spousal group, mentation was the patient variable that contributed the most to burden. In the offspring group, motor function was the patient variable that most strongly predicted burden |
| Leroi et al. (2012) [36] United Kingdom | To explore the relationship between carer burden and the presence of apathy and impulse control disorders (ICD) in PD patients
“The myriad of physical, mental and socio-economic problems that arise from caring for an individual with a chronic and disabling disease such as PD” (p. 160) | 71 caregivers (38 spouses, 33 adult children) | Linear regression
No | Patient attentional ability accounted for burden in carers of patients with apathy. In carers of patients with ICD dopaminergic load and depression accounted for burden. None of these variables accounted for carer burden in the PD control group |
| Peters et al. (2011) [56] United Kingdom | To explore to what extent patient self-reported health status is associated with carer strain and QoL
No definition | 704 caregivers (626 spouses/ partners, 41 children, 18 other family members, 18 friends or others) | Regression analysis
No | Physical and mental scores of the SF-36 and years since diagnosis correlated with caregiver strain. Mobility and social support were the main patient self-reported PDQ-39 domains predicting caregiver strain |
| Razali et al. (2011) [39] Malaysia | To investigate clinical and socio-demographic factors associated with perceived burden among PD caregivers
Caregivers’ perceptions of their health, social life and financial status suffered because of their caregiving experience | 115 caregivers (51 spouses, 56 children, 8 other relatives) | Correlation Analysis of variance t-test
No | Caregiver burden correlated positively with patient PD stage and patient age. Caregiver burden was also related to her/his race |
| Carter et al. (2010) [26] USA | To compare the difference in negative and positive aspects of strain in young versus older spouse caregivers in early stage PD patients
Role strain-difficulty in fulfilling the caregiving role | 65 caregivers [Spouses, 37 young (40-55 years), 28 old (≥70 years)] | t-test Chi-square test Hierarchical regression analyses
Yes | Compared to the older spouses the younger group reported significantly more strain from the negative variables such as lack of personal resources but not from worry and global strain. When controlling for spouse gender and physical health, the younger spouses explained 13 % of the variance in strain from lack of personal resources |
| Leiknes et al. (2010) [33] Norway | To investigate caregiver distress associated with neuropsychiatric problems in patients with newly diagnosed PD and a control group
“The emotional caregiver distress associated with the mental health status of the patients” (p. 419) | 189 caregivers (134 spouses, 31 children, 18 other relatives, 6 others) | Mann-Whitney U test Chi-square test Spearman’s rho
Yes | PD patients’ next of kin reported significantly more distress than the non-PD control group. Female caregivers reported more symptoms associated with distress. Only depression and apathy distressscores of the NPI correlated with the patient disease stage |