Validation of the Korean version of the 39-Item Parkinson's Disease Questionnaire (PDQ-39)

Is PDQ-39 a reliable measure of quality of life of patients at advanced stages of Parkinson's disease considered for Deep Brain Stimulation

Purpose

Parkinson's disease (PD) significantly impedes, especially at its advanced stages, the health-related quality of life (QoL) of patients. The Parkinson's disease questionnaire (PDQ-39) is a widely-used measure assessing the impact of the disease on the patients' QoL. To date, the reliability of PDQ-39 has not been selectively evaluated for patients at a particular delineated stage of the PD progression. Against this backdrop, the study aimed firstly to evaluate comprehensively the internal consistency reliability of PDQ-39 and the constituent scales specifically for patients at the advanced stages of PD who were candidates for Deep Brain Stimulation (DBS) surgery, and secondly, to compare the Cronbach's alpha coefficients with those reported in other studies conducted with patients across all stages of the PD progression.

Methods

The sample included 36 Bulgarian patients (29 men and 7 women) at advanced stages of PD (Hoehn and Yahr stage 4), PD duration, M = 11.06, SD = 3.50). The internal consistency reliability of the questionnaire and the constituent scales was assessed using three criteria: Cronbach's alpha coefficients, inter-item and item-total correlations.

Results

The internal consistency reliability indicators were satisfactory for the entire instrument and for most of the scales and similar to those reported in previous studies. None of the scales had low internal consistency reliability results across the three criteria. Except for the Communication scale, seven of the eight scales had Cronbach's alpha values that were satisfactory or marginally below the cut off score. All scales had acceptable inter-item correlations. Three of the scales (Emotional Well-Being, Cognition and Communication) contained more than one item with non-satisfactory item-total correlations. With minor exceptions, the removal of the items with low item-total correlations either did not improve or improved marginally or even decreased the Cronbach's alpha coefficients of the respective scale. The Communication scale was the only scale with a Cronbach's alpha coefficient that was both low and comparatively different to other studies and had as well low item-total correlations for all constituent items, thus showing non-satisfactory results on two of the three internal consistency reliability estimates. In contrast, the Mobility scale met all three internal consistency reliability criteria.

Conclusion

PDQ-39 is a reliable tool for assessing the QoL of patients at advanced stages of PD across multiple health-related domains. The questionnaire can be recommended for inclusion in the best practice guidelines for evaluating DBS candidacy and the efficacy of DBS treatment for patients' QoL.

The predictive relationships between advanced dynamic balance and physical activity/quality of life in Parkinson's disease

Gait and balance problems commonly occur in Parkinson's disease (PD). However, balance tasks with only one performance objective (e.g., sit-to-stand) may not be sufficient, compared to dual motor tasks (e.g., carrying a tray while walking), to be applied to the assessments and interventions which are designed to promote PD patients' balance functioning, physical activity (PA) and health-related quality of life (HQoL). The aim of this study, therefore, was to determine whether advanced dynamic balance, measured by a demanding motor-motor dual task, is a significant predictor of PA/HQoL in older adults with and without PD. Participants with (n = 22) and without (n = 23) PD were assessed using the Berg Balance Scale (BBS), the single leg hop and stick series task (SLHS), the Physical Activity Scale for the Elderly (PASE), and the Parkinson's Disease Questionnaire-39 (PDQ39). We calculated the R² change, namely the incremental validity, between the multiple regression models before and after adding the scores on the BBS/SLHS. While controlling for biological and socioeconomic covariates, competence in the SLHS task provided moderate and large levels of incremental validity to PA (ΔR² = 0.08, Cohen's f² = 0.25, p = .035) and HQoL (ΔR² = 0.13, Cohen's f² = 0.65, p < .001), respectively. In particular for participants with PD, the SLHS explained significantly more variance in HQoL in relation to psychosocial functioning (ΔR² = 0.25, Cohen's f² = 0.42, p = .028) compared to the BBS (p = .296). Assessing advanced dynamic balance by means of a highly demanding dual-task paradigm was not only strongly associated with PA but also covered a wider spectrum of HQoL components. This approach is recommended for use in evaluations and interventions carried out in clinical and research settings in order to promote healthy living.

Exercise Management Using a Mobile App in Patients With Parkinsonism: Prospective, Open-Label, Single-Arm Pilot Study

Background

Patients with parkinsonism have higher inactivity levels than the general population, and this results in increased comorbidities. Although exercise has benefits for motor function and quality of life (QOL) in patients with parkinsonism, these patients face many barriers to exercise participation, such as lack of motivation, fatigue, depression, and time constraints. Recently, the use of mobile apps has been highlighted as a remote exercise management strategy for patients with chronic diseases.

Objective

This study aimed to evaluate the effects of home-based exercise management with a customized mobile app on the exercise amount, physical activity, and QOL of patients with parkinsonism.

Methods

This was a prospective, open-label, single-arm pilot study. The therapist installed the app in the smartphones of the participants and educated them on how to use the app. The therapist developed an individualized multimodal exercise program that consisted of stretching, strengthening, aerobic, balance and coordination, and oral-motor and vocal exercises. Participants were encouraged to engage in an 8-week home-based exercise program delivered through a customized app. The alarm notifications of the app provided reminders to exercise regularly at home. The primary outcome was the exercise amount. The secondary outcomes were assessed using the International Physical Activity Questionnaire (IPAQ), Parkinson’s Disease Questionnaire-39 (PDQ-39), and Geriatric Depression Scale (GDS). The usability of the customized app was assessed using a self-report questionnaire.

Results

A total of 21 participants with parkinsonism completed the intervention and assessment between September and December 2020 (mean age: 72 years; women: 17/21, 81%; men: 4/21, 19%). The participants reported a significant increase in the total amount of exercise (baseline: mean 343.33, SD 206.70 min/week; 8-week follow-up: mean 693.10, SD 373.45 min/week; P<.001) and in the amount of each exercise component, including stretching, strengthening, balance and coordination, and oral-motor and vocal exercise after 8 weeks. Analysis of the secondary outcomes revealed significant improvements in the IPAQ (P=.006), PDQ-39 (P=.02), and GDS (P=.04) scores. The usability of the program with the mobile app was verified based on the positive responses such as “intention to use” and “role expectation for rehabilitation.”

Conclusions

Exercise management with a customized mobile app may be beneficial for improving exercise adherence, physical activity levels, depression management, and QOL in patients with parkinsonism. This remotely supervised technology-based, reinforcing, and multimodal exercise management strategy is recommended for use in patients with parkinsonism. In addition, this program proved useful as an alternative exercise management strategy during the COVID-19 pandemic when patients with Parkinson disease were less physically active than before and showed aggravation of symptoms. However, additional clinical trials are needed to evaluate the efficacy of this exercise program in a large population and to confirm its disease-modifying effects.

Quality of life in Parkinson's disease: A systematic review and meta-analysis of comparative studies

BACKGROUND

Studies regarding the impact of Parkinson's disease (PD) on quality of life (QOL) have reported conflicting results, and the underlying QOL domains require further study. In order to understand the association between PD and QOL, we conducted this meta-analysis to systematically compare QOL between PD patients and healthy controls.

METHOD

The PubMed, PsycINFO, EMBASE, and Web of Science databases were systematically searched. Data were analyzed using the random-effects model.

RESULTS

Twenty studies covering 2707 PD patients and 150,661 healthy controls were included in the study. Compared with healthy controls, PD patients had significantly poorer QOL overall and in most domains with moderate to large effects sizes. Different QOL measures varied in their association with quality of life, with the Parkinson's Disease Questionnaire-39 (PDQ-39) having the largest effect size (standard mean difference, SMD = -1.384, 95% CI: -1.607, -1.162, Z = 12.189, P < 0.001), followed by the Europe Quality of Life Questionnaire-visual analogue scale (EQ-VAS) (SMD = -1.081, 95% CI: -1.578, -0.584, Z = -4.265, P < 0.001), Europe Quality of Life Questionnaire-5D (EQ-5D) (SMD = -0.889, 95% CI: -1.181, -0.596, Z = -5.962, P < 0.001), and the Short-form Health Survey (SF) scales (physical dimension: SMD = -0.826, 95% CI: -1.529, -0.123, Z = -2.303, P = 0.021; mental dimension: SMD = -0.376, 95% CI: -0.732, -0.019, Z = -2.064, P = 0.039).

CONCLUSION

PD patients had lower QOL compared with healthy controls in most domains, especially in physical function and mental health. Considering the negative impact of poor QOL on daily life and functional outcomes, effective measures should be developed to improve QOL in this population.

Quality of life in Parkinson's disease: Italian validation of the Parkinson's Disease Questionnaire (PDQ-39-IT)

Translation and cross-cultural adaptation of the 39-item Parkinson's Disease Questionnaire (PDQ-39) to the Italian culture was performed by Oxford University Innovation in 2008, but this version has never been validated. Therefore, we performed the process of validation of the Italian version of the PDQ-39 (PDQ-39-IT) following the "Consensus-Based Standards for the Selection of Health Status Measurement Instruments" checklist. The translated PDQ-39-IT was tested with 104 patients diagnosed with Parkinson's disease (PD) who were recruited between June and October 2017. The mean age of the participants was 65.7 ± 10.2 years, and the mean duration of symptoms was 7.4 ± 5.3 years. The internal consistency of the PDQ-39-IT was assessed by Cronbach's alpha and ranged from 0.69 to 0.92. In an assessment of test-retest reliability in 35 of the 104 patients, the infraclass correlation coefficient (ICC) ranged from 0.85 to 0.96 for the various subitems of the PDQ-39-IT (all p < 0.01). Spearman's rank correlation coefficient for the validity of the PDQ-39-IT and the Italian version of the 36-Item Short Form (SF-36) was - 0.50 (p < 0.01). The results show that the PDQ-39-IT is a reliable and valid tool to assess the impact of PD on functioning and well-being. Thus, the PDQ-39-IT can be used in clinical and research practice to assess this construct and to evaluate the overall effect of different treatments in Italian PD patients.

Predictive model for health-related quality of life in patients with Parkinson's disease

This study was conducted to develop and test a prediction model that explains health-related quality of life (HRQoL) of patients with Parkinson's disease (PD). Participants were 248 patients with PD enrolled in the neurology clinic of a university hospital in Seoul, Korea. The data were collected through structured questionnaires from March 1 to July 5, 2013. Motor fluctuations, depression, sleep disturbances, fatigue, and activities of daily living had significant direct effects on the quality of life of PD patients. Disease severity, social support, pain, sleep disturbances, fatigue, and activities of daily living had significant indirect effects on patients' quality of life. These predictive variables explained 77.4% of the total variance. The assessment of HRQoL in PD should be considered along with the variables affecting it, including social support. In addition, strategies to enhance social support may be useful for improving the quality of life for patients with PD.