Impact of Neuropsychiatric Symptoms on the Quality of Life of Subjects with Parkinson's Disease

BACKGROUND

Neuropsychiatric symptoms in Parkinson's disease (PD) are frequent. Impact of neuropsychiatric symptoms on quality of life has recently become a relevant topic of research due to its potential to develop targeted therapies to improve quality of life.

OBJECTIVE

To determine the impact of neuropsychiatric symptoms in patients with PD using the Parkinson's Disease Questionnaire Short Form (PDQ-8).

METHODS

Consecutive patients with PD were evaluated with the Scale for Evaluation of Neuropsychiatric Disorders in Parkinson's disease (SEND-PD) and PDQ-8 scales separately. Association between neuropsychiatric symptoms and quality of life was explored using, means comparisons, correlation coefficients and multiple regression models.

RESULTS

A total of 492 patients were included for the study. Overall, 44.5% had psychotic symptoms, 76.5% had alterations on mood/apathy domains, and 27% had an impulse control disorder. All neuropsychiatric symptoms had an effect on the PDQ-8 with a moderate to large effect size. Correlation coefficients ranged from 0.17 to 0.63 between neuropsychiatric symptoms and quality of life (p <  0.001, in all cases). The regression model showed that mood/apathy alterations and impulse control disorders, along with MDS-UPDRS III accounted for 49.8% of variance in the PDQ-8 simplified index (F = 122.98; p <  0.001). Mood/apathy alterations showed the highest correlation coefficient (0.63, p <  0.001) and β (0.53, p <  0.001).

CONCLUSIONS

Both the presence and severity of neuropsychiatric symptoms, in particular mood/apathy alterations,had a significant impact on quality of life in subjects with PD.

Convergent validation of EQ-5D-5L in patients with Parkinson's disease

INTRODUCTION

The European Quality of Life Questionnaire 5 level version (EQ-5D-5L) is a recently updated instrument to assess Health-Related Quality of Life (HRQoL) that has not been validated extensively. The main objective of this study was to evaluate the internal consistency and convergent validation of the EQ-5D-5L in a large sample of subjects with Parkinson's disease (PD).

METHODS

A cross-sectional study was carried out. Consecutive Mexican subjects with PD were included. HRQoL was assessed using the EQ-5D-5L and the PDQ-8. Validity of the EQ-5D-5L was assessed determining its association with clinical ratings of disease severity, as well as correlation with PDQ-8. Additionally, performance was evaluated along predefined groups based on clinical and demographic data of known determinants of quality of life.

RESULTS

A total of 585 patients were included for this study. A strong correlation was found between EQ-5D-5L index and PDQ-8 index (Spearman's correlation coefficient=-0.75; p<0.001). Correlation between EQ-5D-5L index and PDQ-8 index remained strong (-0.60 to -0.78; p values <0.001) through all predefined groups. EQ-5D-5L scored higher in those patients with dyskinesia, wearing off, freezing, postural instability, cognitive impairment or depressive mood (p values <0.001).

CONCLUSION

The EQ-5D-5L is a valid instrument for evaluating HRQoL in PD, performing adequately irrespective of heterogeneous clinical and demographic characteristics, and showing to be sensitive to features of advanced disease and treatment complications.

[Profile characterization of Parkinson's disease in Mexico: ReMePARK study]

INTRODUCTION

The Mexican Registry of Parkinson´s disease (ReMePARK) is nested within a multicentric cohort aimed to describe motor, non-motor, and genetic determinants of Parkinson's disease in Mexican patients.

MATERIAL AND METHODS

To date, clinical and demographic data from 1,083 subjects has been obtained. Here we present the demographic and clinical data of the current sample along with its comparison with international reports.

RESULTS

A total of 607 male and 476 female subjects with Parkinson's disease were included. The mean age of the patients was 64.7 ± 12.9 years. The time from onset of symptoms to diagnosis was 2.4 ± 2.6 years. About 34% of subjects had only elementary education. Of the subjects, 54.4% were under treatment with dopamine agonists.

CONCLUSION

Subjects with Parkinson's disease incorporated into ReMePARK are comparable with other international registries, with the exception of the years of formal education, time to diagnosis, and the use of dopamine agonists. The characterization of the Mexican population with Parkinson's disease will improve diagnosis and therapeutic management as well as define research efforts in this area. Finally, registry future directions are presented.