Impact of psychogenic movement disorders versus Parkinson's on disability, quality of life, and psychopathology

Patients with psychogenic movement disorders (PMD) often report severe impairment, yet the impact of PMD on disability and quality of life has not been examined. We compared 66 patients with PMD and 704 patients with Parkinson's disease (PD) on measures of disability (Older Americans Resources and Services Scale, OARS); quality of life (QOL; SF-12v2 Health Survey) and psychiatric symptornatology (Brief Symptom Inventory 18, BSI-18). On the total OARS, PMD and PD patients reported similar levels of disability (17.6 +/- 6.6, 19.8 +/- 10.9, P = 0.490 at best function and 24.1 +/- 11.2, 26.2 +/- 14.3, P = 0.497 at their worst function). PMD patients reported similar Physical Health QOL to PD patients (38.9 +/- 14.5, 39.8 +/- 11.6, P = 0.652) but worse mental health QOL (41.6 +/- 13.4 vs. 48.9 +/- 11.0, P < 0.001). On the BSI-18, PMD patients reported higher levels of distress on the Global Symptom Index (62.03 +/- 9.6 vs. 53.7 +/- 9.9, P < 0.001) and on Anxiety, Depression and Somatization subscales (PMD vs. PD scores: Anxiety 58.9 +/- 12.0 vs. 52.3 +/- 10.1, P < 0.001; Depression 58.8 +/- 11.9 vs. 51.3 +/- 10.3, P < 0.001; Somatization 60.5 +/- 11.0 vs. 54.7 +/- 8.7, P < 0.001). Thus, severity of disability reported by the PMD group was equal to that seen in a progressive neurodegenerative condition. Quality of life and mental health implications of PMD were also evident. PMD impacts several aspects of patient function and daily life. (c) 2007 Movement Disorder Society.