Objective: To investigate the prevalence and clinical correlates of anxiety and depression in patients with Parkinson's disease (PD) and to examine the relationship between anxiety and depression and the quality of life (QOL).
Methods: One hundred and seventeen patients with PD completed the state-trait anxiety inventory (STAI), the beck depression inventory second edition (BDI-II), Starkstein's apathy scale (AS) and QOL battery. Hoehn and Yahr (HY) staging, the unified Parkinson's disease rating scale (UPDRS) and the mini-mental state examination (MMSE) were administered on the same day.
Results: Anxiety (STAI score ≥41 for men or ≥42 for women) was diagnosed in 55% of the patients and depression (BDI-II score ≥14) was diagnosed in 56% of the patients. Anxiety coexisted with depression in 41% of the patients, while depression without anxiety was observed in 15% of the patients and anxiety without depression was observed in 14% of the patients. The STAI score was found to be significantly correlated with the UPDRS (I, IV) and AS scores, whereas the BDI-II score was found to correlate with the HY stage and the UPDRS (I, III, IV) and AS scores. Both the STAI and BDI-II scores were found to negatively correlate with QOL. A multivariate analysis revealed that depression and anxiety are similarly associated with the PD specific QOL (PDQ-39), while motor severity, as judged by the HY stage and UPDRS III score, is not.
Conclusion: These findings indicate that recognizing anxiety and depression in patients with PD is important, since both conditions are commonly observed in patients with PD and are similarly associated with the QOL, independent of motor severity.