Frontal functions in depressed and nondepressed Parkinson's disease patients: impact of severity stages.

Severity of Parkinson's disease (PD) and frontal impairment are positively correlated. Testing frontal functions in depressed/nondepressed PD patients with different severity stages may reveal whether depression leads to this impairment. We aimed to relate severity of PD to frontal functional impairment and to test if negative stimuli/depressive symptoms interfered with frontal tasks. The Stroop test and the Emotional Stroop test were performed by 46 PD patients, 18 of whom were depressed. The Hoehn and Yahr scale assessed severity of the disease. We calculated the difference in seconds for each Stroop card and the interference index (C/D) between depressed and nondepressed patients sharing the same severity of disease. The differences among the groups (depressed and nondepressed) according to the severity of the disease (mild and moderate) were compared using the Mann-Whitney test. The depressed patients had a poorer performance on the test than the nondepressed PD patients, although the difference was not statistically significant. In conclusion, there is a clinically relevant but not statistically significant difference on the performance of frontal tasks between depressed and nondepressed PD patients. Neither depression nor the severity of the disease were determinant to the poorer performance on the Stroop and the Emotional Stroop tests.

Recognizing depression in patients with Parkinson's disease: accuracy and specificity of two depression rating scale.

This study aimed to find cut-off scores for the Montgomery-Asberg rating scale (MADRS) and the Beck depression inventory (BDI) that can relate to specific clinical diagnoses of depression in Parkinson s disease (PD). Mild and moderate PD patients (n=46) were evaluated for depression according to the DSM IV criteria. All patients were assessed with the MADRS and the BDI. A "receiver operating characteristics" (ROC) curve was obtained and the sensibility, specificity, positive and the negative predictive values were calculated for different cut-off scores of the MADRS and the BDI. The Kappa statistic was calculated for different cut-off scores to assess the agreement between the clinical judgment and both scales. Depression was present in 18 patients. MADRS cut-off scores of 6 and 10 showed Kappa 0.5 and 0.56, respectively. Specificity of cut-off score of 6 was 78.6% and of cut-off score of 10 was 96.4%. Kappa agreement of BDI cut-off scores of 10 and 18 were 0.36 and 0.62, respectively. Specificity was 60.7% for 10 and 92.9% for 18. Both rating scales show similar accuracy within the ROC curves (84.3% for MADRS and 79.7% for BDI). The MADRS and the BDI show a good accuracy and correlation to the clinical diagnosis when a cut-off score of 10 is used to MADRS and a cut-off score of 18 is used to BDI to recognize depression in mild to moderate PD patients. This may help clinicians to recognize depression in PD.

Recognizing depression in patients with Parkinson's disease: accuracy and specificity of two depression rating scale

Este estudo objetivou encontrar pontos de corte da escala de depressão de Montgomery-Asberg (MADRS) e inventário de depressão de Beck (IDB) que possam estar relacionados ao diagnóstico clínico específico de depressão na doença de Parkinson (DP). Os pacientes com DP leve e moderada (n= 46) foram avaliados para depressão de acordo com os critérios diagnósticos da DSM-IV. MADRS e IDB foram aplicadas em todos os pacientes. Uma curva "receiver operating characteristics" (ROC) foi obtida calculando-se sensibilidade, especificidade, valores preditivos positivo e negativo para diferentes pontos de corte da MADRS e IDB. O índice Kappa foi calculado verificando-se a concordância entre o julgamento clínico e, ambas as escalas em diferentes pontos de corte. A depressão estava presente em 18 pacientes. Os pontos de corte 6 e 10 da MADRS evidenciaram índice Kappa de 0,5 e 0, 56 respectivamente. A especificidade para o ponto de corte 6 foi 78.6% e para o ponto de corte 10 foi 96,4%. O índice Kappa para os pontos de corte 10 e 18 do IDB foi 0,36 e 0,62 respectivamente. A especificidade foi 60, 7% para o ponto de corte 10 e 92,9% para o 18. Ambas as escalas mostraram acurácia semelhante pelas curvas ROC (84,3% para MADRS e 79,7% para IDB). A MADRS e o IDB mostraram uma boa acurácia e correlação com o diagnóstico clínico quando o ponto de corte 10 foi utilizado para MADRS e o 18 para o IDB. A sugestão de tais pontos de corte tem por objetivo auxiliar aos clínicos no reconhecimento de depressão na DP leve e moderada.