Dementia in Parkinson's disease: a Brazilian sample

Abstract

To determine the prevalence of dementia associated with Parkinson's disease (PD-D) in a Brazilian sample adopting clinical and diagnostic procedures recommended by the Movement Disorders Society (MDS). Sixty-seven patients were consecutively submitted to neurological, neuropsychological and functional examinations. PD-D was established according to MDS clinical criteria (Level II) and clinical procedures for PD-D (Level I) and prevalence rate was compared between the levels adopted. Ten patients (14.9%) were diagnosed as demented by Level I criteria whereas sixteen (23.8%) were diagnosed based on Level II criteria. Level I criteria had low sensitivity in detecting PD-D (31.25%), but greater specificity (90.19). The PD-D group had significantly worse performance on all neuropsychological tests, were older (p<0.001), had an older age of onset ofdisease (p<0.01), had lower educational level (p<0.02) and had higher scores on functional scales. Current age (p=0.046) and Hoehn & Yahr score (p=0.048) were predictors for developing PD-D. Key words: Parkinson's disease, Parkinson's disease dementia, neuropsychological evaluation.Prevalência da demência associada à doença de Parkinson: uma amostra brasileira RESUMO Determinar a prevalência de demência associada à doença de Parkinson (D-DP) em uma amostra brasileira, adotando os procedimentos diagnósticos e clínicos recomendados pela Movement Disorders Society (MDS). Sessenta e sete pacientes foram submetidos à avaliação neurológica, neuropsicológica e funcional. D-DP foi estabelecida de acordo com os procedimentos (Nível I) e critérios clínicos propostos pela MDS (Nível II) e a prevalência de D-DP foi comparada entre os níveis adotados. A prevalência de D-DP encontrada pelo Nível I e II, foi de 14,9% e 23,8%, respectivamente. O Nível I apresentou baixa sensibilidade em detectar D-DP (31,25%), porém, mostrou alta especificidade (90,19%). O grupo D-DP teve desempenho significativamente inferior em todas tarefas neuropsicológicas, eram mais velhos (p<0,001), mais velhos ao início da doença (p<0,01), menos escolarizados (p<0,02) e elevados escores nas tarefas funcionais. Idade atual (p=0,046) e escore no Hoehn & Yahr (p=0,048) foram apontados como preditores do desenvolvimento de D-DP. Palavras-Chave: doença de Parkinson, demência associada à doença de Parkinson, avaliação neuropsicológica. Correspondence

Comparison of the use of screening tools for evaluating cognitive impairment in patients with Parkinson's disease

“… 5 , 13 Moreover, the MMSE is believed to be relatively insensitive for mild cognitive deficits. 13 , 16 , 28 , 33 …”

Addenbrooke's Cognitive Examination-Revised is accurate for detecting dementia in Parkinson's disease patients with low educational level

“…Comparison between diagnostic criteria (Level II) and clinical procedures (Level I) for PD dementia has revealed that Level II had good discrimination in the detection of PD dementia, whereas Level I criteria had lower sensitivity (31.25%), greater specificity (90.19%), and positive and negative predictive values of 50% and 82.45%, in the detection of PD dementia. 6 The lower sensitivity with Level I criteria could be related to the adoption of an MMSE cut-off value of less than 26. This suggests that the MMSE cut-off value proposed by MDS Level I criteria could be affected by educational level, and not considering educational level could lead to a false-negative PD dementia diagnosis.…”

“… 3 The point prevalence of dementia associated with Parkinson's disease (PDD) has been estimated to range from 20% to 40%. 4 - 6 This wide variability is due to several factors, including the assessment method used, with a higher prevalence reported in studies using comprehensive neuropsychological instruments compared with those screening global cognitive function, 7 and the proportion of patients with multiple risk factors for dementia development. 8 …”

Diagnóstico e manejo da demência da doença de Parkinson e demência com corpos de Lewy: recomendações do Departamento Científico de Neurologia Cognitiva e do Envelhecimento da Academia Brasileira de Neurologia

“…A ocorrência de demência na DP é comum e sua prevalência aumenta com o tempo de doença, variando de 23% nos primeiros anos da doença a 80% com mais de 15 anos de sintomas [15][16][17] . O conhecimento de quais fatores de risco estão associados à ocorrência de demência em pacientes com DP e as características que diferenciam os pacientes com DCL de outras etiologias são essenciais para um diagnóstico precoce e uma terapia mais adequada.…”