Proton Magnetic Resonance Spectroscopy Changes in Parkinson's Disease With and Without Psychosis.

BACKGROUND: Psychosis prevalence in Parkinson's disease is estimated at 8-30%. Proton magnetic resonance spectroscopy measures specific metabolites as markers of cell functioning. OBJECTIVE: To study N-acetyl-aspartate and glutamate levels in the caudate and putamen nuclei in subjects with Parkinson's disease with and without psychosis. METHODS: We included 20 non-demented Parkinson's disease patients with psychosis and 20 Parkinson's disease patients without psychosis matched for age, sex, disease duration, and levodopa equivalent daily dose, all attended at an academic medical center. Proton magnetic resonance spectroscopy scans were performed in a 3T GE whole-body scanner. RESULTS: Decreased glutamate levels scaled to creatine were found in the dorsal caudate (p = 0.005) and putamen (p = 0.007) of the Parkinson's disease psychosis group compared with the without psychosis group. Glutamate plus glutamine levels scaled to creatine and N-acetyl-aspartate levels scaled to creatine were also significantly reduced in the dorsal caudate of the Parkinson's disease with psychosis group (p = 0.018 and p = 0.011, respectively). No group differences were found for any of the other metabolites in the two regions of interest. CONCLUSIONS: Our findings suggest that decreased metabolite levels in specific brain areas may be implicated in the development of psychosis in Parkinson's disease.

[Anti-N-Methyl-D-aspartate receptor encephalitis (anti-NMDAR): a case report]. / Encefalitis por anticuerpos antirreceptor de N-metil-D-aspartato (anti-NMDAR): reporte de un caso.

Anti-N-methyl-D-aspartate receptor encephalitis (anti-NMDAR) is an autoimmune disorder characterized by neuropsychiatric symptoms, hyperkinetic movements, and even central hypoventilation. Anti-NMDAR encephalitis is a recently described disease, but is already considered one of the most frequent etiologies of noninfectious encephalitis. We report the case of 16-year-old man in which it the presence of anti-NMDAR antibodies in the absence of a neoplasm was identified. Disease course and gradual recovery, as well as a brief review of the syndrome, is presented. To our knowledge this is the first proven case of anti-NMDAR encephalitis in Mexico.

Comparing the accuracy of different smell identification tests in Parkinson's disease: relevance of cultural aspects.

OBJECTIVE: The aim of this study is to determine the usefulness of the University of Pennsylvania smell identification test (UPSIT), sniffin sticks (SS-16) and brief smell identification test (B-SIT) to assess smell identification in the Mexican population and its accuracy in discriminating subjects with Parkinson's disease (PD). METHODS: We included 199 nondemented PD subjects and 199 control subjects matched by gender. Smell identification was tested using the UPSIT and SS-16. Our group obtained B-SIT data from a previous report. RESULTS: The mean number of UPSIT items correctly identified by controls was 27.3±6; the PD group had a mean score of 19.4±6. UPSIT had a sensitivity of 82% with a specificity of 66% for a cut-off score of ≤25 for detection of PD. The mean number of SS-16 items correctly identified by controls was 10.3±2.2, while the PD group had 7.4±2.8 correct answers. For SS-16, sensitivity was 77.8% and specificity of 71.2% when using a cut-off value of ≤9. Lemon, turpentine and rose had an identification rate below the 25th percentile for all three tests. Odors with an identification rate above the 75th percentile include banana for all three tests, and gasoline, onion and chocolate for UPSIT and B-SIT. CONCLUSION: The sensitivity and specificity of the smell tests that were evaluated were lower in comparison to other published reports. Cultural biases and smell familiarity may influence the test results. The development of a true cross-culturally adapted smell identification test is warranted may improve test accuracy.

Impulse control and related disorders in Mexican Parkinson's disease patients.

BACKGROUND: Impulse control disorders (ICDs) are a relatively recent addition to the behavioral spectrum of PD-related non-motor symptoms. Social and economic factors may play a role on the ICD phenotype of PD patients. OBJECTIVE: The aim of this study is to determine the prevalence and characterize the clinical profile of ICDs in a sample of low-income, low-education PD patients with no social security benefits from a Latin American country. METHODS: We included 300 consecutive PD patients and 150 control subjects. The presence of ICD and related disorders was assessed using a structured interview. After the interview and neurological evaluation were concluded, all subjects completed the Questionnaire for Impulsive-compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS). RESULTS: Regarding ICDs and related disorders (hobbyism-punding), 25.6% (n = 77) of patients in the PD group and 16.6% (n = 25) in the control group fulfilled criteria for at least one ICD or related disorder (p = 0.032). There was a statistically significant difference in the QUIP-RS mean score between PD and control subjects (5.6 ± 9.7 and 2.7 ± 4.21, p = 0.001). The most common ICD was compulsive eating for both PD (8.6%) and control (2.6%) groups. CONCLUSIONS: The results of this study confirm that for this population, symptoms of an ICD are significantly more frequent in PD subjects than in control subjects. Nevertheless, socioeconomic differences may contribute to a lower overall frequency and distinct pattern of ICDs in PD patients compared with what has been reported in other countries.

[ApoE polymorphisms and dopaminergic replacement therapy in Parkinson's disease]. / Polimorfismos de apoE y reemplazo dopaminérgico en enfermedad de Parkinson.

BACKGROUND: The expression of apolipoprotein E (apoE) polymorphisms has been proposed as a risk factor for early development of psychotic symptoms in patients with Parkinson's disease. The association between apoE polymorphisms and motor complications is controversial. The aim was to determine the association between apoE polymorphisms and its allele frequency with the development of complications secondary to dopaminergic replacement therapy. METHODS: We evaluated 231 patients with the diagnosis of Parkinson's disease. The presence of motor complications secondary to treatment was determined by a neurologist, and the genotypification of apoE polymorphisms was performed. Descriptive statistics and chi-squared test were used. RESULTS: Genotype ?3/?3 was expressed in 80.5 % of the sample; there was no association between genotype or allele frequency of apoE polymorphisms and the development of psychosis or dyskinesia. Patients who expressed the ?2 allele showed a tendency to develop motor fluctuations, but without reaching statistical significance (p = 0.08). CONCLUSIONS: ApoE polymorphisms are not associated with the development of complications from dopaminergic replacement therapy.

INTRODUCCIÓN: se ha propuesto que la expresión de los polimorfismos de la apolipoproteína E (apoE) es un factor predisponente para el desarrollo temprano de psicosis en los pacientes con enfermedad de Parkinson. La relación entre el genotipo de la apoE y el desarrollo de complicaciones motoras es controvertida. El objetivo de esta investigación fue determinar la relación entre los polimorfismos de la apoE y su frecuencia alélica y el desarrollo de complicaciones secundarias al reemplazo dopaminérgico. MÉTODOS: se evaluaron 231 pacientes con diagnóstico de enfermedad de Parkinson. La presencia de complicaciones fue determinada por un neurólogo y se realizó la genotipificación de los polimorfismos de la apoE. Se utilizó la chi cuadrada para determinar la relación entre la presencia o ausencia de las complicaciones estudiadas y el genotipo de la apoE. RESULTADOS: se identificó el genotipe ?3/?3 en 80.5 % de la muestra. No existió relación entre el genotipo o la frecuencia alélica de los polimorfismos de la apoE y el desarrollo de psicosis o discinesias. Los pacientes que expresaron el alelo ?2 mostraron una tendencia al desarrollo de fluctuaciones, pero sin significación estadística (p = 0.08). CONCLUSIONES: los polimorfismos de la apoE no se relacionaron con el desarrollo de complicaciones derivadas del reemplazo dopaminérgico. El tratamiento de la enfermedad de Parkinson se basa principalmente en la administración de precursores de la dopamina (como la levodopa) o de agonistas dopaminérgicos.

Low specificity and sensitivity of smell identification testing for the diagnosis of Parkinson's disease.

OBJECTIVE: The aim of this study is to determine if the University of Pennsylvania's Smell Identification Test (UPSIT) is an accurate diagnostic tool for olfactory dysfunction in Parkinson's disease (PD). METHOD: We included 138 non-demented PD subjects and 175 control subjects matched by gender. Smell identification was tested using UPSIT. RESULTS: The mean number of UPSIT items correctly identified by controls was 27.52 ± 5.88; the mean score for PD subjects was 19.66 ± 6.08 (p=<0.001). UPSIT sensitivity was 79.7% with a specificity of 68.5% using a cut-off score of ≤ 25. The overall accuracy for the diagnosis of PD was of 75.3%. CONCLUSION: UPSIT accuracy and specificity were lower than what has been previously reported. Our data demonstrates that 17.5% of items of the UPSIT were not well identified by healthy controls. Further research of the identification of a truly cross-cultural test is warranted.

Low specificity and sensitivity of smell identification testing for the diagnosis of Parkinsons disease / Baixa sensibilidade e especificidade do teste de identificacao de odores para o diagnostico da doenca de Parkinson

Objective: The aim of this study is to determine if the University of Pennsylvania’s Smell Identification Test (UPSIT) is an accurate diagnostic tool for olfactory dysfunction in Parkinson’s disease (PD). Method: We included 138 non-demented PD subjects and 175 control subjects matched by gender. Smell identification was tested using UPSIT. Results: The mean number of UPSIT items correctly identified by controls was 27.52±5.88; the mean score for PD subjects was 19.66±6.08 (p=<0.001). UPSIT sensitivity was 79.7% with a specificity of 68.5% using a cut-off score of ≤25. The overall accuracy for the diagnosis of PD was of 75.3%. Conclusion: UPSIT accuracy and specificity were lower than what has been previously reported. Our data demonstrates that 17.5% of items of the UPSIT were not well identified by healthy controls. Further research of the identification of a truly cross-cultural test is warranted. .

Objetivo: O objetivo deste estudo é determinar se o University of Pennsylvania Smell Identification Test (UPSIT) é uma ferramenta diagnóstica útil para a caracterizar disfunção olfativa na doença de Parkinson (DP). Método: Foram incluídos 138 indivíduos não dementes assuntos PD e 175 indivíduos controle pareados por sexo. Identificação cheiro foi testada usando UPSIT. Resultados: O número médio de itens UPSIT corretamente identificados pelos controles foi de 27,52±5,88; para sujeitos com DP foi de 19,66±6,08 (p=<0,001). A sensibilidade do UPSIT foi de 79,7%, com especificidade de 68,5%, utilizando um ponto de corte de ≤25. A exatidão global para o diagnóstico de DP foi de 75,3%. Conclusão: A precisão e a especificidade do UPSIT foram menores do que o que foi relatado anteriormente. Nossos dados demonstram que 17,5% dos itens da UPSIT não foram adequadamente identificados pelos controles saudáveis. São necessárias outras pesquisas para a identificação de um teste verdadeiramente cross-cultural nessa área. .

Apathy and associated factors in Mexican patients with Parkinson's disease.

Apathy is one of the most common behavioral disturbances in Parkinson's disease (PD) with a reported prevalence of 17-51 %. Apathy has been associated with depression, cognitive deficits, and poor quality of life. The objective of this study was to determine the prevalence of apathy in Mexican subjects with PD and its correlation with clinical and demographic characteristics. A cross-sectional, descriptive, and analytic study was carried out. Consecutive subjects with PD attending the National Institute of Neurology and Neurosurgery in Mexico City were included. Demographic and other relevant clinical data were collected. The Apathy Scale was applied to all subjects. A cut-off score of ≥ 14 was used. A total of 241 non-demented patients (52.7 % male) were included. Apathy was found in 43 % of subjects. Lower body mass index, older age of PD onset, cognitive decline and disease severity were all related to apathy. The use of dopamine agonists or rasagiline was more common in patients with low apathy scores. Our results show that the prevalence of apathy in Mexican subjects with PD is similar to other reports.

[Time from motor symptoms onset to diagnosis of Parkinson's disease in Mexico]. / Tiempo desde el inicio de los síntomas motores hasta el diagnóstico de enfermedad de Parkinson (EP) en México.

INTRODUCTION: Parkinson's disease is characterized by a wide spectrum of motor and non-motor symptoms with an insidious onset. Identification of these symptoms by the patient as well as by the physician is determinant in order to achieve an early diagnosis. OBJECTIVE: To determine the time from motor symptoms onset to the diagnosis of Parkinson's disease and analyze the clinical and demographic factors related to it. MATERIAL AND METHODS: A cross-sectional study was carried out including subjects with Parkinson's disease seen during the 2011-2012 period and belonging to the Mexican National Parkinson's Registry. Time from symptom onset to the diagnosis was collected; its relation with demographic and clinical characteristics was assessed. RESULTS: A total of 1,062 subjects were included. Delay in diagnosis was 29.5 months. Predictive factors for a longer diagnostic delay were symptoms onset before 40 years of age (B: -0.350; p < 0.001) and a positive family history of Parkinson's disease (B: 0.224; p < 0.001). CONCLUSIONS: The diagnosis of Parkinson´s disease in Mexico is two and a half times greater than what has been reported for other countries.

[Profile characterization of Parkinson's disease in Mexico: ReMePARK study]. / Caracterización de la enfermedad de Parkinson en México: estudio ReMePARK.

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.