Intrusion Errors and Progression of Cognitive Deficits in Older Adults with Mild Cognitive Impairment and PreMCI States.

INTRODUCTION: Among persons with amnestic mild cognitive impairment (aMCI), intrusion errors on subscales that measure proactive semantic interference (PSI) may be among the earliest behavioral markers of elevated Alzheimer's disease brain pathology. While there has been considerable cross-sectional work in the area, it is presently unknown whether semantic intrusion errors are predictive of progression of cognitive impairment in aMCI or PreMCI (not cognitively normal but not meeting full criteria for MCI). METHODS: This study examined the extent to which the percentage of semantic intrusion errors (PIE) based on total responses on a novel cognitive stress test, the Loewenstein-Acevedo Scales for Semantic Interference and Learning (LASSI-L), could predict clinical/cognitive outcomes over an average 26-month period in older adults initially diagnosed with aMCI, PreMCI, and normal cognition. RESULTS: On the LASSI-L subscale sensitive to PSI, a PIE cut point of 44% intrusion errors distinguished between those at-risk individuals with PreMCI who progressed to MCI over time compared to individuals with PreMCI who reverted to normal on longitudinal follow-up. Importantly, PIE was able to accurately predict 83.3% of aMCI individuals who later progressed to dementia. DISCUSSION: These preliminary findings indicate that PIE on LASSI-L subscales that measure PSI may be a useful predictor of clinical progression overtime in at-risk older adults.

Utility of Plasma Neurofilament Light in the 1Florida Alzheimer's Disease Research Center (ADRC).

BACKGROUND: Plasma NfL (pNfL) levels are elevated in many neurological disorders. However, the utility of pNfL in a clinical setting has not been established. OBJECTIVE: In a cohort of diverse older participants, we examined: 1) the association of pNfL to age, sex, Hispanic ethnicity, diagnosis, and structural and amyloid imaging biomarkers; and 2) its association to baseline and longitudinal cognitive and functional performance. METHODS: 309 subjects were classified at baseline as cognitively normal (CN) or with cognitive impairment. Most subjects had structural MRI and amyloid PET scans. The most frequent etiological diagnosis was Alzheimer's disease (AD), but other neurological and neuropsychiatric disorders were also represented. We assessed the relationship of pNfL to cognitive and functional status, primary etiology, imaging biomarkers, and to cognitive and functional decline. RESULTS: pNfL increased with age, degree of hippocampal atrophy, and amyloid load, and was higher in females among CN subjects, but was not associated with Hispanic ethnicity. Compared to CN subjects, pNfL was elevated among those with AD or FTLD, but not those with neuropsychiatric or other disorders. Hippocampal atrophy, amyloid positivity and higher pNfL levels each added unique variance in predicting greater functional impairment on the CDR-SB at baseline. Higher baseline pNfL levels also predicted greater cognitive and functional decline after accounting for hippocampal atrophy and memory scores at baseline. CONCLUSION: pNfL may have a complementary and supportive role to brain imaging and cognitive testing in a memory disorder evaluation, although its diagnostic sensitivity and specificity as a stand-alone measure is modest. In the absence of expensive neuroimaging tests, pNfL could be used for differentiating neurodegenerative disease from neuropsychiatric disorders.

La pastoral de los cuerpos: pobreza, género y asistencia hospitalaria en Puerto Rico, 1812-1823 / The pastoral of the bodies: poverty, gender, and hospital care in Puerto Rico, 1812-1823

En este artículo se analizan los primeros intentos realizados por el Estado para implementar la beneficencia pública en Puerto Rico. Se argumenta que los liberales lucharon por adelantar sus políticas en favor de la población desposeída, pero que sus acciones se vieron limitadas por las dificultades que encontraron en la Isla, entre ellas la falta de las instituciones de caridad. En los dos primeros periodos constitucionales (1812-1814 y 1820-1823) se intentó actuar en favor de todos los pobres, pero solo se logró atender a los enfermos pobres en los hospitales de la ciudad de San Juan. En el desarrollo del artículo se muestra que durante el siglo XIX importó mucho el género para ingresar a los hospitales: en el primer periodo constitucional solamente se asistieron a los hombres en el Hospital Militar; las mujeres fueron atendidas en el segundo periodo constitucional, cuando el Estado consiguió administrar el Hospital de Pobres. A pesar de la intermitencia entre los proyectos políticos liberales y conservadores, se dieron los primeros pasos para comenzar a asistir a los enfermos puertorriqueños pobres en los hospitales de la ciudad

This article analyses the State's first attempt to implement public assistance in Puerto Rico. It is argued that liberals fought to advance their policies in order to favor the underprivileged population, but that their actions were limited by the difficulties encountered in the island, the lack of charities being one of them. During the first two constitutional periods (1812-1814 and 1820-1823,) an attempt was made to assist all of the underprivileged people, but only the sick at hospitals in the city of San Juan, were able to receive assistance. Throughout the article, it is demonstrated that during the XIX Century, gender played an important role when being admitted to a hospital: during the first constitutional period, only males received assistance at the Military Hospital; women received assistance during the second constitutional period, once the State was able to oversee the Hospital for the Underprivileged. In spite of the intermittence between the liberal and conservative political policies, the first steps to begin assisting sick and underprivileged Puerto Ricans in the city's hospitals were given

A novel method of evaluating semantic intrusion errors to distinguish between amyloid positive and negative groups on the Alzheimer's disease continuum.

BACKGROUND: The development and validation of clinical outcome measures to detect early cognitive decline associated with Alzheimer's disease (AD) biomarkers is imperative. Semantic intrusions on the Loewenstein Acevedo Scales of Semantic Interference and Learning (LASSI-L) has outperformed widely used cognitive measures as an early correlate of elevated brain amyloid in prodromal AD and has distinguished those with amnestic mild cognitive impairment (aMCI) and high amyloid load from aMCI attributable to other non-AD conditions. METHODS: Since intrusion errors on memory tasks vary widely, we employed a novel method that accounts for the percentage of intrusion errors (PIE) in relation to total responses. Individuals with either high or low amyloid load across the spectrum of aMCI and dementia and amyloid negative cognitively normal older adults (CN) were studied. RESULTS: Mean PIE on indices sensitive to proactive semantic interference (PSI) and failure to recover from proactive semantic interference (frPSI) could distinguish amyloid positive from amyloid negative aMCI and dementia groups. Number of correct responses alone, while able to differentiate the different diagnostic groups, did not differentiate amyloid positive aMCI from their counterparts without amyloid pathology. CONCLUSIONS: PIE, a novel and sensitive index of early memory dysfunction, demonstrated high levels of sensitivity and specificity in differentiating CN from amyloid positive persons with preclinical AD. Mean levels of PIE are higher for amyloid positive aMCI and dementia participants relative to their amyloid negative counterparts.