ABSTRACT
OBJECTIVE: To test the cognitive reserve hypothesis by examining the effect of education on memory decline during the preclinical course of dementia. BACKGROUND: Low education is a well known risk factor for Alzheimer disease (AD). Persons destined to develop AD experience an accelerated rate of decline in cognitive ability, particularly in memory. The cognitive reserve hypothesis predicts that persons with greater education begin to experience acceleration in cognitive decline closer to the time of diagnosis than persons with lower reserve, but that their rate of decline is more rapid after the time of acceleration due to increased disease burden. METHODS: We studied the influence of education on rates of memory decline as measured by the Buschke Selective Reminding Test in 117 participants with incident dementia in the Bronx Aging Study. Subjects had detailed cognitive assessments at entry and at annual follow-up visits. We estimated the time at which the rate of decline begins to accelerate (the change point), and the pre- and post-acceleration rates of decline, from the longitudinal data using a change point model. RESULTS: Each additional year of formal education delayed the time of accelerated decline on the Buschke Selective Reminding Test by 0.21 years. Post-acceleration, the rate of memory decline was increased by 0.10 points per year for each year of additional formal education. CONCLUSIONS: As predicted by the cognitive reserve hypothesis, higher education delays the onset of accelerated cognitive decline; once it begins it is more rapid in persons with more education.
Subject(s)
Dementia/diagnosis , Educational Status , Memory/physiology , Age Factors , Aged , Aged, 80 and over , Dementia/psychology , Disease Progression , Female , Humans , Male , Neuropsychological TestsABSTRACT
OBJECTIVE: To study the influence of leisure activity participation on risk of development of amnestic mild cognitive impairment (aMCI). METHODS: The authors examined the relationship between baseline level of participation in leisure activities and risk of aMCI in a prospective cohort of 437 community-residing subjects older than 75 years, initially free of dementia or aMCI, using Cox analysis adjusted for age, sex, education, and chronic illnesses. The authors derived Cognitive and Physical Activity Scales based on frequency of participation in individual activities. RESULTS: Over a median follow-up of 5.6 years, 58 subjects had development of aMCI. A one-point increase on the Cognitive (hazard ratio [HR] 0.95, 95% CI 0.91 to 0.99) but not Physical Activities Scale (HR 0.97, 95% CI 0.93 to 1.01) was associated with lower risk of aMCI. Subjects with Cognitive Activity scores in the highest (HR 0.46, 95% CI 0.24 to 0.91) and middle thirds (HR 0.52, 95% CI 0.29 to 0.96) had a lower risk of aMCI compared with subjects in the lowest third. The association persisted even after excluding subjects who converted to dementia within 2 years of meeting criteria for aMCI. CONCLUSIONS: Cognitive activity participation is associated with lower risk of development of amnestic mild cognitive impairment, even after excluding individuals at early stages of dementia.
Subject(s)
Amnesia/epidemiology , Amnesia/psychology , Cognition Disorders/epidemiology , Cognition Disorders/psychology , Leisure Activities/psychology , Aged , Aged, 80 and over , Amnesia/prevention & control , Cognition Disorders/prevention & control , Cohort Studies , Female , Follow-Up Studies , Humans , Male , Neuropsychological Tests , Prospective Studies , Risk FactorsABSTRACT
Clinicians often encounter patients whose neurologic attacks appear to cluster. In a daily diary study, the authors explored whether clustering is a true phenomenon in epilepsy and can be identified in the clinical setting. Nearly half the subjects experienced at least one episode of three or more seizures in 24 hours; 20% also met a statistical clustering criterion. Utilizing the clinical definition of clustering should identify all seizure clusterers, and false positives can be determined with diary data.
Subject(s)
Epilepsy/diagnosis , Adult , Chronic Disease , Cohort Studies , Diagnosis, Differential , Epilepsy/physiopathology , False Positive Reactions , Female , Humans , Male , Medical Records , Neurologic Examination , Recurrence , Space-Time Clustering , Statistical Distributions , Time FactorsABSTRACT
There is some evidence of retroviral infection in ALS. A randomized, double-blind, placebo-controlled trial of indinavir in ALS was performed to assess safety and efficacy trends. Nephrolithiasis and gastrointestinal side effects were frequent with indinavir treatment. Group differences in the rate of decline were not significant between the groups for the ALS Functional Rating Scale (p = 0.36) or for the secondary variables. The toxicity and negative efficacy trends discourage further indinavir trials in ALS.
