Mindy J. Katz

Validity of divided attention tasks in predicting falls in older individuals: A preliminary study

OBJECTIVES: Although cognitive impairment is known to be a major risk factor for falls in older individuals, the role of cognitive tests in predicting falls has not been established. Limited attentional resources may increase the risk for falls in older individuals. We examined the reliability and validity of divided attention tasks, walking while talking (WWT), in predicting falls.

Epidemiology of Gait Disorders in Community‐Residing Older Adults

OBJECTIVES: To study the epidemiology of gait disorders in community‐residing older adults and their association with death and institutionalization.

Leisure activities and the risk of amnestic mild cognitive impairment in the elderly

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.

Memory and mental status correlates of modified Braak staging

We assessed the relationships of performance on memory and mental status tests and neuropathologic stage of Alzheimers disease as defined by Braak and Braak in 29 patients from a prospective clinicopathologic series. We predicted that memory changes would occur at an earlier Braak stage than mental status changes. Staging was accomplished by matching the topographic distribution of neurofibrillary lesions detected with tau immunocytochemistry to the best fitting diagram published by Braak and Braak. Higher Braak stages were associated with decrements in performance on both memory and mental status tests. As predicted, memory performance declined from stages II to III and mental status did not decline until stages III to IV. The association between memory and Braak stage was unchanged after adjusting for neocortical senile plaques, whereas adjustments for Braak stage eliminated the association between cognitive functioning and amyloid burden. We conclude that Braak staging provides a useful summary of Alzheimers disease neuropathology, which is associated with both memory and mental status performance.

The relationship between specific cognitive functions and falls in aging

The current study examined the relationship between cognitive function and falls in older people who did not meet criteria for dementia or mild cognitive impairment (N = 172). To address limitations of previous research, the authors controlled for the confounding effects of gait measures and other risk factors by means of associations between cognitive function and falls. A neuropsychological test battery was submitted to factor analysis, yielding 3 orthogonal factors (Verbal IQ, Speed/Executive Attention, Memory). Single and recurrent falls within the last 12 months were evaluated. The authors hypothesized that Speed/Executive Attention would be associated with falls. Additionally, the authors assessed whether associations between different cognitive functions and falls varied depending on whether single or recurrent falls were examined. Multivariate logistic regressions showed that lower scores on Speed/Executive Attention were associated with increased risk of single and recurrent falls. Lower scores on Verbal IQ were related only to increased risk of recurrent falls. Memory was not associated with either single or recurrent falls. These findings are relevant to risk assessment and prevention of falls and point to possible shared neural substrates of cognitive and motor function.

Age-specific and sex-specific prevalence and incidence of mild cognitive impairment, dementia, and Alzheimer dementia in blacks and whites: a report from the Einstein Aging Study.

As the population ages, the need to characterize rates of cognitive impairment and dementia within demographic groups defined by age, sex, and race becomes increasingly important. There are limited data available on the prevalence and incidence of amnestic mild cognitive impairment (aMCI) and nonamnestic mild cognitive impairment (naMCI) from population-based studies. The Einstein Aging Study, a systematically recruited community-based cohort of 1944 adults aged 70 or older (1168 dementia free at baseline; mean age, 78.8 y; average follow-up, 3.9 y), provides the opportunity to examine the prevalence and incidence rates for dementia, Alzheimer dementia (AD), aMCI, and naMCI by demographic characteristics. Dementia prevalence was 6.5% (4.9% AD). Overall dementia incidence was 2.9/100 person-years (2.3/100 person-years for AD). Dementia and AD rates increased with age but did not differ by sex. Prevalence of aMCI was 11.6%, and naMCI prevalence was 9.9%. aMCI incidence was 3.8 and naMCI incidence was 3.9/100 person-years. Rates of aMCI increased significantly with age in men and in blacks; sex, education, and race were not significant risk factors. In contrast, naMCI incidence did not increase with age; however, blacks were at higher risk compared with whites, even when controlling for sex and education. Results highlight the public health significance of preclinical cognitive disease.

Screening for Dementia by Telephone Using the Memory Impairment Screen

Objectives: To develop and assess telephone‐based screening tests for dementia, especially Alzheimers disease (AD).

Chronic pain and obesity in elderly people: results from the Einstein aging study.

OBJECTIVES: To determine the prevalence of chronic pain in elderly people and its relationship with obesity and associated comorbidities and risk factors.

Epilepsy in Children with Mental Retardation: A Cohort Study

Summary: The cumulative risk of seizures and epilepsy was investigated in a prospectively identified cohort of 221 children with mental retardation (MR) born between 1951 and 1955 in Aberdeen, Scotland. By age 22 years, 33 (15%) had epilepsy. An additional 16 (7%) had had at least one seizure, but did not meet the criteria for epilepsy. The cumulative risk of epilepsy was 9, 11, 13, and 15% at 5, 10, 15, and 22 years, respectively. In children with MR and no associated disabilities, the cumulative risk of epilepsy was only 2.6, 3.2, 3.9, and 5.2% at 5, 10, 15, and 22 years. In children with MR and cerebral palsy (CP), the cumulative risk was 28, 31, and 38% at 5, 10, and 22 years. Children with a postnatal injury associated with MR had a cumulative risk of epilepsy of 53, 66, and 66% at 5, 10, and 15 years after the injury. By age 22 years, 39% had achieved 5‐year seizure‐free remission, including 56% of children with MR without associated disability, 47% of children with MR and CP, and 11% of children with a postnatal injury. We conclude that, in the absence of associated disability or postnatal injury, the risk of epilepsy in the retarded population is low. Epilepsy in this population also will frequently enter remission in later life.

Mechanisms of association between obesity and chronic pain in the elderly

&NA; Chronic pain is more common in the elderly and impairs functioning and quality of life. Though obesity, defined by body mass index (BMI), has been associated with pain prevalence among older adults, the mechanism of this association remains unclear. We examined components of the metabolic syndrome, insulin resistance, a marker of inflammation, and the presence of painful comorbidities as possible mediators of this association. Participants were 407 individuals aged ≥70 in the Einstein Aging Study. Chronic pain and pain over the last 3 months were defined using the Total Pain Index (TPI). Insulin resistance was modeled as fasting insulin, HOMA and QUICKI. High sensitivity C‐reactive protein was used as a marker of inflammation. Cross‐sectional logistic regression models were constructed to assess the associations of these factors with prevalent pain, adjusted for other known pain correlates. Prevalence of chronic pain was 52%. Of the clinical components of metabolic syndrome, central obesity was significantly associated with pain (OR 2.03, 95% CI 1.36–3.01). After adjustment for insulin resistance, inflammation, and pain‐related comorbidities, central obesity predicted higher TPI scores (OR 1.55, 95% CI 1.04–2.33) and nearly doubled the risk of chronic pain (OR 1.70, 95% CI 1.05–2.75). Central obesity is the metabolic syndrome component showing the strongest independent association with pain, and the relationship is not explained by markers of insulin resistance or inflammation, nor by the presence of osteoarthritis or neuropathy.