Frances M. Yang

Delirium accelerates cognitive decline in Alzheimer disease.

Objective: To examine the impact of delirium on the trajectory of cognitive function in a cohort of patients with Alzheimer disease (AD). Methods: A secondary analysis of data collected from a large prospective cohort, the Massachusetts Alzheimer’s Disease Research Center’s patient registry, examined cognitive performance over time in patients who developed (n = 72) or did not develop (n = 336) delirium during the course of their illnesses. Cognitive performance was measured by change in score on the Information-Memory-Concentration (IMC) subtest of the Blessed Dementia Rating Scale. Delirium was identified using a previously validated chart review method. Using linear mixed regression models, rates of cognitive change were calculated, controlling for age, sex, education, comorbid medical diagnoses, family history of dementia, dementia severity score, and duration of symptoms before diagnosis. Results: A significant acceleration in the slope of cognitive decline occurs following an episode of delirium. Among patients who developed delirium, the average decline at baseline for performance on the IMC was 2.5 points per year, but after an episode of delirium there was further decline to an average of 4.9 points per year (p = 0.001). Across groups, the rate of change in IMC score occurred about three times faster in those who had delirium compared to those who did not. Conclusions: Delirium can accelerate the trajectory of cognitive decline in patients with Alzheimer disease (AD). The information from this study provides the foundation for future randomized intervention studies to determine whether prevention of delirium might ameliorate or delay cognitive decline in patients with AD.

Intergenerational Support to Aging Parents The Role of Norms and Needs

This investigation examines how norms of filial responsibility influence adult children to provide social support to their aging parents. Relying on intergenerational solidarity and social capital theories, the authors hypothesize that filial responsibility as a latent resource is more strongly converted into support when (a) the parent experiences increased need and (b) the child in question is a daughter. Using data from 488 adult children in the Longitudinal Study of Generations, the authors examine change in support provided between 1997 and 2000. Declining health of either parent increases the strength with which filial norms predisposed children to provide support. The conversion of filial norms into support is stronger among daughters than among sons but only toward mothers. Results are discussed in terms of the contingent linkage between latent and manifest functions and the persistence of gender role differentiation in the modern family.

Delirium: An independent predictor of functional decline after cardiac surgery

OBJECTIVES: To determine whether patients who developed delirium after cardiac surgery were at risk of functional decline.

Persistent Delirium Predicts Greater Mortality

OBJECTIVES: To examine the association between persistent delirium and 1‐year mortality in newly admitted post‐acute care (PAC) facility patients with delirium who were followed regardless of residence.

PHENOMENOLOGICAL SUBTYPES OF DELIRIUM IN OLDER PERSONS: PATTERNS, PREVALENCE, AND PROGNOSIS

BACKGROUND Delirium is an acute confusional state that is common, preventable, and life-threatening. OBJECTIVE The authors investigated the phenomenology of delirium severity as measured with the Memorial Delirium Assessment Scale among 441 older patients (age 65 and older) admitted with delirium in post-acute care. METHODS Using latent class analysis, they identified four classes of psychomotor-severity subtypes of delirium: 1) hypoactive/mild; 2) hypoactive/severe; 3) mixed, with hyperactive features/severe; and 4) normal/mild. RESULTS Among those with dementia (N=166), the hypoactive/mild class was associated with a higher risk of mortality. Among those without dementia (N=275), greater severity was associated with mortality, regardless of psychomotor features, when compared with the normal/mild class. CONCLUSION The data suggest that instruments measuring delirium severity and psychomotor features provide important prognostic information and should be integrated into the assessment of delirium.

Hypertension, White Matter Hyperintensities, and Concurrent Impairments in Mobility, Cognition, and Mood The Cardiovascular Health Study

Background— Our objective was to investigate the association between hypertension and concurrent impairments in mobility, cognition, and mood; the role of brain white matter hyperintensities in mediating this association; and the impact of these impairments on disability and mortality in elderly hypertensive individuals. Methods and Results— —Blood pressure, gait speed, digit symbol substitution test, and the Center for Epidemiological Studies Depression Scale were measured yearly (1992–1999) on 4700 participants in the Cardiovascular Health Study (age: 74.7, 58% women, 17% blacks, 68% hypertension, 3600 had brain magnetic resonance imaging in 1992–1993, survival data 1992–2005). Using latent profile analysis at baseline, we found that 498 (11%) subjects had concurrent impairments and 3086 (66%) were intact on all 3 measures. Between 1992 and 1999, 651 (21%) became impaired in all 3 domains. Hypertensive individuals were more likely to be impaired at baseline (odds ratio 1.23, 95% confidence interval 1.04 to 1.42, P=0.01) and become impaired during the follow-up (hazard ratio=1.3, 95% confidence interval 1.02 to 1.66, P=0.037). A greater degree of white matter hyperintensities was associated with impairments in the 3 domains (P=0.007) and mediated the association with hypertension (P=0.19 for hypertension after adjusting for white matter hyperintensities in the model, 21% hazard ratio change). Impairments in the 3 domains increased subsequent disability with hypertension (P<0.0001). Hypertension mortality also was increased in those impaired (compared with unimpaired hypertensive individuals: HR=1.10, 95% confidence interval 1.04 to 1.17, P=0.004). Conclusions— Hypertension increases the risk of concurrent impairments in mobility, cognition, and mood, which increases disability and mortality. This association is mediated in part by microvascular brain injury.

Hospitalization in Community-Dwelling Persons with Alzheimer’s Disease: Frequency and Causes

OBJECTIVES: To examine the rates of and risk factors for acute hospitalization in a prospective cohort of older community‐dwelling patients with Alzheimers disease (AD).

A Novel Aging Phenotype of Slow Gait, Impaired Executive Function, and Depressive Symptoms: Relationship to Blood Pressure and Other Cardiovascular Risks

BACKGROUND Our objectives were to investigate the existence of a group of nondemented elderly individuals who simultaneously have impairments in cognition, mobility, and mood, and to examine the association between being a member of this group and elevated blood pressure and other cardiovascular conditions. METHODS The Maintenance of Balance, Independent Living, Intellect, and Zest in the Elderly of Boston study is an ongoing prospective observational study of community-dwelling individuals. We analyzed the cross-sectional data collected at baseline (N=580, mean age=77.8 years, 64% women, 14% African American, mean Mini-Mental State Examination=27.2). Using latent profile analysis, we investigated the existence of a group of elderly participants with impairments in executive function (Trail Making Test Part B [TMT-B]), gait speed (two 4-m walk tests), and depressive symptoms (Center for Epidemiological Studies-Depression scale [CES-D]). RESULTS We identified a group (n=99 [17%]) with prolonged TMT-B, slow gait speed, and high CES-D scores. This group did not exist when we used a memory measure. Hypertension (p=.001), diabetes (p=.0002), congestive heart failure (p=.006), stroke (p=.005), and higher Framingham cardiovascular risk score (p=.0001) were associated with an increased likelihood of being a member in this group. This association with elevated systolic and pulse pressure, and stroke remained significant after multiple covariate adjustments. CONCLUSIONS There exists a group of elderly individuals in whom poor executive function, slow gait speed, and depressive symptoms occur simultaneously. Memory measures did not identify such a grouping. Elevated blood pressure and other cardiovascular diseases are independently associated with being a member of this group. Assessing these domains is an important part of the evaluation of the elderly patients with high vascular risk.

Aging, Brain Disease, and Reserve: Implications for Delirium

Cognitive and brain reserve are well studied in the context of age-associated cognitive impairment and dementia. However, there is a paucity of research that examines the role of cognitive or brain reserve in delirium. Indicators (or proxy measures) of cognitive or brain reserve (such as brain size, education, and activities) pose challenges in the context of the long prodromal phase of Alzheimer disease but are diminished in the context of delirium, which is of acute onset. This article provides a review of original articles on cognitive and brain reserve across many conditions affecting the central nervous system, with a focus on delirium. The authors review current definitions of reserve. The authors identify indicators for reserve used in earlier studies and discuss these indicators in the context of delirium. The authors highlight future research directions to move the field ahead. Reserve may be a potentially modifiable characteristic. Studying the role of reserve in delirium can advance prevention strategies for delirium and may advance knowledge of reserve and its role in aging and neuropsychiatric disease generally.

Telephone Interview for Cognitive Status: Creating a crosswalk with the Mini-Mental State Examination

Brief cognitive screening measures are valuable tools for both research and clinical applications. The most widely used instrument, the Mini‐Mental State Examination (MMSE), is limited in that it must be administered face‐to‐face, cannot be used in participants with visual or motor impairments, and is protected by copyright. Screening instruments such as the Telephone Interview for Cognitive Status (TICS) were developed to provide a valid alternative, with comparable cut‐point scores to rate global cognitive function.