Although the informal caregiving role is associated with a range of stressors that are both chronic and severe, little is known concerning the acute physical and psychological effects of caregiving in the natural setting. This study evaluated the hemodynamic and psychological responses of five women identified as family caregivers who also worked outside the home and five matched working noncaregivers.
Subjects wore an ambulatory blood pressure monitor that recorded blood pressure and heart rate on an hourly basis throughout a one- to two-day period. They also completed hourly logs evaluating psychological, physical, and health-related variables through use of a preprogrammed pocket computer. Within- and between-group responses were compared in clinical, work, and postwork settings.
Caregivers and noncaregivers showed comparable ambulatory blood pressure levels in the clinic and work settings. However, in contrast to noncaregivers, who showed the expected decrease in blood pressure level upon leaving the work setting (p values < .03), caregivers demonstrated a significant increase in systolic blood pressure levels following work when they were in the presence of the care recipient (p < .0002). The differences observed in blood pressure responses between the two groups were similarly reflected in the patterns of affective response recorded in the work and postwork settings.
The results provide initial evidence of the acute iatrogenic effects of caregiving on physiological as well as psychological response systems.
This study describes characteristics and predictors of survival in an outpatient Geriatric Evaluation and Management (GEM) population.
Prospective evaluation and longitudinal follow-up of consecutive patients (N = 636) seen in a GEM Clinic between January 1986 and September 1991.
The typical patient was 78.4 years of age, White, female (73%), unmarried (66%), and living with a spouse or relative (47%). Although two-thirds were demented, most were independent in Activities of Daily Living (ADL) and partially dependent in Instrumental Activities of Daily Living (IADL). Subjects were followed for an average of 25 months. In bivariate analysis, IADL was the strongest predictor of survival (O.R. = 4.4). Higher ADL, better cognitive status, lower comorbid illness, and lack of recent hospitalization were also predictive of survival. In stepwise logistic regression, only IADL (O.R. = 4.2) and comorbid illness (O.R. = 1.5) predicted survival. In Kaplan-Meier Lifetable Analysis, survival at two years was 91% in the least dependent IADL group while survival was 75% in the most dependent group. Comorbid illness was the only factor that improved prediction of survival above that seen with IADL alone. When subjects are stratified by both function and illness, mortality was 36% in the ill and disabled group and 8% in those of high function and limited illness.
IADL and comorbid illness scores offer a means of stratifying subjects for risk of death and may be useful in evaluating and comparing mortality experience in outpatient GEM and control populations. Stratification may increase the likelihood that studies aimed at improving survival will detect a difference resulting from the intervention.
Methods. The prospective cohort was examined at baseline and eight years later. A total of 2,222 men and 2,677 women age 20–79 years at baseline were included. Analyses were performed in 15-year age groups, and persons with cardiovascular disease or cancer during the observation period were excluded.
Results. In longitudinal analyses, body mass index (BMI) and plasma total cholesterol levels of each rose in concert among younger age groups, whereas levels declined in older individuals. Mean levels of bmi and total cholesterol peaked at a later age in women than in men. The corresponding changes in HDL-C were negative at all ages, and greater declines were seen in the elderly. A decrease in plasma total cholesterol was highly associated with greater age and a decrease in body mass index over the study interval, whereas the decline in HDL-C was proportional to change in body mass index. These changes remained significant after adjustment for baseline age and change in alcohol intake, cigarette consumption, diuretic use, and oral estrogen use.
Conclusions. The rise in plasma total cholesterol among apparently healthy young men and women and its fall in the elderly are significantly associated with similar trends for obesity. The key determinants of a decline in HDL-C are an increase in obesity and advancing age itself. A decline in total cholesterol and in HDL-C is particularly common among the elderly, and it can be expected to occur without specific dietary or pharmacologic intervention
]]>Poor balance in older persons increases the risk of injurious falls during daily activities. Functional base of support (FBOS), the anterior-posterior proportion of foot length used in maximal sustained forward and backward leaning, tests controlled center of mass movement, a component of balance required in daily activities. The purpose of this study was to examine the relationship between FBOS and age and establish the reliability of this measure.
Subjects were 113 community-dwelling men and women, ages 20 to 91. FBOS, measured on a force platform, is the difference between mean center of pressure location during sustained forward and backward leaning, divided by foot length. Forward lean (FL), backward lean (BL), and average sway distance during normal standing (STAND SWAY) and while leaning (FBOS SWAY) were also measured.
Mean FBOS was .60 ± .07 in subjects under age 60, and .42 ± 12 in subjects 60 and older. FBOS remained constant in younger subjects; beyond age 60, FBOS declined about 16% per decade and was more variable. FL and BL also declined with age, remaining 66% and 34% of FBOS, respectively. STAND SWAY and FBOS SWAY were significantly correlated with each other, but not with FBOS.
FBOS is a reliable measure and is decreased on average in older persons. This decrease is not related to increased sway while standing or leaning. FBOS is a simple force platform test that has potential as a measure of change in this dimension of balance and as a predictor of falls risk in older persons
In addition to their value in assessing pulmonary health and disease, spirometric variables have been shown to be powerful predictors of time until death in aging populations. The sources of variability in these spirometric values are consequently of relevance to basic gerontological research, and also of potential value in clinical application. The objective of this study was to estimate genetic and environmental sources of variance in pulmonary function.
The study involved 230 Swedish twin pairs (mean age = 64.9 years), of which number 37 monozygotic (MZ) pairs and 72 dizygotic (DZ) pairs had been separated and reared apart. Comparing these groups to the 57 MZ and 64 DZ pairs reared together permits stronger interpretation than that of conventional twin studies. Measures of vital capacity (VC) and forced expiratory volume in one second (FEV1) were residualized for height, age, sex, and tobacco consumption in pack-years.
Maximum likelihood analyses of VC and FEV1gave heritability estimates of .48 and .67, respectively. Age effects were explored both by dividing the sample into two cohorts, respectively above and below 65 years, and by moving interval analysis. In the two-cohort analysis, heritabilities were somewhat higher for the older cohort than the younger cohort for FEV. The opposite was true for VC: heritability was lower in the older cohort, and there was evidence for a shared rearing environmental effect for this group. Moving interval analysis suggests these differences are gradual rather than saltatory. There were no gender differences in parameter estimates.
Genetic factors account tor between one-half and two-thirds of the variability in pulmonary function. There is a suggestion of age differences in the relative importance of genetic and environmental influences.
Methods. The research was based on a longitudinal study of a cohort of 1,056 Hong Kong Chinese men and women aged 70 and above. Among the 476 nonsmoking women at baseline, 374 with weight measurements both at baseline and at 24 months follow-up were included in the study. Proportional hazards analysis with adjustment for age and other physical and social factors was used to estimate the relative risk of mortality of the higher body mass index groups in relation to the lowest body mass index group and between the weight change groups.
Results. Women belonging to the middle fertile of body mass index distribution had the lowest mortality. Those with a weight loss of more than 2 kg over the first 24 months follow-up had five times the risk of mortality at 40 months, even after adjusting for health and social conditions and baseline body mass index.
Conclusion. The results suggest that both the initial body weight and weight change during the follow-up period are important considerations in the study of the association between body weight and mortality.
]]>Methods. Various organizational and performance characteristics of GEMS were entered in a data base derived from a piloted questionnaire and administrative records. Basic criteria from consensus reports were used to classify and compare =standard= and =nonstandard= GEMS. The criteria covered performance of assessment, team structure, patient selection, GEM location, and treatment functions. We analyzed the effect of GEM type and other factors on length of stay and placement. Reasons for closure of GEMS inactive in 1991 were recovered, and GEMS active in 1991 but later closed are described.
Results. As of 1991, 41 of 73 GEMS were classified as standard, and 32 nonstandard. Standard compared to nonstandard GEMS had shorter stays (25.4 vs 69.9 days; p < .001), higher home discharge rates (63.4% vs 40% p < .001), and lower nursing home placement rates (19.1% vs40.3%p < .001). Eleven hospitals had closed their programs by 1991. By 1993, 6 additional GEMS had closed; all were nonstandard in 1991.
Conclusions. Most VA GEMS are organized according to basic consensus standards, and appear to be discharging most patients back to the community after reasonably short stays. However, various resource constraints are common, apparently reflected in nonstandard organization and GEM closure. Additional work is needed to monitor GEM proliferation, implementation, and performance in and out of the VA system.
]]>Body composition differs between young and old females, although the magnitude of these age-related changes remains uncertain. This uncertainty persists because methodology applied in earlier studies required assumptions that may be age-dependent and also because studies included young and old subjects who differed substantially in body size and health status.
To resolve these earlier concerns we examined components at the atomic, molecular, cellular, tissue-system, and whole body levels of body composition in 19 weight-and height-matched pairs of young (age 19-35 yrs) and old (age ≥ 65 yrs) healthy white females. Isotope dilution, dual photon, whole-body counting, hydrodensitometry, and anthropometric methods were used either alone or in combination to produce multicomponent models.
Old females had significantly more fat, greater truncal skinfolds and circumferences, and significantly less fatfree body mass (FFM), total body potassium (TBK), total body water (TBW), and bone mineral than did their young matched counterparts. Skeletal muscle mass was less in the old females, although the magnitude of the difference from young females varied between the three indices examined. The main assumptions (i.e., TBW/FFM = 0.73 kg/kg and density of FFM = 1.100 g/cc) which the widely used two-compartment TBW and hydrodensitometry methods are based on were not significantly different in young and old females. In contrast, the main assumed steady-state value for the twocompartment TBK method (TBK/FFM = 64.2 mmol/kg) was significantly lower (p < .001) in the old females.
New approaches thus allow for a critical reexamination of body composition in elderly subjects, and these methods also give new insight into less complex widely used body composition techniques.
Comprehensive geriatric assessment (CGA) in ambulatory settings can be effective only if patients who need this intervention are willing to participate in the evaluation and follow the indicated therapy.
To learn whether older persons' health beliefs and perceptions influence participation in ambulatory-based CGA, we studied subjects who failed a screening assessment offered through a community-based outreach program and were deemed appropriate for CGA. All subjects were interviewed in person following a structured sequence including questions from the RAND Current Health (CH) and Health Worry/Concern (HWC) scales, the Health Locus Of Control Scale (HLC), and scales developed to measure health risks and perceived benefits of geriatric assessment.
In univariate analysis, the following variables were associated with refusal to participate in CGA status at the p ≤ .05 level: increased worry on hwc and higher scores on three new scales constructed to measure global health risk (GHR), perceived global health benefits (PGHB), and perceived specific health benefits (PSHB). For GHR, higher scores indicate greater risk; for PGHB and PSHB, higher scores indicate greater perceived benefit. In multivariate analysis, only educational level, GHR, PGHB, and PSHB scores were independently predictive of refuser status. Correlations with other established health perceptions scales provided support that global health risk and perceived global and specific health benefits are unique constructs. Furthermore, high scores on these scales predicted participation in health improvement programs.
Patients' beliefs about perceived risk and benefit can be measured and predict willingness to participate in ambulatory-based CGA.
While cognitive and functional deficits are the hallmark of Alzheimer's disease (AD), loss of social function (and the dependence this implies) is also critical, especially in early stages of disease. Little attention has been directed to this facet of dementing disease. We describe a scale for assessing dependency in AD and present a baseline profile of dependency in a cohort of AD patients.
In a study of the predictors of the course of AD, 233 patients in early stages of disease (modified MMS 5* 30) were assessed. Psychometric properties of the dependence scale were established. To validate the scale, dependence scores at baseline were correlated with a series of measures assessing cognition and function. The course of dependency over 18 months of follow-up was also analyzed.
The scale shows adequate reliability (test-retest, intraclass correlation). Dependence stage was related to other measures of disease severity. Scalogram analysis shows that the dependence scale is consistent with the course of functional loss established for dementing disease. Prospective data indicate sensitivity of the scale to disease progression.
Dependency is a distinct, measurable component of dementing disease and should be considered an important outcome in studies of AD.
In late stages of dementia of the alzheimer type (DAT), most scales measuring only cognitive or functional deficits lose their sensitivity to detect further disease progression.
By combining ratings of cognitive (speech, eye contact) and functional deficits (dressing, eating, ambulation) with occurrence of pathological symptoms (sleep-wake cycle disturbance, muscle rigidity/contractures), a scale was developed (BANS-S) which does not lose its sensitivity until the patient reaches a vegetative state. BANS-S was tested on three Special Care Dementia Units.
Data from 74 patients with the clinical diagnosis of DAT indicated that BANS-S has good reliability and reproducibility. BANS-S scores correlated with scores of Mini-mental State Examination, Katz ADL, Test for Severe Impairment, and Language Assessment. In 25 patients with the diagnosis of DAT confirmed by autopsy, BANS-S scores determined within 3 months of death correlated with density of neurofibrillary tangles in CA2 and CA3 areas of the hippocampus.
BANS-S may be a useful tool for the evaluation of different treatment strategies in severe DAT and for the correlation of clinical and pathological findings
Falls during walking are often triggered when a foot contacts an obstacle in its path. Yet little is known about the ability of individuals of any age to successfully negotiate obstacles, especially under time-critical conditions.
The gait of 24 young and 24 old healthy adults (mean ages 23 and 73 years) was studied as they approached and tried to avoid stepping on a band of light, not knowing when or where it might appear on an 8 m-long walkway. This virtual obstacle was placed at the predicted location of the next footfall with available response times (ART) before heel strike that were varied randomly in 50 ms increments from 200 to 450 ms. In addition, their gait was observed as-they stepped over a fixed virtual obstacle and over an obstacle that appeared with approximately a 1000 ms ART.
The old had an increased risk of obstacle contact while negotiating obstacles under time-critical conditions (p = .082). Mean rates-of-success (RS) in obstacle avoidance for the young ranged from .205 at a 200 ms ART to .969 at a 450 ms ART. Corresponding mean RS for the old were .157 and .920. Lower extremity simple reaction time (SRT) tests made under static conditions showed that the mean SRT of the old were approximately 80 ms longer than those of the young. Regression analyses suggested that the old in fact would have needed only 30 ms additional ART to achieve rs equal to that of the young for obstacles appearing with ART from 300 to 450 ms.
Reductions in ART significantly decreased RS. Delays as small as 50 or 100 ms in observing or reacting to obstacles in real-life situations may significantly lower the rate of success that subjects of any age have in avoiding them. Age differences in SRT do not always reliably indicate age differences in obstacle avoidance under time-critical situations.
To reassess conflicting findings in earlier studies on the effect of aging on smooth pursuit and saccadic eye movements, we compared visual tracking in a large number of elderly normal subjects aged 75 to 93 years and a group of young adults aged 18 to 43 years.
Saccades and smooth pursuit were induced by a laser target projected onto a screen. Eye movements were recorded with electrooculography and analyzed with a digital computer.
Smooth pursuit gain was significantly decreased at all target velocities in the older subjects, and the difference between young and old increased with increasing target velocity and acceleration. Peak saccade velocity was significantly slower for amplitudes exceeding 20°, and saccadic reaction times were prolonged in older subjects compared with younger subjects. Mean saccade accuracy was not significantly different between age groups. Within tests, variability increased with aging for smooth pursuit, saccadic reaction time, and saccadic accuracy measurements.
The increased intratest variability in older subjects probably resulted from nonspecific changes in alertness and attention commonly occurring with aging, whereas the decreased gain of smooth pursuit and saccades with increasing stimulus magnitude most likely resulted from age-related neural degeneration in specific visuomotor pathways.
Our driving population is aging and faces increased risk for injury and death from motor vehicle crashes. Clinicians are often asked to judge the driving safety of their patients without adequate guidelines. This article describes the development of a systematic performance-based road test for measuring driving skills of elderly drivers and its correlation with cognitive measures.
This was a prospective, masked, observational study in which a driving instructor's global scores ("criterion standard") and cognitive test scores were correlated with research driving scores created by two independent research raters sitting in the back seat of the car during each driving test. A convenience sample of 30 licensed drivers with a broad range of cognitive skills, over age 60, were studied on a closed course and in traffic.
Statistically significant correlations were observed between the "criterion standard" and closed course scores (r = .35, p< .05) and between the "criterion standard" and in-traffic scores (r = .64, p= .01). Significant correlations were obtained between in-traffic and cognitive test scores, e.g., Mini-Mental State Exam (r = .72, p< .01). Inter-rater reliability on the closed course was .84 and on the in-traffic component was .74. Internal consistency for the closed course was .78 and for in-traffic was .89.
This study documented the safety, reliability, and validity of a systematic road test for elderly drivers with a range of cognitive skills. Larger studies are needed to determine the cognitive factors that independently predict driving performance.
Prior studies indicate that older women fall more often than men although there is no evidence of genderbased balance differences. Using a force platform, we measured the effects of restricted sensory input and support surface movement to detect gender differences in balance.
Healthy, elderly community dwellers (N = 234, mean age = 76 ± 5 years, 52% female) were administered the following perturbations on the balance platform: The platform and/or visual surround were fixed or tilted proportionally to the subject's sway with the eyes open or closed, forward or backward horizontal translations, and toes-up and toes-down rotations.
Gender-based balance differences were not present during quiet standing, or when the support surface or visual input were manipulated separately. Women swayed and lost their balance more than men when the surface was sway-referenced while vision was compromised, but by the third trial their sway control was comparable to the men. Women also initially lost their balance more frequently than men during toes-up and -down rotations, and compared to men continued to lose their balance more often during repeated toes-up rotations. Finally, women developed less angular momentum than men in response to forward platform rotations.
Elderly women show impairments of balance when simultaneously deprived of visual and somatosensory inputs or during a backwards destabilization. Since there is little evidence for a CNS source for such gender differences, biomechanical origins (e.g., dorsiflexion strength and range of motion) are a more likely cause. Limited postural control of women under conditions stressing balance may explain their greater frequency of falling
A unique contribution of a comprehensive outpatient geriatric assessment is its focus on social and safety issues in the frail elderly. The impact of such programs depends on the caregiver and/or patient complying with safety and social recommendations offered by the assessment team. Compliance in this setting has not been previously described.
A telephone survey was conducted of self-reported compliance in 124 frail geriatric patients with a high prevalence of dementia 3—21 months after completing a comprehensive geriatric assessment program at the University of California, San Diego, Medical Center.
The social and safety recommendations constituted 52.8% of all the recommendations offered. The overall compliance rate (total number of safety and social recommendations followed/total number offered x 100) was 50.2% (95% CI: 43.7—56.6). Highest compliance was achieved with recommendations to complete a prior directive for health care (80.6%) and to wear a medic-alert bracelet (57.5%). Patients complied poorly with recommendations to change a living situation (36.2%). Analysis of variance showed compliance to increase with time between the assessment and survey. Stratifying for time, we found higher compliance in patients with greater impairment in functional or cognitive status. Most noncompliance was due to disagreement with the recommendations offered or failure to implement acceptable recommendations.
Compliance with social and safety recommendations offered in a comprehensive geriatric assessment program approximates compliance observed in other clinical settings. In this setting compliance increases over time. When controlled for time, impairment in functional or cognitive status is associated with greater compliance.
Chronic cognitive impairment is a major problem in U.S. Nursing homes, yet traditional assessment systems in most facilities included only limited information on cognitive status. Following the Congressional mandate in the Omnibus Reconciliation act of 1987 (OBRA '87), U.S. nursing homes, now complete the Minimum Data Set (MDS), a standardized, comprehensive assessment of each resident's functional, medical, psychosocial, and cognitive status. We designed a Cognitive Performance Scale (CPS) that uses MDS data to assign residents into easily understood cognitive performance categories.
Information was drawn from three data sets, including two multistate data sets constructed for the Health Care Financing Administration. The prevalence and reliability of the MDS cognitive performance variables were established when assessed by trained nursing personnel. Five selected MDS items were combined to create the single, functionally meaningful seven-category hierarchical Cognitive Performance Scale.
The CPS scale corresponded closely with scores generated by the Mini-Mental State Examination and the Test for Severe Impairment, nursing judgments of disorientation, and neurological diagnoses of Alzheimer's disease and other dementias.
The new CPS provides a functional view of cognitive performance, using readily available MDS data. It should prove useful to clinicians and investigators using the MDS to determine a resident's cognitive assets.
Vasopressin has been shown to improve electrophysiological signs of cognitive stimulus processing in young human subjects. This study compared the effects of arginine vasopressin (AVP) on central nervous stimulus processing in old and young mentally healthy subjects. To assess aspects of cognitive stimulus processing, event-related potentials (ERPs) were recorded.
A total of 22 old and 28 young subjects were tested on two subsequent days. Substances were administered intranasally 22, 12, and 1 hour(s) prior to experimental sessions. Prior to the first session, all subjects received placebo. Prior to the second session, 11 of the elderly and 15 of the young subjects received AVP (3 x 10 IU in each nostril) while the remaining subjects again received placebo. The study was held double blind. The subjects performed an auditory "oddball" task consisting of rare target tones (requiring a button press response) interspersed throughout a sequence of frequent standard tones while an electroencephalogram was recorded.
Differences between young and aged subjects were more pronounced for ERPs to targets than standard pips. Latencies of the N2 and P3 waves of the ERP to targets were significantly prolonged, and the P3 amplitude was diminished in the elderly subjects (p < .01). N2 amplitude was enhanced in both age groups by vasopressin (p < .05). However, AVP treatment significantly enlarged the N2-P3 difference amplitude only in young subjects.
The results indicate that AVP improves ERP signs of stimulus processing associated with attentional mechanisms. However, the ERP signs of age-related cognitive impairment remained unimproved after AVP.
The purpose of the study was to determine if bone mineral density (BMD) in elderly Chinese subjects was associated with indices of calcium metabolism (parathyroid hormone, vitamin D), osteocalcin, and other nonbiochemical factors.
104 men (mean age 74 ± 6 yrs) and 213 women (mean age 76 ± 8 yrs) with no previous history of fractures were recruited from old age hostels and community centers. BMD was measured with dual energy X-ray absorptiometry.
BMD in both sexes was associated with body mass index (BMI), arm circumference, and skinfold thicknesses. Additionally, in women there was a positive association with grip strength and load-bearing activities, a negative association with age in all sites except for the lumbar spine, and negative associations with indices of bone turnover (osteocalcin, urinary hydroxyproline/creatinine and calcium/creatinine ratios). After adjusting for BMI, women with hypertension or taking antihypertensive drugs had higher mean BMD at the lumbar spine. Multivariate analyses showed that only BMI predicted BMD in men, while age, BMI, and arm circumference were predictors of BMD in women.
Indices of calcium metabolism were not correlated with BMD in this elderly Chinese population, suggesting that the age-related rise in parathyroid hormone and reduced intestinal absorption of calcium may not be important factors in determining BMD in elderly Chinese men and women.