Long-term risks of death and institutionalization of elderly people in relation to deficit accumulation at age 70

OBJECTIVES: To measure relative fitness and frailty in older people without specific frailty instruments and to relate that measurement to long-term health outcomes. DESIGN: Retrospective cohort studies. SETTING: Two population-based studies of people aged approximately 70 at baseline and followed up to 10 years (in the Canadian Study of Health and Aging (CSHA)) or 26 years in the Gothenburg H-70 cohort study. PARTICIPANTS: Nine hundred sixty-two men and 1,178 women. MEASUREMENTS: Deficit accumulation (the exposure) was counted using self-reported (CSHA) or clinically designated (H-70) symptoms, signs, diseases, and disabilities. Relative fitness and frailty were measured in relation to the degree of deficit accumulation evaluated in four quartiles, representing those most fit to those most frail. The items that made up the frailty index were selected randomly without replacement in 1,000 iterations. The outcomes were risks of death or residential long-term care. RESULTS: Worse frailty, however measured, was associated with worse survival; the Kaplan-Meier curves of random iterations of the frailty definition showed virtually no interquartile overlap for mortality. For any given level of frailty, men died younger than women. Worse frailty was also associated with a higher risk of institutionalization. CONCLUSION: Frailty appears to be a robust concept that is readily operationalized, with the risk of adverse outcomes being largely established by age 70.     

Orthostatic hypotension (OH) and mortality in relation to age, blood pressure and frailty

Systolic hypertension and OH, as with many other deficits, accumulate with age. This deficit accumulation results in frailty: enhanced vulnerability to adverse outcomes. This study evaluated OH in relation to age, frailty, systolic hypertension, and mortality. In the population-based Canadian Study of Health and Aging second clinical examination, complete data were available on 1347 people, mean age=83.3 (SD=6.4)years. A frailty index (FI) was calculated from a 52-item Comprehensive Geriatric Assessment (CGA), yielding an FI-CGA from 0 (no deficits) to 1.0 (52 deficits). The mean change in blood pressure from lying to standing was 7.3±15.6 mmHg (range +94 to -60). In total, 239 people (17.7%) had OH (change >20 mmHg systolic or >10 mmHg diastolic). Mean systolic blood pressure was higher (155.8±23.3 mmHg) in people with OH than in those without (141.4±23 mmHg), as was the FI-CGA (0.18 vs. 0.16). OH increased with frailty and systolic hypertension, but not age. Unadjusted, OH was associated with an increased risk of death (relative risk=1.21, 95% confidence interval 1.19-1.23). Adjusted for frailty, this result was not significant. OH may be a marker of the system dysregulation seen in frailty, but as a state variable is a less powerful marker of vulnerability than is the FI-CGA.     

Physiological Redundancy in Older Adults in Relation to the Change with Age in the Slope of a Frailty Index

OBJECTIVES: To test the proposition, using routinely available clinical data, that deficit accumulation results in loss of redundancy. In keeping with the reliability theory of aging, this would be quantitated by attenuation in the slope of a Frailty Index (FI) with age. The more deficits, the less steep the slope and the less redundancy. DESIGN: Cross‐sectional analysis of a prospective cohort study, with 5‐year mortality data. SETTING: The clinical sample of the second wave of the Canadian Study of Health and Aging. PARTICIPANTS: Two thousand three hundred five people aged 70 and older at baseline. MEASUREMENTS: A FI based on data used for a Comprehensive Geriatric Assessment (CGA), the slope of the relationship between age and the FI‐CGA, the limit value of the FI‐CGA, mortality. RESULTS: An age‐invariant limit to deficit accumulation was demonstrated; the observed 99% limit was 0.66. At the 25th percentile of deficit accumulation (FI‐CGA ～0.18), the slope of the FI‐CGA in relation to age was 0.044 (range 0.038–0.049). When deficits had increased to 75% of the maximum value (FI‐CGA ～0.52), the slope fell to 0.021 (range 0.016–0.027). By the 85th percentile (FI‐CGA ～0.6), the slope had become statistically indistinguishable from 0. CONCLUSION: As predicted by the reliability theory of aging, the rate of deficit accumulation slows with increasing frailty. A FI derived from data routinely collected as part of a CGA can in this way quantify loss of redundancy in older adults. Quantifying loss of redundancy can aid clinical decision‐making; its application to individual prognostication in clinical samples warrants further evaluation.     

Prevalence and 10‐Year Outcomes of Frailty in Older Adults in Relation to Deficit Accumulation

OBJECTIVES: To evaluate the prevalence and 10‐year outcomes of frailty in older adults in relation to deficit accumulation. DESIGN: Prospective cohort study. SETTING: The National Population Health Survey of Canada, with frailty estimated at baseline (1994/95) and mortality follow‐up to 2004/05. PARTICIPANTS: Community‐dwelling older adults (N=2,740, 60.8% women) aged 65 to 102 from 10 Canadian provinces. During the 10‐year follow‐up, 1,208 died. MEASUREMENTS: Self‐reported health information was used to construct a frailty index (Frailty Index) as a proportion of deficits accumulated in individuals. The main outcome measure was mortality. RESULTS: The prevalence of frailty increased with age in men and women (correlation coefficient=0.955–0.994, P<.001). The Frailty Index estimated that 622 (22.7%, 95% confidence interval (CI)=21.0–24.4%) of the sample was frail. Frailty was more common in women (25.3%, 95% CI=23.2–27.5%) than in men (18.6%, 95% CI=15.9–21.3%). For those aged 85 and older, the Frailty Index identified 39.1% (95% CI=31.3–46.9%) of men as frail, compared with 45.1% (95% CI=39.7–50.5%) of women. Frailty significantly increased the risk of death, with an age‐ and sex‐adjusted hazard ratio for the Frailty Index of 1.57 (95% CI=1.41–1.74). CONCLUSION: The prevalence of frailty increases with age and at any age lessens survival. The Frailty Index approach readily identifies frail people at risk of death, presumably because of its use of multiple health deficits in multidimensional domains.     

Frailty defined by deficit accumulation and geriatric medicine defined by frailty

As nonreplicative cells age, they commonly accumulate subcellular deficits that can compromise function. As people age, they too experience problems that can accumulate. As deficits (symptoms, signs, illnesses, disabilities) accumulate, people become more susceptible to adverse health outcomes, including worse health and even death. This state of increased risk of adverse health outcomes is indistinguishable from the idea of frailty, so deficit accumulation represents another way to define frailty. Counting deficits not only allows grades of frailty to be discerned but also provides insights into the complex problems of older adults. This process is potentially useful to geriatricians who need to be experts in managing complexity. A key to managing complexity is through instruments such as a comprehensive geriatric assessment, which can serve as the basis for routine clinical estimation of an individual's degree of frailty. Understanding people and their needs as deficits accumulate is an exciting challenge for clinical research on frailty and its management by geriatricians.     

The rate of aging: the rate of deficit accumulation does not change over the adult life span

People age at different rates. We have proposed that rates of aging can be quantified by the rate at which individuals accumulate health deficits. Earlier estimates, using cross-sectional analyses suggested that deficits accumulated exponentially, at an annual rate of 3.5 %. Here, we estimate the rate of deficit accumulation using longitudinal data from the Canadian National Population Health Survey. By analyzing age-specific trajectories of deficit accumulation in people aged 20 years and over (n = 13,668) followed biannually for 16 years, we found that the longitudinal average annual rate of deficit accumulation was 4.5 % (±0.75 %). This estimate was notably stable during the adult life span. The corresponding average doubling time in the number of deficits was 15.4 (95 % CI 14.82–16.03) years, roughly 30 % less than we had reported from the cross-sectional analysis. Earlier work also established that the average number of deficits accumulated by individuals (N), equals the product of the intensity of environmental stresses (λ) causing damage to the organism, by the average recovery time (W). At the individual level, changes in deficit accumulation can be attributed to both changes in environmental stresses and changes in recovery time. By contrast, at the population level, changes in the number of deficits are proportional to the changes in recovery time. In consequence, we propose here that the average recovery time, W doubles approximately every 15.4 years, independently of age. Such changes quantify the increase of vulnerability to stressors as people age that gives rise to increasing risk of frailty, disability and death. That deficit accumulation will, on average, double twice between ages 50 and 80 highlights the importance of health in middle age on late life outcomes.     

Improvement and decline in health status from late middle age: modeling age-related changes in deficit accumulation

In a prospective multi-panel cohort study, we investigated how, from late middle age, individuals' health status improves or declines. In the Canadian National Population Health Survey, transition probabilities between different health states were estimated for 4330 people (58.8% women) aged 55+ at baseline over 2-year intervals from 1994 to 2000. Health status was defined by a deficit count, using 33 health-related variables combined in a frailty index. For each time interval, the chance of accumulating deficits increased linearly with the number of deficits. Older survivors (aged 70-85) showed a slightly lower chance of stability or improvement (52%; 95% confidence interval 50-54%) compared with those in late middle age (56%; 54-58%). Changes in health states can be described with high accuracy (R2=0.92) by a modified Poisson distribution, using four parameters: the background odds of accumulating additional deficits, the chance of incurring more or fewer deficits, given the existing number, and the corresponding probabilities of dying. An age-invariant limit to deficit accumulation was observed at 22 deficits. From late middle age, transitions in health states occur with a regularity that is easily modeled. Improvements in health can occur at any age. At all ages, there is a limit to deficit accumulation.     

Frailty index to predict all-cause mortality in Thai community-dwelling older population: A result from a National Health Examination Survey cohort

BackgroundFrailty is a clinical state of increased vulnerability from aging-associated decline. We aimed to determine if a Thai Frailty Index predicted all-cause mortality in community-dwelling older Thais when accounting for age, gender and socioeconomic status.MethodsData of 8195 subjects aged 60 years and over from the Fourth Thai National Health Examination Survey were used to create the Thai Frailty Index by calculating the ratio of accumulated deficits using a cut-off point of 0.25 to define frailty. The associations were explored using Cox proportional hazard models.ResultsThe mean age of participants was 69.2 years (SD 6.8). The prevalence of frailty was 22.1%. The Thai Frailty Index significantly predicted mortality (hazard ratio = 2.34, 95% CI 2.10–2.61, p < 0.001). The association between frailty and mortality was stronger in males (hazard ratio = 2.71, 95% CI 2.33–3.16). Higher wealth status had a protective effect among non-frail older adults but not among frail ones.ConclusionsIn community-dwelling older Thai adults, the Thai Frailty Index demonstrated a high prevalence of frailty and predicted mortality. Frail older Thai adults did not earn the protective effect of reducing mortality with higher socioeconomic status. Maintaining health rather than accumulating wealth may be better for a longer healthier life for older people in middle income countries.     

The estimation of relative fitness and frailty in community-dwelling older adults using self-report data

BACKGROUND: While on average health declines with age, it also becomes more variable with age. As a consequence of this marked variability, it becomes more important as people age to have a means of summarizing health status, but how precisely to do so remains controversial. We developed one measure of health status, personal biological age, from a frailty index. The index itself is a count of deficits derived, in the first instance, from a clinical database. In our earlier investigations, personal biological age demonstrated a strong relationship with 6-year survival. Here we extend this approach to self-reported data. METHODS: This is a secondary analysis of community-dwelling people aged 65 years and older (n = 9008) in the Canadian Study of Health and Aging. The frailty index was calculated from 40 self-reported variables, representing symptoms, attitudes, illnesses, and function. Personal biological age was estimated for each individual as the age corresponding to the mean chronological age for the index value. Individual frailty (and the related construct of fitness) was calculated as the difference between chronological and personal biological age. RESULTS: The frailty index showed, on average, an exponential increase with age at an average rate of 3% per year. Although women, on average, demonstrate more frailty than men of the same chronological age, their survival chances are greater. The frailty index strongly correlated (Pearson r =.992 for women and.955 for men) with survival. CONCLUSIONS: A frailty index, based on self-report data, can be used as a tool for capturing heterogeneity in the health status of older adults.     

Prevalence, attributes, and outcomes of fitness and frailty in community-dwelling older adults: report from the Canadian study of health and aging

BACKGROUND: Frailty and fitness are important attributes of older persons, but population samples of their prevalence, attributes, and outcomes are limited. METHODS: The authors report data from the community-dwelling sample (n = 9008) of the Canadian Study of Health and Aging, a representative, 5-year prospective cohort study. Fitness and frailty were determined by self-reported exercise and function level and testing of cognition. RESULTS: Among the community-dwelling elderly population, 171 per 1000 were very fit and 12 per 1000 were very frail. Frailty increased with age, so that by age 85 years and older, 44 per 1000 were very frail. The risk for adverse health outcomes increased markedly with frailty: Compared with older adults who exercise, those who were moderately or severely frail had a relative risk for institutionalization of 8.6 (95% confidence interval, 4.9 to 15.2) and for death of 7.3 (95% confidence interval, 4.7 to 11.4). These risks persist after adjustments for age, sex, comorbid conditions, and poor self-rated health. At all ages, men reported higher levels of exercise and less frailty compared with women. Decreased fitness and increased frailty were also associated with poor self-ratings of health (42% in the most frail vs 7% in the most fit), more comorbid illnesses (6 vs 3), and more social isolation (34% vs 29%). CONCLUSIONS: Fitness and frailty form a continuum and predict survival. Exercise influences survival, even in old age. Relative fitness and frailty can be determined quickly in a clinical setting, are potentially useful markers of the risk for adverse health outcomes, and add value to traditional medical assessments that focus on diagnoses.     

Transitions in frailty status in older adults in relation to mobility: a multistate modeling approach employing a deficit count

OBJECTIVES: To investigate how changes in frailty status and mortality risk relate to baseline frailty state, mobility performance, age, and sex. DESIGN: Cohort study. SETTING: The Yale Precipitating Events Project, New Haven, Connecticut. PARTICIPANTS: Seven hundred fifty‐four community‐dwelling people aged 70 and older at baseline followed up at 18, 36, and 54 months. MEASUREMENTS: Frailty status, assessed at 18‐month intervals, was defined using a frailty index (FI) as the number of deficits in 36 health variables. Mobility was defined as time in seconds on the rapid gait test, in which participants walked back and forth over a 20‐foot course as quickly as possible. Multistate transition probabilities were calculated with baseline frailty, mobility, age, and sex estimated using Poisson and logistic regressions in survivors and those who died, respectively. RESULTS: In multivariable analyses, baseline frailty status and age were significantly associated with changes in frailty status and risk of death, whereas mobility was significantly associated with the frailty but not with mortality. At all values of the FI, participants with better mobility were more likely than those with poor mobility to remain stable or to improve. For example, at 54 months, 20.6% (95% confidence interval (CI)=16–25.2) of participants with poor mobility had the same or fewer deficits, compared with 32.4% (95% CI=27.9–36.9) of those with better mobility. CONCLUSION: A multistate transition model effectively measured the probability of change in frailty status and risk of death. Mobility, age, and baseline frailty were significant factors in frailty state transitions.     

The impact of frailty and delirium on mortality in older inpatients

Background: delirium and frailty are common among hospitalised older people but delirium is often missed and frailty considered difficult to measure in clinical practice. Objective: to explore the relationship between delirium and frailty in older inpatients and determine their impact on survival. Design and setting: the prospective cohort study of 273 patients aged ≥75 years. Measures: patients were screened for delirium at presentation and on alternate days throughout their hospital stay. Frailty status was measured by an index of accumulated deficits (FI), giving a potential score from 0 (no deficits) to 1.0 (all 33 deficits), with 0.25 used as the cut-off between 'fit' and 'frail'. Results: delirium was detected in 102 patients (mean FI: 0.33) and excluded in 171 (mean FI: 0.18) (P?相似文献   

Evaluation of a frailty index based on a comprehensive geriatric assessment in a population based study of elderly Canadians

BACKGROUND AND AIMS: Objectives were to develop a frailty index (FI) based on a standard comprehensive geriatric assessment (CGA) derived from a clinical examination; to assess the validity of the FI-CGA and to compare its precision with other frailty measures. METHODS: DESIGN: Secondary analysis of a prospective cohort study, with five-year follow-up data. SETTING: Second phase of the Canadian Study of Health and Aging (CSHA-2); clinical examinations were performed in clinics, nursing homes, and patients' homes. PARTICIPANTS: People selected (as either cognitively impaired cases or unimpaired controls) to receive the CSHA-2 clinical examination (n = 2305; women = 1431). MEASUREMENTS: Clinical and performance-based measures and diagnostic data were extracted to correspond to the 10 impairment domains and the single comorbidity domain of a CGA. The proportion of deficits accumulated in each domain was calculated to yield the FI-CGA. The FI-CGA was validated and its predictive ability compared with other frailty measures. RESULTS: Within the seven grades of fitness/frailty identified, subjects with greater frailty were older, less educated, and more likely to be women. The FI-CGA correlated highly with a previously validated, empirically-derived frailty index (r = 0.76). Frailty was associated with higher risk of death (for each increment in frailty, the hazard ratio, adjusted for age, sex and education, was 1.23 (95% CI 1.18-1.29) and institutionalization (HR 1.20; 1.10-1.32). CONCLUSIONS: In a population survey, the FI-CGA is a valid means of quantifying frailty from routinely collected data.     

Disability and co-morbidity in relation to frailty: how much do they overlap?

The purpose of this study was to examine the association of disability and co-morbidity with frailty in older adults. 2305 participants aged 65+ from the second wave of the Canadian Study of Health and Aging (CSHA), a prospective population-based cohort study, comprised the study sample. Following a standard procedure, two different frailty index (FI) measures were constructed from 37 deficits by dividing the recorded deficits by the total number of measures. One version excluded disability and co-morbidity items, the other included them. Time to death was measured for up to five years. Frailty was defined using either the frailty phenotype or a cut-point applied to each FI. Of people defined as frail using the frailty phenotype, 15/416 (3.6%) experienced neither disability nor co-morbidity. Using 0.25 as the cut-point score for the FI (without disability/co-morbidity) resulted in 101/1176 (8.6%) frail participants that had neither disability nor co-morbidity. Activities of daily living (ADL) limitations and co-morbidities occurred more often among people with the highest levels of frailty. The first ADLs to become impaired with increasing frailty were bathing, managing medication, and cooking with more than 25% of older adults with a FI score (without disability/co-morbidity) >0.22 experiencing dependency on them. The hazard ratio (HR) per 0.1 increase in FI score was 1.25 (95% CI: 1.20-1.30) when disability and co-morbidity were included in the index and 1.21 (1.16-1.25) when they were not included. In conclusion, disability and co-morbidity greatly overlap with other deficits that might be used to define frailty and add to their ability to predict mortality.     

Frailty and survival of older Chinese adults in urban and rural areas: results from the Beijing Longitudinal Study of Aging

Differences in frailty between rural and urban older adults have been demonstrated in developed countries. It is not understood how the apparently greater differences in living conditions between different types of regions in China may affect health and outcomes of older Chinese adults. Here, a frailty index (FI) based on the accumulation of health deficits was used to investigate health and survival differences in older Chinese men and women. We studied rural (n = 1121) and urban (n = 2136) older adults (55-97 years old) in the Beijing Longitudinal Study of Aging (BLSA), of whom 48.9% (rural) and 35.4% (urban) died over 8 years of follow-up. The FI was generated from 35 self-reported health deficits. The mean FI increased exponentially with age (r² = 0.87) and was higher in women than in men. The death rate increased significantly with increases in the FI, but women showed a lower death rate than did men. The mean FI in urban older adults (0.12 ± 0.10) was lower than that in their rural counterparts (0.14 ± 0.12, p < 0.001). Urban dwellers showed better survival compared with their counterparts in the rural areas. Adjusted by age, sex, and education level, the hazard ratio for death for each increment of the FI was 1.28 for urban people and 1.27 for rural people. Chinese urban dwellers showed better health and survival than rural dwelling older adults. The FI readily summarized health and mortality differences among different geographic regions, reflecting the impact of the environment, socioeconomics, and medical services on deficit accumulation and on survival.     

Frailty,financial resources and subjective well-being in later life

Though frailty status has recently been linked to poorer quality of life, the impact of income on this relationship has not previously been investigated. Data from a population-based panel study, the English Longitudinal Study of Aging, on 3225 participants aged 65–79 years were analyzed cross-sectionally. A Frailty Index (FI) was determined for each participant as a proportion of accumulated deficits and participants were categorized into four groups on the basis of their FI score: very fit (0.00–0.10), well (0.11–0.14), vulnerable (0.15–0.24), and frail (≥0.25). Subjective well-being was assessed using the CASP-19 instrument, and levels of financial resources quantified using a range of questions about assets and income from a range of sources. Linear regression models were used to assess the relationship between frailty and well-being. There was a significant negative correlation between frailty and well-being; the correlation coefficient between FI and CASP-19 scores was −0.58. The relationship was robust to adjustment for sex, age, and relevant health behaviors (smoking and physical activity) and persisted when participants with depressive symptoms were excluded from analysis. Those with greater financial resources reported better subjective well-being with evidence of a “dose–response” effect. The poorest participants in each frailty category had similar well-being to the most well-off with worse frailty status. Hence, while the association between frailty and poorer subjective well-being is not significantly impacted by higher levels of wealth and income, financial resources may provide a partial buffer against the detrimental psychological effects of frailty.     

A comparison of two approaches to measuring frailty in elderly people

BACKGROUND: Many definitions of frailty exist, but few have been directly compared. We compared the relationship between a definition of frailty based on a specific phenotype with one based on an index of deficit accumulation. METHODS: The data come from all 2305 people 70 years old and older who composed the clinical examination cohort of the second wave of the Canadian Study of Health and Aging. We tested convergent validity by correlating the measures with each other and with other health status measures, and analyzed cumulative index distributions in relation to phenotype. To test criterion validity, we evaluated survival (institutionalization and all-cause mortality) by frailty index (FI) score, stratified by the phenotypic definitions as "robust," "pre-frail," and "frail." RESULTS: The measures correlated moderately well with each other (R=0.65) and with measures of function (phenotypic definition R=0.66; FI R=0.73) but less well with cognition (phenotypic definition R=-0.35; FI R=-0.58). The median FI scores increased from 0.12 for the robust to 0.30 for the pre-frail and 0.44 for the frail. Survival was also lower with increasing frailty, and institutionalization was more common, but within each phenotypic class, there were marked differences in outcomes based on the FI values-e.g., among robust people, the median 5-year survival for those with lower FI values was 85%, compared with 55% for those with higher FI values. CONCLUSION: The phenotypic definition of frailty, which offers ready clinical operationalization, discriminates broad levels of risk. The FI requires additional clinical translation, but allows the risk of adverse outcomes to be defined more precisely.     

Frailty and survival of rural and urban seniors: results from the Canadian Study of Health and Aging

BACKGROUND AND AIMS: Relatively little is known about how region of residence influences frailty of seniors. Frailty indexes can be used to investigate these effects. We constructed and validated a frailty index, to investigate the differences in health status between rural and urban seniors. METHODS: We studied rural (n=949) and urban (n=7598) older adults in the Canadian Study of Health and Aging, of whom 22% died over 72 months. The frailty index was generated from 40 self-reported health deficits (symptoms, diseases, disabilities, unfavourable living conditions). RESULTS: The average value of the frailty index increased exponentially with age in both groups (rural: r=0.94; urban: r=0.97, p<0.01) and was highly correlated with mortality (r=0.96 for rural, r=0.97 for urban, p<0.01). Up to age 80, there were few rural-urban differences in frailty. After age 80, the rural sample showed higher mortality than the urban sample. The hazard ratio for death for each increment in the frailty index was 1.38 (1.14-1.72) in rural participants vs 1.18 (1.11-1.26) in urban participants. Women lived longer than men at any index value. CONCLUSIONS: Frailty index analysis readily summarizes health and mortality differences between very old rural and urban dwellers, which reflect differences in deficit accumulation, and in the impact of gender on survival. The frailty index provides efficient dimensionality reduction for studying group differences in the health of older adults.