Changes in the severity and lethality of age-related health deficit accumulation in the USA between 1999 and 2018: a population-based cohort study

BACKGROUND: With an ageing population, the number of people with frailty is increasing. Despite this trend, the extent to which the severity and lethality of frailty have changed over time is not well understood. We aimed to investigate how frailty severity and lethality have changed over an 18-year period in the USA. METHODS: In this population-based observational study, we used data from the National Health and Nutrition Examination Survey (NHANES) to identify community-dwelling individuals (aged ≥20 years) in the USA between 1999 and 2018. We analysed data from a series of ten 2-year, nationally representative, cross-sectional, prospective studies (from 1999–2000 to 2017–18) from the NHANES. Frailty was measured by use of the deficit accumulation approach (ie, a 46-item frailty index). The proportion of individuals categorised as non-frail, or living with very mild frailty, mild frailty, moderate frailty, and severe frailty were compared across cohorts. Random-effects models were used to examine the association between frailty index score and sex, age, and cohort. Mortality status as of Dec 31, 2015, was ascertained by use of National Death Index data, and 5-year mortality was available in the first six cohorts (1999–2010). Cox regression models and Kaplan-Meier curves were used to estimate the association between frailty index scores and mortality. FINDINGS: In total, 49 004 individuals were included in our study. Associations were mainly non-linear (quadratic), with frailty increasing at a faster rate in more recent cohorts. Between 1999 and 2018, the proportion of non-frail individuals decreased by 10·4% (from 2747 [63·8%; 95% CI 61·9–65·6] of 4307 to 2884 [53·4%; 51·3–55·5] of 5399), whereas the proportion of individuals with very mild frailty increased by 2·4% (from 987 [22·9%; 21·3–24·6] to 1365 [25·3%; 23·5–27·2]), by 2·7% (from 370 [8·6%; 7·7–9·6] to 609 [11·3%; 10·1–12·5]) in those with mild frailty, by 3·1% (from 140 [3·3%; 2·7–3·9] to 347 [6·4%; 5·6–7·4]) in those with moderate frailty, and by 2·1% (from 63 [1·5%; 1·1–1·9] to 195 [3·6%; 3·0–4·3]) in those with severe frailty. Being a woman, older, and from a more recent cohort were associated with higher frailty index scores (all p<0·0001). In more recent cohorts, mean frailty index scores increased more quickly with age (p<0·0001), and sex differences in mean frailty index scores decreased (p<0·0001). In men of all ages and in women aged 35 years or older, mean frailty index scores were higher in more recent cohorts, with larger increases in frailty in older age groups. In 28 692 individuals from the first six cohorts (1999–2000 to 2009–10) with linked mortality data, frailty index scores were significantly associated with mortality (hazard ratio 1·053 [95% CI 1·050–1·057] per 0·01 increase in frailty index score). The absence of an interaction between cohort and frailty index score (p=0·58) suggested that the association between frailty and mortality was similar for all cohorts. INTERPRETATION: Increasing frailty levels in more recent cohorts of middle-aged and older adults combined with stable frailty lethality between 1999 and 2018, suggest a challenge to healthy longevity, with the proportion of individuals with a high degree of frailty continuing to increase. FUNDING: Supported in part by the Canadian Institutes of Health Research

Psychometric properties of a questionnaire to assess exercise-related musculoskeletal injuries in older adults attending a community-based fitness facility

Objectives: There currently exists no reliable or validated tool for the assessment of exercise-related injuries in older adults. The purpose was to develop and evaluate the psychometric properties of a questionnaire to measure exercise-related injury in older adults participating in supervised exercise programmes. Design: The study utilised a repeated survey design. Setting: The study took place at one communitybased older-adult exercise facility. Participants: The questionnaire was administered to 110 community-dwelling older adults (45 men, mean age 75±8 years; 65 women, mean age 71±8 years). All participants completed the survey at both time points. Outcome measures: Test–retest reliability of the selfadministered written questionnaire was determined at two-time points. The questionnaire asked participants about their exercise-related injury incurred at the facility in the 12 months. Items included the mechanism, cause and site of injury. The minimum requirement for reliability (κ coefficient) was set at 0.80. Results: 16% (n=18) reported having an injury. Test–retest reliability ranged from 0.76 to 1.00, with all but type of injury (0.76) having κ coefficients greater than 0.80. The lower extremities were the most common site of exercise-related injury. Overexertion movements were the most common cause of injury occurring during strength training exercises. Conclusions: The present questionnaire assessing the 12-month recall in older adults is a reliable measure of exercise-related injuries and information gained indicates that older adults can safely participate in exercise activities.Liza Stathokostas, Olga Theou, Tony Vandervoort, Parminder Rain

Associations between a laboratory frailty index and adverse health outcomes across age and sex

Objective: Early frailty may be captured by a frailty index (FI) based entirely on vital signs and laboratory tests. Our aim was to examine associations between a laboratory-based FI (FI-Lab) and adverse health outcomes, and investigate how this changed with age. Methods: Up to 8988 individuals aged 20+ years from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey cohorts were included. Characteristics of the FI-Lab were compared to those of a self-reported clinical FI. Associations between each FI and health care use, self-reported health, and disability were examined in the full sample and across age groups. Results: Laboratory-based FI scores increased with age but did not demonstrate expected sex differences. Women aged 20-39 years had higher FI scores than men; this pattern reversed after age 60 years. FI-Lab scores were associated with poor self-reported health (odds ratio[95% confidence interval]: 1.46[1.39-1.54]), high health care use (1.35[1.29-1.42]), and high disability (1.41[1.32-1.50]), even among those aged 20-39 years. Conclusion: Higher FI-Lab scores were associated with poor health outcomes at all ages. Associations in the youngest group support the notion that deficit accumulation occurs across the lifespan. FI-Lab scores could be utilized as an early screening tool to identify deficit accumulation at the cellular and molecular level before they become clinically visible

The role of illness acuity on the association between frailty and mortality in emergency department patients referred to internal medicine.

Background: we investigated whether two frailty tools predicted mortality among emergency department (ED) patients referred to internal medicine and how the level of illness acuity influenced any association between frailty and mortality.Methods: two tools, embedded in a Comprehensive Geriatric Assessment (CGA), were the clinical frailty scale (CFS) and a 57-item deficit accumulation frailty index (FI-CGA). Illness acuity was assessed using the Canadian Triage and Acuity Scale (CTAS). We examined all-cause 30-day and 6-month mortality and time to death.Results: in 808 ED patients (mean age ± SD 80.8 ± 8.8, 54.4% female), the mean FI-CGA score was 0.44 ± 0.14, and the CFS was 5.6 ± 1.6. A minority (307; 38%) were classified as having high acuity (CTAS: 1-2). The 30-day mortality rate was 17%; this increased to 34% at 6 months. Compared to well patients with low acuity, the risk of 30-day mortality was 22.5 times (95% CI: 9.35-62.12) higher for severely frail patients with high acuity; 53% of people with very severe frailty (CFS = 8) and high acuity died within 30 days. When acuity was low, the risk for 30-day mortality was significantly higher only among those with very high levels of frailty (CFS 7-9, FI-CGA > 0.5). When acuity was high, even lower levels of frailty (CFS 5-6, FI-CGA 0.4-0.5) were associated with higher 30-day mortality.Conclusions: across levels of frailty, higher acuity increased mortality risk. When acuity was low, the risk was significant only when the degree of frailty was high, whereas when acuity was high, even lower levels of frailty were associated with greater mortality risk

Accumulation of non-traditional risk factors for coronary heart disease is associated with incident coronary heart disease hospitalization and death

Assessing multiple traditional risk factors improves prediction for late-life diseases, including coronary heart disease (CHD). It appears that non-traditional risk factors can also predict risk. The objective was to investigate contributions of non-traditional risk factors to coronary heart disease risk using a deficit accumulation approach.Community-dwelling adults with no known history of CHD (n = 2195, mean age 46.9±18.7 years, 51.8% women) participated in the 1995 Nova Scotia Health Survey. Three risk factor indices were constructed to quantify the proportion of deficits present in individuals: 1) a 17-item Non-Traditional Risk Factor Index (e.g. sinusitis, arthritis); 2) a 9-item Traditional Risk Factor Index (e.g. hypertension, diabetes); and 3) a frailty index (25 items combined from the other two index measures). Ten-year risks of CHD events (defined as CHD-related hospitalization and CHD-related mortality) were evaluated.The Non-Traditional Risk Factor Index, made up of health deficits unrelated to CHD, was independently associated with incident CHD events over 10 years after controlling for age, sex, and the Traditional Risk Factor Index [adjusted {adj.} Hazard Ratio {HR} = 1.31; Confidence Interval {CI} 1.14-1.51]. When all health deficits, both those related and unrelated to CHD, were included in a frailty index the corresponding adjusted hazard ratio was 1.61; CI 1.40-1.85.Both traditional and non-traditional risk factor indices are independently associated with incident CHD events. CHD risk assessment may benefit from consideration of general health information as well as from traditional risk factors.Lindsay M. K. Wallace, Olga Theou, Susan A. Kirkland, Michael R. H. Rockwood, Karina W. Davidson, Daichi Shimbo, Kenneth Rockwoo

A frailty index from common clinical and laboratory tests predicts increased risk of death across the life course

A frailty index (FI) based entirely on common clinical and laboratory tests might offer scientific advantages in understanding ageing and pragmatic advantages in screening. Our main objective was to compare an FI based on common laboratory tests with an FI based on self-reported data; we additionally investigated if the combination of subclinical deficits with clinical ones increased the ability of the FI to predict mortality. In this secondary analysis of the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey data, 8888 individuals aged 20+ were evaluated. Three FIs were constructed: a 36-item FI using self-reported questionnaire data (FI-Self-report); a 32-item FI using data from laboratory test values plus pulse and blood pressure measures (FI-Lab); and a 68-item FI that combined all items from each index (FI-Combined). The mean FI-Lab score was 0.15 ± 0.09, the FI-Self-report was 0.11 ± 0.11 and FI-Combined was 0.13 ± 0.08. Each index showed some typical FI characteristics (skewed distribution with long right tail, non-linear increase with age). Even so, there were fewer people with low frailty levels and a slower increase with age for the FI-Lab compared to the FI-Self-report. Higher frailty level was associated with higher risk of death, although it was strongest at older ages. Both FI-Lab and FI-Self-report remained significant in a combined model predicting death. The FI-Lab was feasible and valid, demonstrating that even subclinical deficit accumulation increased mortality risk. This suggests that deficit accumulation, from the subcellular to the clinically visible is a useful construct that may advance our understanding of the ageing process.Joanna M. Blodgett, Olga Theou, Susan E. Howlett, Kenneth Rockwoo

Comparison of alternate scoring of variables on the performance of the frailty index

Background: The frailty index (FI) is used to measure the health status of ageing individuals. An FI is constructed as the proportion of deficits present in an individual out of the total number of age-related health variables considered. The purpose of this study was to systematically assess whether dichotomizing deficits included in an FI affects the information value of the whole index. Methods: Secondary analysis of three population-based longitudinal studies of community dwelling individuals: Nova Scotia Health Survey (NSHS, n = 3227 aged 18+), Survey of Health, Ageing and Retirement in Europe (SHARE, n = 37546 aged 50+), and Yale Precipitating Events Project (Yale-PEP, n = 754 aged 70+). For each dataset, we constructed two FIs from baseline data using the deficit accumulation approach. In each dataset, both FIs included the same variables (23 in NSHS, 70 in SHARE, 33 in Yale-PEP). One FI was constructed with only dichotomous values (marking presence or absence of a deficit); in the other FI, as many variables as possible were coded as ordinal (graded severity of a deficit). Participants in each study were followed for different durations (NSHS: 10 years, SHARE: 5 years, Yale PEP: 12 years). Results: Within each dataset, the difference in mean scores between the ordinal and dichotomous-only FIs ranged from 0 to 1.5 deficits. Their ability to predict mortality was identical; their absolute difference in area under the ROC curve ranged from 0.00 to 0.02, and their absolute difference between Cox Hazard Ratios ranged from 0.001 to 0.009. Conclusions: Analyses from three diverse datasets suggest that variables included in an FI can be coded either as dichotomous or ordinal, with negligible impact on the performance of the index in predicting mortality.Fernando G Peña, Olga Theou, Lindsay Wallace, Thomas D Brothers, Thomas M Gill, Evelyne A Gahbauer, Susan Kirkland, Arnold Mitnitski and Kenneth Rockwoo

Recurrent measurement of frailty is important for mortality prediction: findings from the North West Adelaide Health Study

OBJECTIVES:Frailty places individuals at greater risk of adverse health outcomes. However, it is a dynamic condition and may not always lead to decline. Our objective was to determine the relationship between frailty status (at baseline and follow-up) and mortality using both the frailty phenotype (FP) and frailty index (FI). DESIGN:Population-based cohort. SETTING:Community-dwelling older adults. PARTICIPANTS:A total of 909 individuals aged 65 years or older (55% female), mean age 74.4 (SD 6.2) years, had frailty measurement at baseline. Overall, 549 participants had frailty measurement at two time points. MEASUREMENTS:Frailty was measured using the FP and FI, with a mean 4.5 years between baseline and follow-up. Mortality was matched to official death records with a minimum of 10 years of follow-up. RESULTS:For both measures, baseline frailty was a significant predictor of mortality up to 10 years, with initially good predictive ability (area under the curve [AUC] = .8-.9) decreasing over time. Repeated measurement at follow-up resulted in good prediction compared with lower (AUC = .6-.7) discrimination of equivalent baseline frailty status. In a multivariable model, frailty measurement at follow-up was a stronger predictor of mortality compared with baseline. Frailty change for the Continuous FI was a significant predictor of decreased or increased mortality risk based on corresponding improvement or worsening of score (hazard ratio = 1.04; 95% confidence interval = 1.02-1.07; P = .001). CONCLUSIONS:Frailty measurement is a good predictor of mortality up to 10 years; however, recency of frailty measurement is important for improved prediction. A regular review of frailty status is required in older adults.Mark Q. Thompson, Olga Theou, Graeme R. Tucker, Robert J. Adams, and Renuka Visvanatha

Geospatial modelling of the prevalence and changing distribution of frailty in Australia – 2011 to 2027

Background and objectives: Detailed information about the current and future geographic distribution of Australia's frail population provides critical evidence to inform policy, resource allocation and planning initiatives that aim to treat and reverse frailty. Frailty is associated with poor health outcomes, including disability and death. It is also characterised by increased health care usage and costs. Understanding the distribution and growth of frailty is important for planning and budgeting service provision and health interventions aimed to support the needs of Australia's growing ageing population. The objective of this research is to provide baseline mapping and area level population estimates of Australia's current and future frail and pre-frail populations. Research design and methods: Geospatial modelling was applied to national frailty prevalence rates to provide estimates of the size, distribution and potential growth of Australia's frail and pre-frail population. Results: It is estimated that in 2016 approximately 415,769 people living in Australia aged 65 years or more are frail and almost 1.7 million people are pre-frail. In future years, as the population ages, these figures will increase rapidly, reaching 609,306 frail and 2,248,977 pre-frail by 2027, if prevalence continues at current levels. The geographic distribution of this projected growth is not uniform and while the largest frail populations will continue to be located in the major cities, the fastest growth will be in the outer metropolitan, regional and remote areas. Discussion and implications: The projected growth of frail populations in outer metropolitan, regional and remote areas may be reduced by targeting health interventions in these areas and improving access to support services. Frailty is a dynamic condition that is amenable to intervention. Reducing frailty will lead to benefits in wellbeing for older Australians in addition to reductions in health care costs.D. Taylor, H. Barrie, J. Lange, M.Q.Thompson, O.Theou, R.Visvanatha

Predictors of transitions in frailty severity and mortality among people aging with HIV.

BACKGROUND: People aging with HIV show variable health trajectories. Our objective was to identify longitudinal predictors of frailty severity and mortality among a group aging with HIV. METHODS: Exploratory analyses employing a multistate transition model, with data from the prospective Modena HIV Metabolic Clinic Cohort Study, based in Northern Italy, begun in 2004. Participants were followed over four years from their first available visit. We included all 963 participants (mean age 46.8±7.1; 29% female; 89% undetectable HIV viral load; median current CD4 count 549, IQR 405–720; nadir CD4 count 180, 81–280) with four-year data. Frailty was quantified using a 31-item frailty index. Outcomes were frailty index score or mortality at four-year follow-up. Candidate predictor variables were baseline frailty index score, demographic (age, sex), HIV-disease related (undetectable HIV viral load, current CD4+ T-cell count, nadir CD4 count, duration of HIV infection, and duration of antiretroviral therapy [ARV] exposure), and behavioral factors (smoking, injection drug use (IDU), and hepatitis C virus co-infection). RESULTS: Four-year mortality was 3.0% (n = 29). In multivariable analyses, independent predictors of frailty index at follow-up were baseline frailty index (RR 1.06, 95% CI 1.05–1.07), female sex (RR 0.93, 95% CI 0.87–0.98), nadir CD4 cell count (RR 0.96, 95% CI 0.93–0.99), duration of HIV infection (RR 1.06, 95% CI 1.01–1.12), duration of ARV exposure (RR 1.08, 95% CI 1.02–1.14), and smoking pack-years (1.03, 1.01–1.05). Independent predictors of mortality were baseline frailty index (OR 1.19, 1.02–1.38), current CD4 count (0.34, 0.20–0.60), and IDU (2.89, 1.30–6.42). CONCLUSIONS: Demographic, HIV-disease related, and social and behavioral factors appear to confer risk for changes in frailty severity and mortality among people aging with HIV