Association Between Mobility Measured During Hospitalization and Functional Outcomes in Older Adults With Acute Myocardial Infarction in the SILVER-AMI Study

Importance

Many older survivors of acute myocardial infarction (AMI) experience functional decline, an outcome of primary importance to older adults. Mobility impairment has been proposed as a risk factor for functional decline but has not been evaluated to date in older patients hospitalized for AMI.

Objective

To examine the association of mobility impairment, measured during hospitalization, as a risk marker for functional decline among older patients with AMI.

Design, Setting, and Participants

Prospective cohort study among 94 academic and community hospitals in the United States. Participants were 2587 hospitalized patients with AMI who were 75 years or older. The study dates were January 2013 to June 2017.

Main Outcomes and Measures

Mobility was evaluated during AMI hospitalization using the Timed "Up and Go," with scores categorized as preserved mobility (≤15 seconds to complete), mild impairment (>15 to ≤25 seconds to complete), moderate impairment (>25 seconds to complete), and severe impairment (unable to complete). Self-reported function in activities of daily living (ADLs) (bathing, dressing, transferring, and walking around the home) and walking 0.4 km (one-quarter mile) was assessed at baseline and 6 months after discharge. The primary outcomes were worsening of 1 or more ADLs and loss of ability to walk 0.4 km from baseline to 6 months after discharge. The association between mobility impairment and risk of functional decline was evaluated with multivariable-adjusted logistic regression.

Results

Among 2587 hospitalized patients with AMI, the mean (SD) age was 81.4 (4.8) years, and 1462 (56.5%) were male. More than half of the cohort exhibited mobility impairment during AMI hospitalization (21.8% [564 of 2587] had mild impairment, 16.0% [414 of 2587] had moderate impairment, and 15.2% [391 of 2587] had severe impairment); 12.8% (332 of 2587) reported ADL decline, and 16.7% (431 of 2587) reported decline in 0.4-km mobility. Only 3.8% (30 of 800) of participants with preserved mobility experienced any ADL decline compared with 6.9% (39 of 564) of participants with mild impairment (adjusted odds ratio [aOR], 1.24; 95% CI, 0.74-2.09), 18.6% (77 of 414) of participants with moderate impairment (aOR, 2.67; 95% CI, 1.67-4.27), and 34.7% (136 of 391) of participants with severe impairment (aOR, 5.45; 95% CI, 3.29-9.01). Eleven percent (90 of 800) of participants with preserved mobility declined in ability to walk 0.4 km compared with 15.2% (85 of 558) of participants with mild impairment (aOR, 1.51; 95% CI, 1.04-2.20), 19.0% (78 of 411) of participants with moderate impairment (aOR, 2.03; 95% CI, 1.37-3.02), and 24.6% (95 of 386) of participants with severe impairment (aOR, 3.25; 95% CI, 2.02-5.23).

Conclusions and Relevance

This study's findings suggest that mobility impairment assessed during hospitalization may be a potent risk marker for functional decline in older survivors of AMI. These findings also suggest that brief, validated assessments of mobility should be part of the care of older hospitalized patients with AMI to identify those at risk for this important patient-centered outcome.

SPOUSAL ASSOCIATIONS IN MONTHLY REPORTS OF DISABILITY IN THE PRECIPITATING EVENTS PROJECT

While many prior studies have evaluated the antecedents and consequences of changes in disability, few have considered the social context. As nearly 60% of older adults currently live with a spouse or intimate partner, it is important to examine spousal influences on disability. This study examined spousal associations in self-reported disability using data from the Precipitating Events Project, an ongoing longitudinal study of 754 initially nondisabled community living adults age 70 and over who have had monthly assessments of functional status since 1999. We hypothesized that one spouse’s level of disability would be associated with increases in the other spouse’s subsequent disability. We used the Actor Partner Interdependence Model (APIM), a statistical modeling framework that accounts for the interdependence in two-person data and tests the associations of both self (actor) and partner influences on outcomes. We used multilevel, longitudinal APIMs to examine lagged associations in spouses’ monthly reports of disability in 13 activities of daily living (e.g., walking a quarter mile, bathing) in the 37 married couples. As hypothesized, one partner’s prior disability level was significantly associated with the other partner’s (the actor’s) subsequent disability level (B = .674, SE = .012, p < .001) after controlling for the actor’s prior disability level. Also, when both couple members had higher levels of prior disability, they were particularly at risk of subsequent increases in disability (B = .016, SE = .003, p < .001). Incorporating partner disability level in modeling individuals’ outcomes provides greater precision in predicting future disability levels.

Sex-Based Differences in Presentation, Treatment, and Complications Among Older Adults Hospitalized for Acute Myocardial Infarction: The SILVER-AMI Study

BACKGROUND

Studies of sex-based differences in older adults with acute myocardial infarction (AMI) have yielded mixed results. We, therefore, sought to evaluate sex-based differences in presentation characteristics, treatments, functional impairments, and in-hospital complications in a large, well-characterized population of older adults (≥75 years) hospitalized with AMI.

METHODS AND RESULTS

We analyzed data from participants enrolled in SILVER-AMI (Comprehensive Evaluation of Risk Factors in Older Patients With Acute Myocardial Infarction)-a prospective observational study consisting of 3041 older patients (44% women) hospitalized for AMI. Participants were stratified by AMI subtype (ST-segment-elevation myocardial infarction [STEMI] and non-STEMI [NSTEMI]) and subsequently evaluated for sex-based differences in clinical presentation, functional impairments, management, and in-hospital complications. Among the study sample, women were slightly older than men (NSTEMI: 82.1 versus 81.3, P<0.001; STEMI: 82.2 versus 80.6, P<0.001) and had lower rates of prior coronary disease. Women in the NSTEMI subgroup presented less frequently with chest pain as their primary symptom. Age-associated functional impairments at baseline were more common in women in both AMI subgroups (cognitive impairment, NSTEMI: 20.6% versus 14.3%, P<0.001; STEMI: 20.6% versus 12.4%, P=0.001; activities of daily living disability, NSTEMI: 19.7% versus 11.4%, P<0.001; STEMI: 14.8% versus 6.4%, P<0.001; impaired functional mobility, NSTEMI: 44.5% versus 30.7%, P<0.001; STEMI: 39.4% versus 22.0%, P<0.001). Women with AMI had lower rates of obstructive coronary disease (NSTEMI: P<0.001; STEMI: P=0.02), driven by lower rates of 3-vessel or left main disease than men (STEMI: 38.8% versus 58.7%; STEMI: 24.3% versus 32.1%), and underwent revascularization less commonly (NSTEMI: 55.6% versus 63.6%, P<0.001; STEMI: 87.3% versus 93.3%, P=0.01). Rates of bleeding were higher among women with STEMI (26.2% versus 15.6%, P<0.001) but not NSTEMI (17.8% versus 15.7%, P=0.21). Women had a higher frequency of bleeding following percutaneous coronary intervention with both NSTEMI (11.0% versus 7.8%, P=0.04) and STEMI (22.6% versus 14.8%, P=0.02).

CONCLUSIONS

Among older adults hospitalized with AMI, women had a higher prevalence of age-related functional impairments and, among the STEMI subgroup, a higher incidence of overall bleeding events, which was driven by higher rates of nonmajor bleeding events and bleeding following percutaneous coronary intervention. These differences may have important implications for in-hospital and posthospitalization needs.

Personalized and typical concurrent risk of limitations in social activity and mobility in older persons with multiple chronic conditions and polypharmacy

PURPOSE

We define personalized concurrent risk (PCR) as the subject-specific probability of an index outcome within a defined interval of time, while currently at risk for a separate outcome, where the outcomes are not mutually exclusive and can be jointly modeled with a shared random intercept. We further define typical concurrent risk as the risk obtained by setting the random intercept to null.

METHODS

Drawing data from the Medical Expenditure Panel Survey (cohorts 2008-2013), we jointly model limitations in social activity and mobility over two years among older community-dwelling persons with both hypertension and chronic obstructive pulmonary disease. The joint model uses inverse probability of treatment weighting based on each participant's baseline propensity of polypharmacy (≥5 classes of medication).

RESULTS

Even among participants with the same covariates, older persons with multiple chronic conditions exhibit wide-ranging heterogeneity of the treatment effect from polypharmacy, a risk factor for negative health outcomes among older persons. The magnitude of the PCRs is dominated by the value of the subject-specific random effect.

CONCLUSIONS

Estimates of PCR and typical concurrent risk can be calculated from national or institutional data sets and may facilitate the practice of personalized care for older patients with multiple chronic conditions.

Treatment of Hypertension in Complex Older Adults: How Many Medications Are Needed?

Background: Many older adults with hypertension receive multiple antihypertensives. It is unclear whether treatment with several antihypertensive classes results in greater cardiovascular benefits than fewer antihypertensive classes. Objectives: We investigated (a) the longitudinal associations between treatment with ≥ 3 versus 1-2 classes and death and major adverse cardiovascular events (MACE) and (b) whether these associations varied by the presence of mobility disability. Methods: We included 6,011 treated hypertensive adults ≥65 from the Medical Expenditure Panel Survey (MEPS), a nationally representative community sample. Times to MACE and death were compared between those receiving ≥3 versus 1-2 classes using multivariable proportional hazards regression. We used inverse probability of treatment weighting to account for indication and contraindication bias. Results: There were no significant differences in the risk of mortality (hazard ratio [HR] = 0.96, p = .769) or MACE (HR = 1.10, p = .574) between the exposure groups, and there were no significant exposure × mobility disability interactions. Discussion: We found no benefit of ≥3 versus 1-2 antihypertensive classes in reducing mortality and cardiovascular events in a representative cohort of older adults, raising concern about the added benefit of additional antihypertensives in the real world.

Joint modeling of concurrent binary outcomes in a longitudinal observational study using inverse probability of treatment weighting for treatment effect estimation

PURPOSE

Correlated healthcare utilization outcomes may be encoded as binary outcomes in epidemiologic studies. We demonstrate how to account for correlation between concurrent binary outcomes and confounding by person characteristics when estimating a treatment effect in observational studies.

METHODS

We present a joint shared-parameter model, weighted by inverse probability of treatment weights (IPTW) to account for confounding. The model is evaluated in a simulation study that emulates the Medical Expenditure Panel Survey data and compared with a covariate-adjusted joint model and with separate outcome models (IPTW weighted and covariate adjusted).

RESULTS

For the IPTW-weighted joint model, relative bias in the estimated treatment effect on outcome 1 ranged from -0.057 to -0.033 and outcome 2 from -0.077 to -0.043. For the covariate-adjusted joint model, relative bias ranged from -0.010 to -0.083 for outcome 1 and from -0.087 to -0.110 for outcome 2. The covariate-adjusted joint model estimated the effect more closely than the covariate-adjusted separate model. The IPTW-weighted joint model estimated the effect more closely for outcome 1.

CONCLUSIONS

The IPTW-weighted joint model handles correlation between binary outcomes, adjusts for confounding, and estimates the treatment effect accurately in observational studies. We illustrate the contribution of person-specific effects in estimating personalized risk.

Bayesian Model Averaging for Selection of a Risk Prediction Model for Death within Thirty Days of Discharge: The SILVER-AMI Study

We describe a selection process for a multivariable risk prediction model of death within 30 days of hospital discharge in the SILVER-AMI study. This large, multi-site observational study included observational data from 2000 persons 75 years and older hospitalized for acute myocardial infarction (AMI) from 94 community and academic hospitals across the United States and featured a large number of candidate variables from demographic, cardiac, and geriatric domains, whose missing values were multiply imputed prior to model selection. Our objective was to demonstrate that Bayesian Model Averaging (BMA) represents a viable model selection approach in this context. BMA was compared to three other backward-selection approaches: Akaike information criterion, Bayesian information criterion, and traditional p-value. Traditional backward-selection was used to choose 20 candidate variables from the initial, larger pool of five imputations. Models were subsequently chosen from those candidates using the four approaches on each of 10 imputations. With average posterior effect probability ≥ 50% as the selection criterion, BMA chose the most parsimonious model with four variables, with average C statistic of 78%, good calibration, optimism of 1.3%, and heuristic shrinkage of 0.93. These findings illustrate the utility and flexibility of using BMA for selecting a multivariable risk prediction model from many candidates over multiply imputed datasets.

Taking to Bed at the End of Life

OBJECTIVES

To evaluate the time course of "taking to bed" at the end of life and determine whether it differs according to age, sex, and condition leading to death.

DESIGN

Prospective longitudinal study.

SETTING

Greater New Haven, Connecticut.

PARTICIPANTS

A total of 651 decedents from a cohort of 754 community-living persons, 70+ years of age.

MEASUREMENTS

During the last 2 years of life, the occurrence of bed rest and number of days in bed, two indicators of bed rest burden, were ascertained each month. Bed rest was defined as staying in bed for at least a half day due to an illness, injury, or other problem.

RESULTS

The occurrence of bed rest increased modestly from 12.4% at 24 months before death to 19.0% at 5 months before death, before increasing exponentially to 51.6% at 1 month before death. The median number of days in bed fluctuated within a narrow range of 3 to 7 from 24 months to 4 months before death, before increasing substantially to a high of 14 at 1 month before death. In the last 2 years of life, the burden of bed rest did not differ by age but was significantly greater in women than men. Among the conditions leading to death, the burden of bed rest was highest among persons dying from organ failure and cancer, lowest for sudden death, and intermediate for frailty, advanced dementia, and other conditions.

CONCLUSION

The burden of bed rest at the end of life is greater in women than men, does not differ by age, and is highest among persons dying from organ failure and cancer. The steep increases observed in the last 3 to 5 months of life suggest that taking to bed may be an indicator that death is approaching and should prompt discussions about referral to hospice among older persons with serious illness.

Days Spent at Home in the Last Six Months of Life Among Community-Living Older Persons

BACKGROUND

Days spent at home has recently been identified as an important patient-centered outcome; yet, relatively little is known about time spent at home at the end of life among community-living older persons.

METHODS

The analytic sample included 457 decedents from an ongoing cohort study of 754 community-living persons, aged ≥70 years. Days spent at home were calculated as 180 days minus the number of days in a hospital, nursing home, or hospice facility. The condition leading to death was determined from death certificates and comprehensive assessments.

RESULTS

The median number of days at home was 159 (interquartile range 125-174). There were 138 (30.2%) decedents at home during the entire 6-month period, while 163 (35.7%) were at home for fewer than 150 days. Days at home did not differ significantly by age (P = .922), sex (P = .238), or race/ethnicity (P = .199), but did differ according to the condition leading to death (P = .001), with the lowest value observed for organ failure (150 [106.5-168.5]), highest values for sudden death (177 [172-179]) and cancer (167 [140-174]), and intermediate values for advanced dementia (164 [118-174]), frailty (160.5 [130-174]), and other conditions (153 [118-175]).

CONCLUSIONS

Among community-living older persons, days spent at home in the last 6 months of life do not differ by age, sex, or race/ethnicity, but are significantly lower for persons dying from organ failure. Additional efforts may be warranted to optimize time spent at home at the end of life, especially among older persons dying from organ failure.

The Competing Risk of Death in Longitudinal Geriatric Outcomes

OBJECTIVES

To address the competing risk of death in longitudinal studies of older persons, we demonstrate sensitivity analyses that evaluate robustness of associations between exposures and three outcome types: dichotomous, count, and time to event.

DESIGN

A secondary analysis of data from a prospective cohort study.

SETTING

Community-based data from the Precipitating Events Project in New Haven, CT.

PARTICIPANTS

Persons 70 years and older who were initially community dwelling and without disability in the four basic activities of daily living (N = 754).

MEASUREMENTS

Missing outcome values from decedents were multiply imputed under different scenarios. Three outcomes were examined: dichotomous fall-related hospitalization (FRH); a count (0-13) of total disability in each of the 6 months after discharge; and days to functional recovery among those whose disability worsened in the hospital. Each outcome had a different exposure: for dichotomous, indicators of being overweight or obese; for count, frailty from the Fried phenotype (0-5, where not frail = 0, prefrail = 1-2, and frail = 3-5); for days to recovery, vision impairment.

RESULTS

For FRH, being overweight or obese lost significance when decedents were kept in the risk pool without outcome events for over 10 years. For disability count and time to recovery, with follow-up of 6 months, exposures only lost significance under highly implausible clinical scenarios.

CONCLUSION

This method facilitates evaluation of potential bias from the competing risk of death in longitudinal studies for nondeath outcomes that are not necessarily time to event. Results suggest that death introduces substantive bias when long-term follow-up results in cumulatively high levels of mortality. J Am Geriatr Soc 67:357-362, 2019.

Burden of Restricted Activity and Associated Symptoms and Problems in Late Life and at the End of Life

OBJECTIVES

To compare rates of restricted activity and associated symptoms and problems in the last 6 months of life with those in the period before the last 6 months of life.

DESIGN

Prospective cohort study.

SETTING

Greater New Haven, Connecticut.

PARTICIPANTS

Community-living persons aged 70 and older (N=754).

MEASUREMENTS

The occurrence of restricted activity (staying in bed for at least half the day or cutting down on usual activities) and 24 prespecified symptoms and problems leading to restricted activity was ascertained monthly for nearly 19 years.

RESULTS

Rates of restricted activity per 100 person-months were 36.5 in the last 6 months of life versus 16.1 in the period before the last 6 months of life (P<.001). Of 737 participants with 1 month or more of restricted activity, rates of restricting symptoms per 100 person-months of restricted activity ranged from 8.0 for frequent or painful urination to 65.6 for been fatigued, and rates of restricting problems ranged from 0.1 for problem with alcohol to 23.4 for been afraid of falling. Rates were significantly higher in the last 6 months of life than in the prior period for 13 of the 24 restricting symptoms and problems (P<.05), most notably for shortness of breath (38.6 vs 21.8), weakness (37.3 vs 18.9), and confusion (31.2 vs 9.8). Mean (standard error) number of restricting symptoms and problems was significantly higher in the last 6 months of life (6.1 (0.1)) than in the prior period (4.7 (0.03)) (P<.001).

CONCLUSION

Rates of restricted activity and associated symptoms and problems are substantially greater in the last 6 months of life than in the period before the last 6 months of life. Enhanced palliative care strategies may be needed to diminish the burden of distressing symptoms and problems at the end of life. J Am Geriatr Soc 66:2282-2288, 2018.

Multimorbidity Burden and Adverse Outcomes in a Community-Based Cohort of Adults with Heart Failure

OBJECTIVES

To assess multimorbidity burden and its association with clinical outcomes in adults with heart failure (HF) according to sex, age, and HF type.

DESIGN

Retrospective cohort study.

SETTING

Five healthcare delivery systems across the United States.

PARTICIPANTS

Adults with HF (N=114,553).

MEASUREMENTS

We characterized participants with respect to the presence of 26 chronic conditions categorized into quartiles based on overall burden of comorbidity (<5, 5-6, 7-8, ≥9). Outcomes included all-cause death and hospitalization for HF or any cause. Multivariable Cox regression was used to evaluate the adjusted association between categorized burden of multimorbidity burden and outcomes.

RESULTS

Individuals with more morbidities were more likely to die than those with fewer then 5 morbidities (5-6 morbidities: adjusted hazard ratio (aHR)=1.27 (95% confidence interval (CI)=1.24-1.31; 7-8 morbidities: aHR=1.52, 95% CI=1.48-1.57; ≥9 morbidities: aHR=1.92, 95% CI=1.86-1.99). There was a graded, higher adjusted rate of any-cause hospitalization associated with 5 or 6 (aHR=1.28, 95% CI=1.25-1.30), 7 or 8 (aHR=1.47, 95% CI=1.44-1.50), or 9 or more (aHR=1.77, 95% CI=1.73-1.82) morbidities (vs <5). Similar findings were observed for HF-specific hospitalization in those with 5 or 6 (aHR=1.22, 95% CI=1.19-1.26), 7 or 8 (aHR=1.39, 95% CI=1.34-1.44), or 9 or more (aHR 1.68, 95% CI=1.61-1.74) morbidities (vs <5). Consistent findings were seen according to sex, age group, and HF type (preserved, reduced, borderline HF), in the association between categorical burden of multimorbidity and outcomes especially prominent in individuals younger than 65.

CONCLUSION

After adjustment, higher levels of multimorbidity predicted worse HF outcomes and may be an important consideration in strategies to improve clinical and person-centered outcomes. J Am Geriatr Soc 66:2305-2313, 2018.

Time-varying social support and time to death in the cardiovascular health study

OBJECTIVES

There is a consensus that social connectedness is integral for a long, healthy life. However, studies of social support and survival have primarily relied on baseline social support measures, potentially missing the effects of fluctuations of perceived support over time. This is especially important for older adults who experience increased changes in disability. This study examined whether among older adults time-varying perceived social support was associated with time to death (main effect model of support) and whether time-varying disability was a modifier (stress-buffering model of support). Gender and marital status were also examined as modifiers.

METHODS

Older adults in the Cardiovascular Health Study (N = 5,201) completed self- report measures of demographics and psychological health and clinical risk factors for mortality at baseline (1989-1990). Perceived social support and disability were measured from baseline through Wave 11 (1998-1999). Cox regression of time to death with time-varying covariates was performed.

RESULTS

Time-varying as well as baseline-only perceived social support was associated with greater survival in the unadjusted models but not after adjustment. Gender, marital status, and time-varying disability were not significant modifiers.

CONCLUSIONS

In contrast with the previously reported association between baseline individual differences in perceived social support and time to death, older adults' baseline-only and fluctuating perceptions of perceived support over time were not associated with time to death after adjustment for other clinical physical and psychological risk factors. Research is needed to identify other relationship factors that may be more informative as time-varying predictors of health and longevity in large longitudinal data sets. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Association between death and loss of stage N2 sleep features among critically Ill patients with delirium

PURPOSE

Critically ill patients experience significant sleep disruption. In this study of ICU patients with delirium, we evaluated associations between the loss of stage N2 features (K-complexes, sleep spindles), grade of encephalopathy based on electroencephalography (EEG), and intensive care unit (ICU) outcomes. We hypothesized that loss of stage N2 features is associated with more severe grades of encephalopathy and worse ICU outcomes including death.

MATERIALS AND METHODS

This was an observational cohort study of 93 medical ICU patients without primary acute brain injury who underwent continuous EEG. Type and severity of critical illness, sedative-hypnotic use, length of stay, modified Rankin Scale at hospital discharge, and death during hospitalization were abstracted from the medical record. EEG was evaluated for grade of encephalopathy and sleep features.

RESULTS

Patients without K-complexes or without sleep spindles had more severe encephalopathy and higher odds of death. The odds ratio for patients without K-complexes was 18.8 (p = .046). The odds ratio for patients without sleep spindles was 6.3 (p = .036).

CONCLUSIONS

Loss of stage N2 features is common and associated with more severe encephalopathy and higher odds of death. The absence of either Stage N2 feature, K complexes or sleep spindles, may have important prognostic value.

Association of intensive care unit delirium with sleep disturbance and functional disability after critical illness: an observational cohort study

Background

In medical intensive care unit (MICU) patients, the predictors of post-discharge sleep disturbance and functional disability are poorly understood. ICU delirium is a risk factor with a plausible link to sleep disturbance and disability. This study evaluated the prevalence of self-reported post-ICU sleep disturbance and increased functional disability, and their association with MICU delirium and other ICU factors.

Methods

This was an observational cohort study of MICU patients enrolled in a biorepository and assessed upon MICU admission by demographics, comorbidities, and baseline characteristics. Delirium was assessed daily using the Confusion Assessment Method for the ICU. Telephone follow-up interview instruments occurred after hospital discharge and included the Pittsburgh Sleep Quality Index (PSQI), and basic and instrumental activities of daily living (BADLs, IADLs) for disability. We define sleep disturbance as a PSQI score > 5 and increased disability as an increase in composite BADL/IADL score at follow-up relative to baseline. Multivariable regression modeled the associations of delirium and other MICU factors on follow-up PSQI scores and change in disability scores.

Results

PSQI and BADL/IADL instruments were completed by 112 and 122 participants, respectively, at mean 147 days after hospital discharge. Of those surveyed, 63% had sleep disturbance by PSQI criteria, and 37% had increased disability by BADL/IADL scores compared to their pre-MICU baseline. Total days of MICU delirium (p = 0.013), younger age (p = 0.013), and preexisting depression (p = 0.025) were significantly associated with higher PSQI scores at follow-up. Lower baseline disability (p < 0.001), older age (p = 0.048), and less time to follow-up (p = 0.024) were significantly associated with worsening post-ICU disability, while the occurrence of MICU delirium showed a trend toward association (p = 0.077).

Conclusions

After adjusting for important covariates, total days of MICU delirium were significantly associated with increased post-discharge sleep disturbance. Delirium incidence showed a trend toward association with increased functional disability in the year following discharge.

The Association of Frailty With Post-ICU Disability, Nursing Home Admission, and Mortality: A Longitudinal Study

BACKGROUND

Frailty is a strong indicator of vulnerability among older persons, but its association with ICU outcomes has not been evaluated prospectively (ie, with objective measurements obtained prior to ICU admission). Our objective was to prospectively evaluate the relationship between frailty and post-ICU disability, incident nursing home admission, and death.

METHODS

The parent cohort included 754 adults aged ≥ 70 years, who were evaluated monthly for disability in 13 functional activities and every 18 months for frailty (1998-2014). Frailty was assessed using the Fried index, where frailty, prefrailty, and nonfrailty were defined, respectively, as at least three, one or two, and zero criteria (of five). The analytic sample included 391 ICU admissions.

RESULTS

The mean age was 84.0 years. Frailty and prefrailty were present prior to 213 (54.5%) and 140 (35.8%) of the 391 admissions, respectively. Relative to nonfrailty, frailty was associated with 41% greater disability over the 6 months following a critical illness (adjusted risk ratio, 1.41; 95% CI, 1.12-1.78); prefrailty conferred 28% greater disability (adjusted risk ratio, 1.28; 95% CI, 1.01-1.63). Frailty (odds ratio, 3.52; 95% CI, 1.23-10.08), but not prefrailty (odds ratio, 2.01; 95% CI, 0.77-5.24), was associated with increased nursing home admission. Each one-point increase in frailty count (range, 0-5) was associated with double the likelihood of death (hazard ratio, 2.00; 95% CI, 1.33-3.00) through 6 months of follow-up.

CONCLUSIONS

Pre-ICU frailty status was associated with increased post-ICU disability and new nursing home admission among ICU survivors, and death among all admissions. Pre-ICU frailty status may provide prognostic information about outcomes after a critical illness.

Guideline-Recommended Medications and Physical Function in Older Adults with Multiple Chronic Conditions

BACKGROUND/OBJECTIVES

The benefit or harm of a single medication recommended for one specific condition can be difficult to determine in individuals with multiple chronic conditions and polypharmacy. There is limited information on the associations between guideline-recommended medications and physical function in older adults with multiple chronic conditions. The objective of this study was to estimate the beneficial or harmful associations between guideline-recommended medications and decline in physical function in older adults with multiple chronic conditions.

DESIGN

Prospective observational cohort.

SETTING

National.

PARTICIPANTS

Community-dwelling adults aged 65 and older from the Medicare Current Beneficiary Survey study (N = 3,273). Participants with atrial fibrillation, coronary artery disease, depression, diabetes mellitus, or heart failure were included.

MEASUREMENTS

Self-reported decline in physical function; guideline-recommended medications; polypharmacy (taking <7 vs ≥7 concomitant medications); chronic conditions; and sociodemographic, behavioral, and health risk factors.

RESULTS

The risk of decline in function in the overall sample was highest in participants with heart failure (35.4%, 95% confidence interval (CI) = 26.3-44.5) and lowest for those with atrial fibrillation (20.6%, 95% CI = 14.9-26.2). In the overall sample, none of the six guideline-recommended medications was associated with decline in physical function across the five study conditions, although in the group with low polypharmacy exposure, there was lower risk of decline in those with heart failure taking renin angiotensin system blockers (hazard ratio (HR) = 0.40, 95% CI = 0.16-0.99) and greater risk of decline in physical function for participants with diabetes mellitus taking statins (HR = 2.27, 95% CI = 1.39-3.69).

CONCLUSIONS

In older adults with multiple chronic conditions, guideline-recommended medications for atrial fibrillation, coronary artery disease, depression, diabetes mellitus, and heart failure were largely not associated with self-reported decline in physical function, although there were associations for some medications in those with less polypharmacy.

Prehospital Delay in Older Adults with Acute Myocardial Infarction: The ComprehenSIVe Evaluation of Risk Factors in Older Patients with Acute Myocardial Infarction Study

BACKGROUND/OBJECTIVES

Timely administration of antiischemic therapies improves outcomes in individuals with acute myocardial infarction (AMI). Prior literature on delays in AMI care has largely focused on in-hospital delay ("door to balloon" time). Our objective was to identify factors associated with prehospital delay in a contemporary national cohort of older adults with AMI.

DESIGN

Cross-sectional analysis of data from the ComprehenSIVe Evaluation of Risk Factors in Older Patients with Acute Myocardial Infarction (SILVER-AMI) study, an observational study of older adults hospitalized for AMI.

SETTING

U.S. academic and community hospitals (N = 94).

PARTICIPANTS

Individuals aged 75 and older hospitalized for AMI (N = 2,500).

MEASUREMENTS

Prehospital delay was defined as symptom duration of 6 hours or longer before hospital presentation and was obtained according to participant or caregiver report during AMI hospitalization. Potential predictors of delay from demographic, clinical presentation, comorbid conditions, function, and social support domains were obtained through in-person assessment during the index hospitalization and medical record abstraction.

RESULTS

Nonwhite race (adjusted odds ratio (aOR) = 1.54, P = .002), atypical symptoms (aOR = 1.41, P = .001), and heart failure (HF) (aOR = 1.35, P = .006 for HF) were significantly associated with delay.

CONCLUSION

In contrast with younger AMI populations, female sex and diabetes mellitus were not associated with delay in this older cohort, but factors from other domains (nonwhite race, atypical symptoms, and HF) were significantly associated with delay. These results can be used to customize future public health efforts to encourage early presentation for older adults with AMI.

Imputation of Gait Speed for Noncompleters in the 400-Meter Walk: Application to the Lifestyle Interventions for Elders Study

When a 400-m walk test with time constraint (in 15 minutes) is administered, analysis of the associated 400-m gait speed can be challenging because some older adults are unable to complete the distance in time (noncompleters). A simplistic imputation method is to calculate the observed speeds of the noncompleters as the partially completed distance divided by the corresponding amount of elapsed time as an estimate of gait speed over the full 400-m distance. This common practice has not been validated to the best of our knowledge. We propose a Bayesian multiple imputation (MI) method to impute the unobserved 400-m gait speed for noncompleters. Briefly, MI is performed under the assumption that the unobserved 400-m gait speed of noncompleters is left-censored from a normal distribution. We illustrate the application of the Bayesian MI method using longitudinal data collected from the Lifestyle Interventions for Elders (LIFE) study. A simulation study was performed to assess the bias in estimation of the mean 400-m gait speed using both methods. The results indicate that the simplistic imputation method tends to overestimate the population mean, whereas the Bayesian MI method yields minimal bias as the sample size increases.

Contributions of COPD, asthma, and ten comorbid conditions to health care utilization and patient-centered outcomes among US adults with obstructive airway disease

Background

Among persons with obstructive airway disease, the relative contributions of chronic obstructive pulmonary disease (COPD), asthma, and common comorbid conditions to health care utilization and patient-centered outcomes (PCOs) have not been previously reported.

Methods

We followed a total of 3,486 persons aged ≥40 years with COPD, asthma, or both at baseline, from the Medical Expenditure Panel Survey (MEPS) cohorts enrolled annually from 2008 through 2012 for 1 year. MEPS is a prospective observational study of US households recording self-reported COPD, asthma, and ten medical conditions: angina, arthritis, cancer, coronary heart disease, cognitive impairment, diabetes, hypertension, lung cancer, myocardial infarction, and stroke/transient ischemic attack. We studied the separate contributions of these conditions to health care utilization (all-cause and respiratory disease hospitalization, any emergency department [ED] visit, and six or more outpatient visits) and PCOs (seven or more days spent in bed due to illness, incident loss of mobility, and incident decline in self-perceived health).

Results

COPD made the largest contributions to all-cause and respiratory disease hospitalization and ED visits, while arthritis made the largest contribution to outpatient health care. Arthritis and COPD, respectively, made the greatest contributions to the PCOs.

Conclusion

COPD made the largest and second largest contributions to health care utilization and PCOs among US adults with obstructive airway disease. The twelve medical conditions collectively accounted for between 52% and 61% of the health care utilization outcomes and between 53% and 68% of the PCOs. Cognitive impairment, diabetes, hypertension, and stroke also made significant contributions.

Intervention to Prevent Falls: Community-Based Clinics

PURPOSE

The purpose of this study was to document results of State funded fall prevention clinics on rates of self-reported falls and fall-related use of health services.

METHODS

Older adults participated in community-based fall prevention clinics providing individual assessments, interventions, and referrals to collaborating community providers. A pre-post design compares self-reported 6-month fall history and fall-related use of health care before and after clinic attendance.

RESULTS

Participants ( N = 751) were predominantly female (82%) averaging 81 years of age reporting vision (75%) and mobility (57%) difficulties. Assessments revealed polypharmacy (54%), moderate- to high-risk mobility issues (39%), and postural hypotension (10%). Self-reported preclinic fall rates were 256/751(34%) and postclinic rates were 81/751 (10.8%), ( p = .0001). Reported use of fall-related health services, including hospitalization, was also significantly lower after intervention.

IMPLICATIONS

Evidence-based assessments, risk-reducing recommendations, and referrals that include convenient exercise opportunities may reduce falls and utilization of health care services. Estimates regarding health care spending and policy are presented.

Factors Associated with Functional Recovery among Older Intensive Care Unit Survivors

RATIONALE

Most of the 1.4 million older adults who survive the intensive care unit (ICU) annually in the United States face increased disability, but little is known about those who achieve functional recovery.

OBJECTIVES

Our objectives were twofold: to evaluate the incidence and time to recovery of premorbid function within 6 months of a critical illness and to identify independent predictors of functional recovery among older ICU survivors.

METHODS

Potential participants included 754 persons aged 70 years or older who were evaluated monthly in 13 functional activities (1998-2012). The analytic sample included 218 ICU admissions from 186 ICU survivors. Functional recovery was defined as returning to a disability count less than or equal to the pre-ICU disability count within 6 months. Twenty-one potential predictors were evaluated for their associations with recovery.

MEASUREMENTS AND MAIN RESULTS

Functional recovery was observed for 114 (52.3%) of the 218 admissions. In multivariable analysis, higher body mass index (hazard ratio [HR], 1.07; 95% confidence interval [CI], 1.03-1.12) and greater functional self-efficacy (HR, 1.05; 95% CI, 1.02-1.08), a measure of confidence in performing various activities, were associated with recovery, whereas pre-ICU impairment in hearing (HR, 0.38; 95% CI, 0.22-0.66) and vision (HR, 0.59; 95% CI, 0.37-0.95) were associated with a lack of recovery.

CONCLUSIONS

Among older adults who survived an ICU admission with increased disability, pre-ICU hearing and vision impairment were strongly associated with poor functional recovery within 6 months, whereas higher body mass index and functional self-efficacy were associated with recovery. Future research is needed to evaluate whether interventions targeting these factors improve functional outcomes among older ICU survivors.