Neighborhood Socioeconomic Deprivation and Health Care Costs in Older Community-Dwelling Adults: Importance of Functional Impairment and Frailty.

BACKGROUND: Low neighborhood socioeconomic status is associated with adverse health outcomes, but its association with health care costs in older adults is uncertain. OBJECTIVES: To estimate the association of neighborhood Area Deprivation Index (ADI) with total, inpatient, outpatient, skilled nursing facility (SNF), and home health care (HHC) costs among older community-dwelling Medicare beneficiaries, and determine whether these associations are explained by multimorbidity, phenotypic frailty, or functional impairments. DESIGN: Four prospective cohort studies linked with each other and with Medicare claims. PARTICIPANTS: In total, 8165 community-dwelling fee-for-service beneficiaries (mean age 79.2 years, 52.9% female). MAIN MEASURES: ADI of participant residence census tract, Hierarchical Conditions Category multimorbidity score, self-reported functional impairments (difficulty performing four activities of daily living), and frailty phenotype. Total, inpatient, outpatient, post-acute SNF, and HHC costs (US 2020 dollars) for 36 months after the index examination. KEY RESULTS: Mean incremental annualized total health care costs adjusted for age, race/ethnicity, and sex increased with ADI ($3317 [95% CI 1274 to 5360] for the most deprived vs least deprived ADI quintile, and overall p-value for ADI variable 0.009). The incremental cost for the most deprived vs least deprived ADI quintile was increasingly attenuated after separate adjustment for multimorbidity ($2407 [95% CI 416 to 4398], overall ADI p-value 0.066), frailty phenotype ($1962 [95% CI 11 to 3913], overall ADI p-value 0.22), or functional impairments ($1246 [95% CI -706 to 3198], overall ADI p-value 0.29). CONCLUSIONS: Total health care costs are higher for older community-dwelling Medicare beneficiaries residing in the most socioeconomically deprived areas compared to the least deprived areas. This association was not significant after accounting for the higher prevalence of phenotypic frailty and functional impairments among residents of socioeconomically deprived neighborhoods.

Hip Fracture Risk Assessment Tools for Adults Aged 80 Years and Older.

Importance: While adults aged 80 years and older account for 70% of hip fractures in the US, performance of fracture risk assessment tools in this population is uncertain. Objective: To compare performance of the Fracture Risk Assessment Tool (FRAX), Garvan Fracture Risk Calculator, and femoral neck bone mineral density (FNBMD) alone in 5-year hip fracture prediction. Design, Setting and Participants: Prognostic analysis of 3 prospective cohort studies including participants attending an index examination (1997 to 2016) at age 80 years or older. Data were analyzed from March 2023 to April 2024. Main Outcomes and Measures: Participants contacted every 4 or 6 months after index examination to ascertain incident hip fractures and vital status. Predicted 5-year hip fracture probabilities calculated using FRAX and Garvan models incorporating FNBMD and FNBMD alone. Model discrimination assessed by area under receiver operating characteristic curve (AUC). Model calibration assessed by comparing observed vs predicted hip fracture probabilities within predicted risk quintiles. Results: A total of 8890 participants were included, with a mean (SD) age at index examination of 82.6 (2.7) years; 4906 participants (55.2%) were women, 866 (9.7%) were Black, 7836 (88.1%) were White, and 188 (2.1%) were other races and ethnicities. During 5-year follow-up, 321 women (6.5%) and 123 men (3.1%) experienced a hip fracture; 818 women (16.7%) and 921 men (23.1%) died before hip fracture. Among women, AUC was 0.69 (95% CI, 0.67-0.72) for FRAX, 0.69 (95% CI, 0.66-0.72) for Garvan, and 0.72 (95% CI, 0.69-0.75) for FNBMD alone (FNBMD superior to FRAX, P = .01; and Garvan, P = .01). Among men, AUC was 0.71 (95% CI, 0.66-0.75) for FRAX, 0.76 (95% CI, 0.72-0.81) for Garvan, and 0.77 (95% CI, 0.72-0.81) for FNBMD alone (P < .001 Garvan and FNBMD alone superior to FRAX). Among both sexes, Garvan greatly overestimated hip fracture risk among individuals in upper quintiles of predicted risk, while FRAX modestly underestimated risk among those in intermediate quintiles of predicted risk. Conclusions and Relevance: In this prognostic study of adults aged 80 years and older, FRAX and Garvan tools incorporating FNBMD compared with FNBMD alone did not improve 5-year hip fracture discrimination. FRAX modestly underpredicted observed hip fracture probability in intermediate-risk individuals. Garvan markedly overpredicted observed hip fracture probability in high-risk individuals. Until better prediction tools are available, clinicians should prioritize consideration of hip BMD, life expectancy, and patient preferences in decision-making regarding drug treatment initiation for hip fracture prevention in late-life adults.

Skeletal Muscle Energetics Explain the Sex Disparity in Mobility Impairment in the Study of Muscle, Mobility and Aging.

The age-related decline in muscle mitochondrial energetics contributes to the loss of mobility in older adults. Women experience a higher prevalence of mobility impairment compared to men, but it is unknown whether sex-specific differences in muscle energetics underlie this disparity. In the Study of Muscle, Mobility and Aging (SOMMA), muscle energetics were characterized using in vivo phosphorus-31 magnetic resonance spectroscopy and high-resolution respirometry of vastus lateralis biopsies in 773 participants (56.4% women, age 70-94 years). A Short Physical Performance Battery (SPPB) score ≤8 was used to define lower-extremity mobility impairment. Muscle mitochondrial energetics were lower in women compared to men (eg, Maximal Complex I&II OXPHOS: Women = 55.06 ± 15.95; Men = 65.80 ± 19.74; p < .001) and in individuals with mobility impairment compared to those without (eg, Maximal Complex I&II OXPHOS in women: SPPB ≥ 9 = 56.59 ± 16.22; SPPB ≤ 8 = 47.37 ± 11.85; p < .001). Muscle energetics were negatively associated with age only in men (eg, Maximal ETS capacity: R = -0.15, p = .02; age/sex interaction, p = .04), resulting in muscle energetics measures that were significantly lower in women than men in the 70-79 age group but not the 80+ age group. Similarly, the odds of mobility impairment were greater in women than men only in the 70-79 age group (70-79 age group, odds ratio [OR]age-adjusted = 1.78, 95% confidence interval [CI] = 1.03, 3.08, p = .038; 80+ age group, ORage-adjusted = 1.05, 95% CI = 0.52, 2.15, p = .89). Accounting for muscle energetics attenuated up to 75% of the greater odds of mobility impairment in women. Women had lower muscle mitochondrial energetics compared to men, which largely explain their greater odds of lower-extremity mobility impairment.

Skeletal muscle energetics explain the sex disparity in mobility impairment in the Study of Muscle, Mobility and Aging (SOMMA).

The age-related decline in muscle mitochondrial energetics contributes to the loss of mobility in older adults. Women experience a higher prevalence of mobility impairment compared to men, but it is unknown whether sex-specific differences in muscle energetics underlie this disparity. In the Study of Muscle, Mobility and Aging (SOMMA), muscle energetics were characterized using in vivo phosphorus-31 magnetic resonance spectroscopy and high-resolution respirometry of vastus lateralis biopsies in 773 participants (56.4% women, age 70-94 years). A Short Physical Performance Battery score ≤ 8 was used to define lower-extremity mobility impairment. Muscle mitochondrial energetics were lower in women compared to men (e.g. Maximal Complex I&II OXPHOS: Women=55.06 +/- 15.95; Men=65.80 +/- 19.74; p<0.001) and in individuals with mobility impairment compared to those without (e.g., Maximal Complex I&II OXPHOS in women: SPPB≥9=56.59 +/- 16.22; SPPB≤8=47.37 +/- 11.85; p<0.001). Muscle energetics were negatively associated with age only in men (e.g., Maximal ETS capacity: R=-0.15, p=0.02; age/sex interaction, p=0.04), resulting in muscle energetics measures that were significantly lower in women than men in the 70-79 age group but not the 80+ age group. Similarly, the odds of mobility impairment were greater in women than men only in the 70-79 age group (70-79 age group, OR age-adjusted =1.78, 95% CI=1.03, 3.08, p=0.038; 80+ age group, OR age-adjusted =1.05, 95% CI=0.52, 2.15, p=0.89). Accounting for muscle energetics attenuated up to 75% of the greater odds of mobility impairment in women. Women had lower muscle mitochondrial energetics compared to men, which largely explain their greater odds of lower-extremity mobility impairment.

Application of the D3 -creatine muscle mass assessment tool to a geriatric weight loss trial: A pilot study.

BACKGROUND: Traditionally, weight loss (WL) trials utilize dual energy X-ray absorptiometry (DXA) to measure lean mass. This method assumes lean mass, as the sum of all non-bone and non-fat tissue, is a reasonable proxy for muscle mass. In contrast, the D3 -creatine (D3 Cr) dilution method directly measures whole body skeletal muscle mass, although this method has yet to be applied in the context of a geriatric WL trial. The purpose of this project was to (1) describe estimates of change and variability in D3 Cr muscle mass in older adults participating in an intentional WL intervention and (2) relate its change to other measures of body composition as well as muscle function and strength. METHODS: The INVEST in Bone Health trial (NCT04076618), used as a scaffold for this ancillary pilot project, is a three-armed, 12-month randomized, controlled trial designed to determine the effects of resistance training or weighted vest use during intentional WL on a battery of musculoskeletal health outcomes among 150 older adults living with obesity. A convenience sample of 24 participants (n = 8/arm) are included in this analysis. At baseline and 6 months, participants were weighed, ingested a 30 mg D3 Cr tracer dose, provided a fasted urine sample 3-6 days post-dosage, underwent DXA (total body fat and lean masses, appendicular lean mass) and computed tomography (mid-thigh and trunk muscle/intermuscular fat areas) scans, and performed 400-m walk, stair climb, knee extensor strength, and grip strength tests. RESULTS: Participants were older (68.0 ± 4.4 years), mostly White (75.0%), predominantly female (66.7%), and living with obesity (body mass index: 33.8 ± 2.7 kg/m2 ). Six month total body WL was -10.3 (95% confidence interval, CI: -12.7, -7.9) kg. All DXA and computed tomography-derived body composition measures were significantly decreased from baseline, yet D3 Cr muscle mass did not change [+0.5 (95% CI: -2.0, 3.0) kg]. Of muscle function and strength measures, only grip strength significantly changed [+2.5 (95% CI: 1.0, 4.0) kg] from baseline. CONCLUSIONS: Among 24 older adults, significant WL with or without weighted vest use or resistance training over a 6-month period was associated with significant declines in all bioimaging metrics, while D3 Cr muscle mass and muscle function and strength were preserved. Treatment assignment for the trial remains blinded; therefore, full interpretation of these findings is limited. Future work in this area will assess change in D3 Cr muscle mass by parent trial treatment group assignment in all study participants.

Linoleic Acid Intake and Physical Function: Pilot Results from the Health ABC Energy Expenditure Sub-Study.

Background: Dietary fat quality is important for health and physical functioning in older adults. Linoleic acid is a dietary polyunsaturated fatty acid that is necessary for optimal inner-mitochondrial membrane function. However, limited evidence exists for examining the role of linoleic acid intake on indices of mobility and physical function. In this pilot study, we sought to examine the associations between linoleic acid intake and physical functioning in older adults. Methods: This secondary analysis of data from the Health, Aging, and Body Composition energy expenditure sub-study was conducted for our investigation. Ability to complete physical tasks such as climbing a flight of stairs, walking a quarter mile, and lifting 10 lbs. was self-reported. Daily linoleic acid intake was estimated from a food frequency questionnaire. Persons with daily linoleic acid intake below approximately 85% of Adequate Intake were considered as having low linoleic acid intake. Covariate-adjusted logistic models were used for the analyses. Results: The final analytical sample included 317 participants aged 74.4 ± 2.8 years who consumed 18.9 ± 11.4 g/day of linoleic acid, with 78 (24.6%) participants having low daily linoleic acid intake. Persons with low daily linoleic acid intake had 2.58 (95% confidence interval: 1.27-5.24) greater odds for a limitation in climbing stairs. Conclusions: Our pilot investigation found that low daily linoleic acid intake could be associated with physical function in older adults. Dietitians working with older patients may want to consider the importance of daily linoleic acid intake for health and certain physical function tasks.

Subjective social status moderates back pain and mental health in older men.

OBJECTIVES: Back pain and poor mental health are interrelated issues in older men. Evidence suggests that socioeconomic status moderates this relationship, but less is known about the role of subjective social status (SSS). This study examined if the association between back pain and mental health is moderated by SSS. METHOD: We used a sample of community-dwelling older men (≥65 years) from the Osteoporotic Fractures in Men Study (N = 5994). Participants self-reported their back pain severity and frequency over the past 12 months. SSS was assessed with the MacArthur Scale of SSS. Mental health was assessed with the SF-12 Mental Component Summary (MCS). RESULTS: Severe back pain was associated with lower SF-12 MCS scores (p = .03). Back pain frequency was not associated with SF-12 MCS scores. SSS moderated the back pain and mental health relationship. Among men with higher national or community SSS, the association between back pain severity and SF-12 MCS scores was not significant. However, among men with lower national or community SSS, more severe back pain was associated with lower SF-12 MCS scores (p's < .001). Among those with lower national or community SSS, greater back pain frequency was also associated with lower SF-12 MCS scores (p's < .05). CONCLUSION: Where one ranks oneself within their nation or community matters for the back pain and mental health relationship. Higher SSS may be a psychosocial resource that buffers the negative associations of severe and frequent back pain on mental health in older men.

Life-space mobility and healthcare costs and utilization in older men.

OBJECTIVES: To determine the association of life-space score with subsequent healthcare costs and utilization. DESIGN: Prospective cohort study (Osteoporotic Fracture in Men [MrOS]). SETTING: Six U.S. sites. PARTICIPANTS: A total of 1555 community-dwelling men (mean age 79.3 years; 91.5% white, non-Hispanic) participating in the MrOS Year 7 (Y7) examination linked with their Medicare claims data. MEASUREMENTS: Life-space during the past month was assessed as 0 (daily restriction to one's bedroom) to 120 (daily trips outside one's town without assistance) and categorized (0-40, 41-60, 61-80, 81-100, 101-120). Total annualized direct healthcare costs and utilization were ascertained during 36 months after the Y7 examination. RESULTS: Mean total annualized costs (2020 U.S. dollars) steadily increased across category of life-space score, from $7954 (standard deviation [SD] 16,576) among men with life-space scores of 101-120 to $26,430 (SD 28,433) among men with life-space scores of 0-40 (p < 0.001). After adjustment for demographics, men with a life-space score of 0-40 versus men with a life-space score of 101-120 had greater mean total costs (cost ratio [CR] = 2.52; 95% confidence interval [CI] = 1.84-3.45) and greater risk of subsequent hospitalization (odds ratio [OR] 4.72, 95% CI 2.61-8.53) and skilled nursing facility (SNF) stay (OR 7.32, 95% CI 3.65-14.66). Life-space score was no longer significantly associated with total healthcare costs (CR for 0-40 vs 101-120 1.29; 95% CI 0.91-1.84) and hospitalization (OR 1.76, 95% CI 0.89-3.51) after simultaneous consideration of demographics, medical factors, self-reported health and function, and the frailty phenotype; the association of life-space with SNF stay remained significant (OR 2.86, 95% CI 1.26-6.49). CONCLUSION: Our results highlight the importance of function and mobility in predicting future healthcare costs and suggest the simple and convenient life-space score may in part capture risks from major geriatric domains and improve identification of older, community-dwelling men likely to require costly care.

Life course trauma and muscle weakness in older adults by gender and race/ethnicity: Results from the U.S. health and Retirement Study.

Muscle weakness, as measured by handgrip strength, is a primary determinant of physical functioning and disability. There is a high burden of muscle weakness in the United States with close to 50 percent of older Americans meeting criteria for clinical muscle weakness. While previous racial/ethnic disparities have been documented among older adults, the extent to which lifecourse trauma shapes muscle strength trajectories is unknown. Using U.S. Health and Retirement Study (N = 20,472, Mean Age = 63.8 years) data on grip strength (2006-2014, up to 3 assessments) and retrospectively reported traumatic events, we fit gender-stratified growth curve models to investigate whether traumatic events experienced across the lifecourse or at distinct sensitive periods (childhood, early/emerging adulthood or mid-life) predicted later-life trajectories of grip strength. There was no association between cumulative trauma and trajectories of grip strength and the main effects for the life stage models were largely null. However, among White women, our results suggest that traumatic events experienced during childhood (ß = -0.012; 95% CI = -0.024, 0.0004) compared to middle adulthood are associated with faster declines in grip strength in later life. Traumatic events reported during childhood was related to a slower decline in grip strength over time among Hispanic women compared to that for White women (ß = 0.086, 95% CI = 0.044, 0.128). Among Black men, the association between traumatic events during early/emerging adulthood and age-related declines in grip strength was stronger for Black men than for White men (interaction ß = -0.070; 95% CI = -0.138, 0.001). Traumatic events experienced during distinct life stages may influence later life declines in grip strength and exacerbate racial inequalities in later life. This study addresses an important gap by investigating the life course social determinants of later life muscle strength, which is a key driver of physical functioning and mobility.

Frailty Phenotype and Healthcare Costs and Utilization in Older Men.

OBJECTIVES: To determine the association of the frailty phenotype with subsequent healthcare costs and utilization. DESIGN: Prospective cohort study (Osteoporotic Fracture in Men [MrOS]). SETTING: Six US sites. PARTICIPANTS: A total of 1,514 community-dwelling men (mean age = 79.3 years) participating in the MrOS Year 7 (Y7) examination linked with their Medicare claims data. MEASUREMENTS: At Y7, the frailty phenotype was operationalized using five components and categorized as robust, pre-frail, or frail. Multimorbidity and a frailty indicator (approximating the deficit accumulation index) were derived from claims data. Functional limitations were assessed by asking about difficulty performing instrumental activities of daily living. Total direct healthcare costs and utilization were ascertained during 36 months following Y7. RESULTS: Mean of total annualized costs (2018 dollars) was $5,707 (standard deviation [SD] = 8,800) among robust, $8,964 (SD = 18,156) among pre-frail, and $20,027 (SD = 27,419) among frail men. Compared with robust men, frail men (cost ratio [CR] = 2.35; 95% confidence interval [CI] = 1.88-2.93) and pre-frail men (CR = 1.28; 95% CI = 1.11-1.48) incurred greater total costs after adjustment for demographics, multimorbidity, and cognitive function. Associations of phenotypic pre-frailty and frailty with higher total costs were somewhat attenuated but persisted after further consideration of functional limitations and a claims-based frailty indicator. Each individual frailty component was also associated with higher total costs. Frail vs robust men had higher odds of hospitalization (odds ratio [OR] = 2.62; 95% CI = 1.75-3.91) and skilled nursing facility (SNF) stay (OR = 3.36; 95% CI = 1.83-6.20). A smaller but significant effect of the pre-frail category on SNF stay was present. CONCLUSION: Phenotypic pre-frailty and frailty were associated with higher subsequent total healthcare costs in older community-dwelling men after accounting for a claims-based frailty indicator, functional limitations, multimorbidity, cognitive impairment, and demographics. Assessment of the frailty phenotype or individual components such as slowness may improve identification of older community-dwelling adults at risk for costly extensive care.

D3 -Creatine dilution and the importance of accuracy in the assessment of skeletal muscle mass.

Sarcopenia has been described as the age-associated decrease in skeletal muscle mass. However, virtually every study of sarcopenia has measured lean body mass (LBM) or fat free mass (FFM) rather than muscle mass, specifically. In a number of published sarcopenia studies, LBM or FFM is referred to as muscle mass, leading to an incorrect assumption that measuring LBM or FFM is an accurate measure of muscle mass. As a result, the data on the effects of changes in LBM or FFM in older populations on outcomes such as functional capacity, disability, and risk of injurious falls have been inconsistent resulting in the conclusion that muscle mass is only weakly related to these outcomes. We review and describe the assumptions for the most commonly used measurements of body composition. Dual-energy X-ray absorptiometry (DXA) has become an increasingly common tool for the assessment of LBM or FFM and appendicular lean mass as a surrogate, but inaccurate, measurement of muscle mass. Other previously used methods (total body water, bioelectric impedance, and imaging) also have significant limitations. D3 -Creatine (D3 -Cr) dilution provides a direct and accurate measurement of creatine pool size and skeletal muscle mass. In a recent study in older men (MrOS cohort), D3 -Cr muscle mass was associated with functional capacity and risk of injurious falls and disability, while assessments of LBM or appendicular lean mass by DXA were only weakly or not associated with these outcomes. Inaccurate measurements of muscle mass by DXA and other methods have led to inconsistent results and potentially erroneous conclusions about the importance of skeletal muscle mass in health and disease. The assessment of skeletal muscle mass using the D3 -Cr dilution method in prospective cohort studies may reveal sarcopenia as a powerful risk factor for late life disability and chronic disease.

The Association Between Objectively Measured Physical Activity and Subsequent Health Care Utilization in Older Men.

BACKGROUND: To examine the associations between objective physical activity measures and subsequent health care utilization. METHODS: We studied 1,283 men (mean age 79.1 years, SD 5.3) participating in the Osteoporotic Fractures in Men Study. Participants wore a SenseWear® Pro Armband monitor for 1 week. Data was summarized as daily (i) step counts, (ii) total energy expenditure, (iii) active energy expenditure, and (iv) activity time (sedentary, ≥ light, ≥ moderate). The outcome measures of 1-year hospitalizations/duration of stay from Medicare data were analyzed with a two-part hurdle model. Covariates included age, clinical center, body mass index, marital status, depressive symptoms, medical conditions, cognitive function, and prior hospitalization. RESULTS: Each 1 SD = 3,092 step increase in daily step count was associated with a 34% (95% confidence interval [CI]: 19%-46%) lower odds of hospitalization in base model (age and center) and 21% (95% CI: 4%-35%) lower odds of hospitalization in fully adjusted models. Similar but smaller associations held for other physical activity measures, but these associations were not significant in fully adjusted models. Among those hospitalized, higher step count was associated with shorter total duration of acute/postacute care stays in the base model only. There was a fourfold significant difference (from model-based estimates) in predicted care days comparing those with 2,000 versus 10,000 daily steps in the base model, but only a twofold difference (not significant) in the full model. CONCLUSION: Daily step count is an easily determined measure of physical activity that may be useful in assessment of future health care burden in older men.

Frailty Phenotype and Healthcare Costs and Utilization in Older Women.

OBJECTIVES: To determine the association of the frailty phenotype with subsequent healthcare costs and utilization. DESIGN: Prospective cohort study (Study of Osteoporotic Fractures (SOF)). SETTING: Four U.S. sites. PARTICIPANTS: Community-dwelling women (mean age 80.2) participating in SOF Year 10 (Y10) examination linked with their Medicare claims data (N=2,150). MEASUREMENTS: At Y10, frailty phenotype defined using criteria similar to those used in the Cardiovascular Health Study frailty phenotype and categorized as robust, intermediate stage, or frail. Participant multimorbidity burden ascertained using claims data. Functional limitations assessed by asking about difficulty performing instrumental activities of daily living. Total direct healthcare costs and utilization ascertained during 12 months after Y10. RESULTS: Mean total annualized cost±standard deviation (2014 dollars) was $3,781±6,920 for robust women, $6,632±12,452 for intermediate stage women, and $10,755 ± 16,589 for frail women. After adjustment for age, site, multimorbidity burden, and cognition, frail women had greater mean total (cost ratio (CR)=1.91, 95% confidence interval (CI)=1.59-2.31) and outpatient (CR=1.55, 95% CI=1.36-1.78) costs than robust women and greater odds of hospitalization (odds ratio (OR)=2.05, 95% CI=1.47-2.87) and a skilled nursing facility stay (OR=3.85, 95% CI=1.88-7.88). There were smaller but significant effects of the intermediate stage category on these outcomes. Individual frailty components (shrinking, poor energy, slowness, low physical activity) were also each associated with higher total costs. Functional limitations partially mediated the association between the frailty phenotype and total costs (CR further adjusted for self-reported limitations=1.32, 95% CI=1.07-1.63 for frail vs robust; CR=1.35, 95% CI=1.18-1.55 for intermediate stage vs robust women). CONCLUSION: Intermediate stage and frail older community-dwelling women had higher subsequent total healthcare costs and utilization after accounting for multimorbidity and functional limitations. Frailty phenotype assessment may improve identification of older adults likely to require costly, extensive care.

Effects of Mobility and Multimorbidity on Inpatient and Postacute Health Care Utilization.

Background: This study examines effects of mobility and multimorbidity on hospitalization and inpatient and postacute care (PAC) facility days among older men. Methods: Prospective study of 1,701 men (mean age 79.3 years) participating in Osteoporotic Fractures in Men (MrOS) Study Year 7 (Y7) examination (2007-2008) linked with their Medicare claims. At Y7, mobility ascertained by usual gait speed and categorized as poor, intermediate, or good. Multimorbidity quantified by applying Elixhauser algorithm to inpatient and outpatient claims and categorized as none, mild-moderate, or high. Hospitalizations and PAC facility stays ascertained during 12 months following Y7. Results: Reduced mobility and greater multimorbidity burden were independently associated with a higher risk of inpatient and PAC facility utilization, after accounting for each other and traditional indicators. Adjusted mean total facility days per year were 1.13 (95% confidence interval [CI] = 0.74-1.40) among men with good mobility increasing to 2.43 (95% CI = 1.17-3.84) among men with poor mobility, and 0.67 (95% CI = 0.38-0.91) among men without multimorbidity increasing to 2.70 (95% CI = 1.58-3.77) among men with high multimorbidity. Men with poor mobility and high multimorbidity had a ninefold increase in mean total facility days per year (5.50, 95% CI = 2.78-10.87) compared with men with good mobility without multimorbidity (0.59, 95% CI = 0.37-0.95). Conclusions: Among older men, mobility limitations and multimorbidity were independent predictors of higher inpatient and PAC utilization after considering each other and conventional predictors. Marked combined effects of reduced mobility and multimorbidity burden may be important to consider in clinical decision-making and planning health care delivery strategies for the growing aged population.

Correction to: Comparison of fracture risk assessment tools in older men without prior hip or spine fracture: the MrOS study.

Owing to an oversight by the authors, the acknowledgments were incomplete.

Comparison of fracture risk assessment tools in older men without prior hip or spine fracture: the MrOS study.

Femoral neck bone mineral density (BMD), age plus femoral neck BMD T score, and three externally generated fracture risk tools had similar accuracy to identify older men who developed osteoporotic fractures. Risk tools with femoral neck BMD performed better than those without BMD. The externally developed risk tools were poorly calibrated. INTRODUCTION: We compared the performance of fracture risk assessment tools in older men, accounting for competing risks including mortality. METHODS: A comparative ROC curve analysis assessed the ability of the QFracture, FRAX® and Garvan fracture risk tools, and femoral neck bone mineral density (BMD) T score with or without age to identify incident fracture in community-dwelling men aged 65 years or older (N = 4994) without hip or clinical vertebral fracture or antifracture treatment at baseline. RESULTS: Among risk tools calculated with BMD, the discriminative ability to identify men with incident hip fracture was similar for FRAX (AUC 0.77, 95% CI 0.73, 0.81), the Garvan tool (AUC 0.78, 95% CI 0.74, 0.82), age plus femoral neck BMD T score (AUC 0.79, 95% CI 0.75, 0.83), and femoral neck BMD T score alone (AUC 0.76, 95% CI 0.72, 0.81). Among risk tools calculated without BMD, the discriminative ability to identify hip fracture was similar for QFracture (AUC 0.69, 95% CI 0.66, 0.73), FRAX (AUC 0.70, 95% CI 0.66, 0.73), and the Garvan tool (AUC 0.71, 95% CI 0.67, 0.74). Correlated ROC curve analyses revealed better diagnostic accuracy for risk scores calculated with BMD compared with QFracture (P < 0.0001). Calibration was good for the internally generated BMD T score predictor with or without age and poor for the externally developed risk tools. CONCLUSION: In untreated older men without fragility fractures at baseline, an age plus femoral neck BMD T score classifier identified men with incident hip fracture as accurately as more complicated fracture risk scores.

Cystatin C and the Risk of Frailty and Mortality in Older Men.

BACKGROUND: This study examines the association between cystatin C (cysC) levels and risks of progression of frailty status or death in older men. METHODS: Prospective study of 2,613 men without overt frailty aged 67 years and older enrolled in the MrOS ancillary sleep study. Baseline measurements included serum cysC, serum creatinine, and frailty status. Repeat frailty status, performed an average of 3.4 years later, was assessed as an ordinal outcome of robust, intermediate stage (prefrail), frail or dead. RESULTS: Mean age was 75.7 years. Men with higher cysC were older and had a higher comorbidity burden. After adjusting for age, clinical site, and race, higher cysC was associated with nearly twofold greater odds of being classified as intermediate stage versus robust (OR quartile 4 vs 1; 1.82, 95% confidence interval [CI] 1.35-2.45), a threefold greater odds of frailty versus robust (OR quartile 4 vs 1; 3.13, 95% CI 2.03-4.82), and a more than fivefold greater odds of death versus robust (OR quartile 4 vs 1; 5.48, 95% CI 2.98-10.08). Results were similar for cysC-based estimated glomerular filtration rate (eGFR). This relationship was attenuated but persisted after adjusting for additional potential confounders including baseline frailty status, body mass index, smoking status, comorbidity burden, self-reported disability, and serum albumin. In contrast, neither serum creatinine nor creatinine-based eGFR was associated in a graded manner with higher risks of development of frailty or death. CONCLUSIONS: In this cohort of older men without overt frailty, higher cysC and cysC-based eGFR, but not creatinine or creatinine-based estimates of GFR, were associated with increased risks of frailty or death. These findings suggest that higher cysC level may be a promising biomarker for unsuccessful aging as manifested by increased risks of frailty and death.

Assessment of Lean Mass and Physical Performance in Sarcopenia.

This review provides a description of the assessment of lean mass and physical performance with particular attention to how these measures are used in the context of sarcopenia, in both research and clinical settings. One of the most common methods to estimate muscle mass is whole-body dual-energy X-ray absorptiometry (DXA). DXA estimates the total amount of lean tissue but does not directly measure muscle mass. Appendicular lean mass (ALM), derived from DXA scans, is the sum of the lean tissue in the arms and legs. ALM alone, or scaled to height squared (ALM/height(2)) or body mass index (ALM/body mass index), is the most common metric used as an approximation of muscle mass in sarcopenia research. Other methods to assess muscle mass include central or peripheral quantitative computed tomography (to determine muscle cross-sectional area and muscle density, a marker of fat i nfiltration into the muscle); magnetic resonance (to assess muscle cross-sectional area and volume); and bioelectrical impedance analysis (to determine fat-free mass). Many approaches to objectively measuring physical performance have been used in sarcopenia research. Muscle strength is often measured: Grip strength is very inexpensive and straightforward to assess, whereas assessment of lower extremity strength is more difficult. However, lower extremity strength may be a more relevant measure than grip strength in the context of mobility outcomes. Dynamic physical performance is also widely measured in research settings and may be emerging as a routine assessment in clinical care. The most widely used measure of physical performance is walking speed over a short distance, usually 3-6 m. Other measures of objective physical performance include the Short Physical Performance Battery that includes gait speed, ability and time to rise from a chair 5 times, and static balance tests; and the Timed Up and Go test that measures the time to rise from a chair and walk a short distance. Finally, longer distance walking tests are also used. "Fast" versions of these tests measure either distance traveled in a set amount of time (as for the 6-minute walk test) or time to walk a set distance (such as the fast long distance corridor walk more than 400 m). The "usual pace" version of the longer distance walking test, the usual-pace 400 m walk, is an objective measure of disability and has been used as an outcome in clinical trials. In summary, there are many methods available to assess muscle mass and physical function, each with advantages and limitations. The choice of what test to use depends on the nature of the research question or the clinical environment and the availability of resources for evaluation.

Objective assessment of activity, energy expenditure, and functional limitations in older men: the Osteoporotic Fractures in Men study.

BACKGROUND: The relationship between objectively assessed activity, energy expenditure, and the development of functional limitations is unknown. METHODS: Energy expenditure and activity levels were measured objectively using the multisensor SenseWear Pro Armband worn for greater than or equal to 5 days in 1,983 MrOS men (aged ≥ 78.3 years) free of functional limitations. Validated algorithms calculated energy expenditure; standard cut points defined moderate or greater activity (≥ 3.0 METS); and sedentary behavior (time awake ≤ 1.5 METS). Self-reported functional limitation was determined at the activity assessment and 2.0 years later as inability to perform instrumental activities of daily living (managing money, managing medications, shopping, housework, and meal preparation) and activities of daily living (climb stairs, walk two to three blocks, transfer, or bathe). RESULTS: Each standard deviation decrease in total energy expenditure (420.6 kcal/day) increased the likelihood of inability to perform an instrumental activity of daily living (multivariate odds ratio [mOR]: 1.61, 95% CI: 1.30-2.00) or activity of daily living (mOR: 1.35, 95% CI: 1.12-1.63). Each standard deviation decrease in moderate or greater activity (61.1 minutes/day) increased the likelihood of inability to perform an instrumental activity of daily living (mOR: 1.47, 95% CI: 1.22-1.78) or activity of daily living (mOR: 1.36, 95% CI: 1.14-1.61). Each standard deviation increase in minutes of sedentary behavior (105.2 minutes/day) increased the likelihood of inability to perform an instrumental activity of daily living (mOR: 1.20, 95% CI: 1.03-1.40) or activity of daily living (mOR: 1.17, 95% CI: 1.01-1.35). CONCLUSION: Older men with lower total energy expenditure, lower moderate activity, or greater sedentary time were more likely to develop a functional limitation.