Dawn E. Alley

The FNIH Sarcopenia Project: Rationale, Study Description, Conference Recommendations, and Final Estimates

Background. Low muscle mass and weakness are common and potentially disabling in older adults, but in order to become recognized as a clinical condition, criteria for diagnosis should be based on clinically relevant thresholds and independently validated. The Foundation for the National Institutes of Health Biomarkers Consortium Sarcopenia Project used an evidence-based approach to develop these criteria. Initial findings were presented at a conference in May 2012, which generated recommendations that guided additional analyses to determine final recommended criteria. Details of the Project and its findings are presented in four accompanying manuscripts. Methods. The Foundation for the National Institutes of Health Sarcopenia Project used data from nine sources of community-dwelling older persons: Age, Gene/Environment Susceptibility-Reykjavik Study, Boston Puerto Rican Health Study, a series of six clinical trials, Framingham Heart Study, Health, Aging, and Body Composition, Invecchiare in Chianti, Osteoporotic Fractures in Men Study, Rancho Bernardo Study, and Study of Osteoporotic Fractures. Feedback from conference attendees was obtained via surveys and breakout groups. Results. The pooled sample included 26,625 participants (57% women, mean age in men 75.2 [±6.1 SD] and in women 78.6 [±5.9] years). Conference attendees emphasized the importance of evaluating the influence of body mass on cutpoints. Based on the analyses presented in this series, the final recommended cutpoints for weakness are grip strength <26kg for men and <16kg for women, and for low lean mass, appendicular lean mass adjusted for body mass index <0.789 for men and <0.512 for women. Conclusions. These evidence-based cutpoints, based on a large and diverse population, may help identify participants for clinical trials and should be evaluated among populations with high rates of functional limitations.

Hispanic Paradox in Biological Risk Profiles

OBJECTIVES We examined biological risk profiles by race, ethnicity, and nativity to evaluate evidence for a Hispanic paradox in measured health indicators. METHODS We used data on adults aged 40 years and older (n = 4206) from the National Health and Nutrition Examination Surveys (1999-2002) to compare blood pressure, metabolic, and inflammatory risk profiles for Whites, Blacks, US-born and foreign-born Hispanics, and Hispanics of Mexican origin. We controlled for age, gender, and socioeconomic status. RESULTS Hispanics have more risk factors above clinical risk levels than do Whites but fewer than Blacks. Differences between Hispanics and Whites disappeared after we controlled for socioeconomic status, but results differed by nativity. After we controlled for socioeconomic status, the differences between foreign-born Hispanics and Whites were eliminated, but US-born Mexican Americans still had higher biological risk scores than did both Whites and foreign-born Mexican Americans. CONCLUSIONS There is no Hispanic paradox in biological risk profiles. However, our finding that foreign-born Hispanics and Whites had similar biological risk profiles, but US-born Mexican Americans had higher risk, was consistent with hypothesized effects of migrant health selectivity (healthy people in-migrating and unhealthy people out-migrating) as well as some differences in health behaviors between US-born and foreign-born Hispanics.

An Evidence-Based Comparison of Operational Criteria for the Presence of Sarcopenia

Background. Several consensus groups have previously published operational criteria for sarcopenia, incorporating lean mass with strength and/or physical performance. The purpose of this manuscript is to describe the prevalence, agreement, and discrepancies between the Foundation for the National Institutes of Health (FNIH) criteria with other operational definitions for sarcopenia. Methods. The FNIH Sarcopenia Project used data from nine studies including: Age, Gene and Environment Susceptibility-Reykjavik Study; Boston Puerto Rican Health Study; a series of six clinical trials from the University of Connecticut; Framingham Heart Study; Health, Aging, and Body Composition Study; Invecchiare in Chianti; Osteoporotic Fractures in Men Study; Rancho Bernardo Study; and Study of Osteoporotic Fractures. Participants included in these analyses were aged 65 and older and had measures of body mass index, appendicular lean mass, grip strength, and gait speed. Results. The prevalence of sarcopenia and agreement proportions was higher in women than men. The lowest prevalence was observed with the FNIH criteria (1.3% men and 2.3% women) compared with the International Working Group and the European Working Group for Sarcopenia in Older Persons (5.1% and 5.3% in men and 11.8% and 13.3% in women, respectively). The positive percent agreements between the FNIH criteria and other criteria were low, ranging from 7% to 32% in men and 5% to 19% in women. However, the negative percent agreement were high (all >95%). Conclusions. The FNIH criteria result in a more conservative operational definition of sarcopenia, and the prevalence was lower compared with other proposed criteria. Agreement for diagnosing sarcopenia was low, but agreement for ruling out sarcopenia was very high. Consensus on the operational criteria for the diagnosis of sarcopenia is much needed to characterize populations for study and to identify adults for treatment.

Criteria for Clinically Relevant Weakness and Low Lean Mass and Their Longitudinal Association With Incident Mobility Impairment and Mortality: The Foundation for the National Institutes of Health (FNIH) Sarcopenia Project

Background. This analysis sought to determine the associations of the Foundation for the National Institutes of Health Sarcopenia Project criteria for weakness and low lean mass with likelihood for mobility impairment (gait speed ≤ 0.8 m/s) and mortality. Providing validity for these criteria is essential for research and clinical evaluation. Methods. Among 4,411 men and 1,869 women pooled from 6 cohort studies, 3-year likelihood for incident mobility impairment and mortality over 10 years were determined for individuals with weakness, low lean mass, and for those having both. Weakness was defined as low grip strength (<26kg men and <16kg women) and low grip strength-to-body mass index (BMI; kg/m2) ratio (<1.00 men and <0.56 women). Low lean mass (dual-energy x-ray absorptiometry) was categorized as low appendicular lean mass (ALM; <19.75kg men and <15.02kg women) and low ALM-to-BMI ratio (<0.789 men and <0.512 women). Results. Low grip strength (men: odds ratio [OR] = 2.31, 95% confidence interval [CI] = 1.34–3.99; women: OR = 1.99, 95% CI 1.23–3.21), low grip strength-to-BMI ratio (men: OR = 3.28, 95% CI 1.92–5.59; women: OR = 2.54, 95% CI 1.10–5.83) and low ALM-to-BMI ratio (men: OR = 1.58, 95% CI 1.12–2.25; women: OR = 1.81, 95% CI 1.14–2.87), but not low ALM, were associated with increased likelihood for incident mobility impairment. Weakness increased likelihood of mobility impairment regardless of low lean mass. Mortality risk patterns were inconsistent. Conclusions. These findings support our cut-points for low grip strength and low ALM-to-BMI ratio as candidate criteria for clinically relevant weakness and low lean mass. Further validation in other populations and for alternate relevant outcomes is needed.

Grip Strength Cutpoints for the Identification of Clinically Relevant Weakness

Background. Weakness is common and contributes to disability, but no consensus exists regarding a strength cutpoint to identify persons at high risk. This analysis, conducted as part of the Foundation for the National Institutes of Health Sarcopenia Project, sought to identify cutpoints that distinguish weakness associated with mobility impairment, defined as gait speed less than 0.8 m/s. Methods. In pooled cross-sectional data (9,897 men and 10,950 women), Classification and Regression Tree analysis was used to derive cutpoints for grip strength associated with mobility impairment. Results. In men, a grip strength of 26–32 kg was classified as “intermediate” and less than 26 kg as “weak”; 11% of men were intermediate and 5% were weak. Compared with men with normal strength, odds ratios for mobility impairment were 3.63 (95% CI: 3.01–4.38) and 7.62 (95% CI 6.13–9.49), respectively. In women, a grip strength of 16–20 kg was classified as “intermediate” and less than 16 kg as “weak”; 25% of women were intermediate and 18% were weak. Compared with women with normal strength, odds ratios for mobility impairment were 2.44 (95% CI 2.20–2.71) and 4.42 (95% CI 3.94–4.97), respectively. Weakness based on these cutpoints was associated with mobility impairment across subgroups based on age, body mass index, height, and disease status. Notably, in women, grip strength divided by body mass index provided better fit relative to grip strength alone, but fit was not sufficiently improved to merit different measures by gender and use of a more complex measure. Conclusions. Cutpoints for weakness derived from this large, diverse sample of older adults may be useful to identify populations who may benefit from interventions to improve muscle strength and function.

Socioeconomic status and C-reactive protein levels in the US population: NHANES IV

C-reactive protein (CRP), a marker of inflammation, has been identified as a risk factor for cardiovascular disease and mortality. Using data on adults aged 20 and over from the fourth National Health and Nutrition Examination Survey, a nationally representative cross-sectional survey, we examined the association between socioeconomic status and CRP in US adults (N=7634). Socioeconomic variation in CRP occurred only at very high levels of CRP (>10.0 mg/L). There was no significant difference in the prevalence of moderate (1.1-3.0 mg/L) or high values of CRP (3.1-10.0mg/L) by socioeconomic status; however, among those with family income at or below the poverty level, 15.7% had very high levels of CRP (greater than 10.0 mg/L), compared to only 9.1% of those in families above the poverty level. Logistic regression results indicate that acute illness, chronic conditions, and differential health behaviors account for about two-thirds of this association. African Americans, Hispanics, and women were more likely to have high levels of CRP. Obesity was the largest risk factor for every level of CRP above normal. Results suggest that differences in very high CRP may be due to factors beyond acute illness and may also reflect chronic health, behavioral and disease processes associated with low socioeconomic status.

The effect of obesity combined with low muscle strength on decline in mobility in older persons: results from the InCHIANTI Study

Objective:Both obesity and muscle impairment are increasingly prevalent among older persons and negatively affect health and physical functioning. However, the combined effect of coexisting obesity and muscle impairment on physical function decline has been little studied. We examined whether obese persons with low muscle strength experience significantly greater declines in walking speed and mobility than persons with only obesity or low muscle strength.Design:Community-dwelling adults aged ⩾65 years (n=930) living in the Chianti geographic area (Tuscany, Italy) were followed for 6 years in the population-based InCHIANTI study.Measurements:On the basis of baseline measurements (1998–2000), obesity was defined as body mass index (BMI) ⩾30 kg/m2 and low muscle strength as lowest sex-specific tertile of knee extensor strength. Walking speed and self-reported mobility disability (ability to walk 400 m or climb one flight of stairs) were assessed at baseline and at 3- and 6-year follow-up.Results:At baseline, obese persons with low muscle strength had significantly lower walking speed compared with all other groups (P⩽0.05). In longitudinal analyses, obese participants with low muscle strength had steeper decline in walking speed and high risk of developing new mobility disability over the 6-year follow-up compared with those without obesity or low muscle strength. After the age of 80, the differences between groups were substantially attenuated. The differences seen in walking speed across combination of low muscle strength and obesity groups were partly explained by 6-year changes in muscle strength, BMI and waist circumference.Conclusions:Obesity combined with low muscle strength increases the risk of decline in walking speed and developing mobility disability, especially among persons <80 years old.

Body fat distribution and inflammation among obese older adults with and without metabolic syndrome.

The protective mechanisms by which some obese individuals escape the detrimental metabolic consequences of obesity are not understood. This study examined differences in body fat distribution and adipocytokines in obese older persons with and without metabolic syndrome. Additionally, we examined whether adipocytokines mediate the association between body fat distribution and metabolic syndrome. Data were from 729 obese men and women (BMI ≥30 kg/m2), aged 70–79 participating in the Health, Aging and Body Composition (Health ABC) study. Thirty‐one percent of these obese men and women did not have metabolic syndrome. Obese persons with metabolic syndrome had significantly more abdominal visceral fat (men: P = 0.04; women: P < 0.01) and less thigh subcutaneous fat (men: P = 0.09; women: P < 0.01) than those without metabolic syndrome. Additionally, those with metabolic syndrome had significantly higher levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and plasminogen activator inhibitor‐1 (PAI‐1) than individuals without metabolic syndrome. Per standard deviation higher in visceral fat, the likelihood of metabolic syndrome significantly increased in women (odds ratio (OR): 2.16, 95% confidence interval (CI): 1.59–2.94). In contrast, the likelihood of metabolic syndrome decreased in both men (OR: 0.56, 95% CI: 0.39–0.80) and women (OR: 0.49, 95% CI: 0.34–0.69) with each standard deviation higher in thigh subcutaneous fat. These associations were partly mediated by adipocytokines; the association between thigh subcutaneous fat and metabolic syndrome was no longer significant in men. In summary, metabolically healthy obese older persons had a more favorable fat distribution, characterized by lower visceral fat and greater thigh subcutaneous fat and a more favorable inflammatory profile compared to their metabolically unhealthy obese counterparts.

Cutpoints for Low Appendicular Lean Mass That Identify Older Adults With Clinically Significant Weakness

Background. Low lean mass is potentially clinically important in older persons, but criteria have not been empirically validated. As part of the FNIH (Foundation for the National Institutes of Health) Sarcopenia Project, this analysis sought to identify cutpoints in lean mass by dual-energy x-ray absorptiometry that discriminate the presence or absence of weakness (defined in a previous report in the series as grip strength <26kg in men and <16kg in women). Methods. In pooled cross-sectional data stratified by sex (7,582 men and 3,688 women), classification and regression tree (CART) analysis was used to derive cutpoints for appendicular lean body mass (ALM) that best discriminated the presence or absence of weakness. Mixed-effects logistic regression was used to quantify the strength of the association between lean mass category and weakness. Results. In primary analyses, CART models identified cutpoints for low lean mass (ALM <19.75kg in men and <15.02kg in women). Sensitivity analyses using ALM divided by body mass index (BMI: ALMBMI) identified a secondary definition (ALMBMI <0.789 in men and ALMBMI <0.512 in women). As expected, after accounting for study and age, low lean mass (compared with higher lean mass) was associated with weakness by both the primary (men, odds ratio [OR]: 6.9 [95% CI: 5.4, 8.9]; women, OR: 3.6 [95% CI: 2.9, 4.3]) and secondary definitions (men, OR: 4.3 [95% CI: 3.4, 5.5]; women, OR: 2.2 [95% CI: 1.8, 2.8]). Conclusions. ALM cutpoints derived from a large, diverse sample of older adults identified lean mass thresholds below which older adults had a higher likelihood of weakness.

Creating Elder-Friendly Communities: Preparations for an Aging Society

Summary Because many communities where older people live were not designed for their needs, older residents may require support to remain in the least restrictive environment. ‘Age-prepared communities’ utilize community planning and advocacy to foster aging in place. ‘Elder-friendly communities’ are places that actively involve, value, and support older adults, both active and frail, with infrastructure and services that effectively accommodate their changing needs. This paper presents an analysis of the literature and results of a Delphi study identifying the most important characteristics of an elder-friendly community: accessible and affordable transportation, housing, health care, safety, and community involvement opportunities. We also highlight innovative programs and identify how social workers can be instrumental in developing elder-friendly communities.