Performance-based physical functioning in African-American and Caucasian women at midlife: considering body composition, quadriceps strength, and knee osteoarthritis

Race and ethnic disparities arthroplasty trends and hotspots: Bibliometric analysis

Introduction

Despite continual advancements in total joint arthroplasty and perioperative optimization, there remains national variability in outcomes. These outcome variabilities have been in part attributed to racial and ethnic disparities in healthcare quality and access to care. This study aims to identify arthroplasty racial and ethnic disparities research and to predict future hotspots.

Methods

Ethnic and racial disparities articles between 1992 and 2022 were queried from the Web of Science Core Collection of Clarivate Analytics. Bibliometric indicators in excel format were extracted and subsequently imported for further analysis. Bibliometrix and VOSviewer analyzed current and previous research.

Results

Database search yielded 234 total articles assessing racial and ethnic disparities between 1992 and 2022. Twenty-six countries published manuscripts with the United States producing the majority of publications. The Veterans Health Administration and University of Pittsburgh were the most relevant institutions. Ibrahim SA was the most relevant and influential author within this field. Visuals of thematic map and co-occurrences identified the basic, motor, and niche themes within the literature.

Conclusions

Racial and ethnic disparity within arthroplasty literature demonstrate growing traction with global contributions. United States authors and institutions are the largest contributors within this field. This bibliometric analysis identified previous, current, and future trends for prediction of future hotspots.

Environmental and sociocultural factors are associated with pain-related brain structure among diverse individuals with chronic musculoskeletal pain: intersectional considerations

Chronic musculoskeletal pain including knee osteoarthritis (OA) is a leading cause of disability worldwide. Previous research indicates ethnic-race groups differ in the pain and functional limitations experienced with knee OA. However, when socioenvironmental factors are included in analyses, group differences in pain and function wane. Pain-related brain structures are another area where ethnic-race group differences have been observed. Environmental and sociocultural factors e.g., income, education, experiences of discrimination, and social support influence brain structures. We investigate if environmental and sociocultural factors reduce previously observed ethnic-race group differences in pain-related brain structures. Data were analyzed from 147 self-identified non-Hispanic black (NHB) and non-Hispanic white (NHW), middle and older aged adults with knee pain in the past month. Information collected included health and pain history, environmental and sociocultural resources, and brain imaging. The NHB adults were younger and reported lower income and education compared to their NHW peers. In hierarchical multiple regression models, sociocultural and environmental factors explained 6-37% of the variance in pain-related brain regions. Self-identified ethnicity-race provided an additional 4-13% of explanatory value in the amygdala, hippocampus, insula, bilateral primary somatosensory cortex, and thalamus. In the rostral/caudal anterior cingulate and dorsolateral prefrontal cortex, self-identified ethnicity-race was not a predictor after accounting for environmental, sociocultural, and demographic factors. Findings help to disentangle and identify some of the factors contributing to ethnic-race group disparities in pain-related brain structures. Numerous arrays of environmental and sociocultural factors remain to be investigated. Further, the differing sociodemographic representation of our NHB and NHW participants highlights the role for intersectional considerations in future research.

Pituitary crosstalk with bone, adipose tissue and brain

Traditional textbook physiology has ascribed unitary functions to hormones from the anterior and posterior pituitary gland, mainly in the regulation of effector hormone secretion from endocrine organs. However, the evolutionary biology of pituitary hormones and their receptors provides evidence for a broad range of functions in vertebrate physiology. Over the past decade, we and others have discovered that thyroid-stimulating hormone, follicle-stimulating hormone, adrenocorticotropic hormone, prolactin, oxytocin and arginine vasopressin act directly on somatic organs, including bone, adipose tissue and liver. New evidence also indicates that pituitary hormone receptors are expressed in brain regions, nuclei and subnuclei. These studies have prompted us to attribute the pathophysiology of certain human diseases, including osteoporosis, obesity and neurodegeneration, at least in part, to changes in pituitary hormone levels. This new information has identified actionable therapeutic targets for drug discovery.

Environmental and sociocultural factors are associated with pain-related brain structure among diverse individuals with chronic musculoskeletal pain

Chronic musculoskeletal pain is a leading cause of disability worldwide. Previous research indicates ethnic/race groups are disproportionately affected by chronic pain conditions. However, when considering socioenvironmental factors these disparities are no longer observed. Ethnic/race group differences have also been reported in pain-related brain structure. Given that environmental and sociocultural factors influence biology and health outcomes, this study aimed to investigate possible environmental and sociocultural contributions to structural differences in pain-related brain regions. A total of 147 non-Hispanic black and non-Hispanic white, middle and older aged adults with knee pain in the past month and a brain MRI are included in the analyses. Individuals also provided information specific to health and pain history and environmental and sociocultural resources. In hierarchical multiple regression models, sociocultural and environmental factors explained 6%-37% of the variance in thickness of pain-related brain regions, with seven of the eight brain regions being statistically significant. In the amygdala, hippocampus, insula, bilateral primary somatosensory cortex, and thalamus, ethnicity/race provided an additional 4%-13% of explanatory value. In the rostral/caudal anterior cingulate and dorsolateral prefrontal cortex, ethnicity/race was not a predictor after accounting for environmental, sociocultural, and other demographic measures. Findings inform health disparities research by elucidating the complexity of factors contributing to previously reported ethnicity/race group differences.

Pre- and Early Peri-menopausal Physical Function and Risk of Cardiovascular Events: The Study of Women's Health Across the Nation

OBJECTIVES

To determine whether physical function (PF) before menopause is related to cardiovascular disease (CVD) risk.

METHODS

Participants were N = 2950 pre-/early peri-menopausal women (median age 46, (25th-75th percentile: 43-48 years). Physical function was assessed at baseline using the Physical Function subscale of the SF-36 and scores were trichotomized (no, some, or substantial limitations). Clinical CVD events were ascertained at annual/biennial clinical assessments through the 15th follow-up visit. Risk of CVD was determined with Cox proportional hazards models. Results: Women were followed for a median of 19.1 years, during which 220 women had a CVD event. In fully adjusted models, women with substantial limitations at baseline had higher CVD risk compared to women with no limitations (hazards ratio [HR] = 1.55, 95% confidence interval [CI]: 1.12-2.33). Discussion: Substantial PF limitations in pre- and early peri-menopausal women are associated with higher risk of clinical CVD events, consistent with literature in older adults.

Racial Differences in the Effect of HIV Status on Motor and Pulmonary Function and Mobility Disability in Older Adults

BACKGROUND

Older Black adults face a disproportionate burden of HIV prevalence, but less is known about racial disparities in age-related outcomes in HIV. We assessed the effect of HIV status and race on motor and pulmonary function, as well as how they contribute to mobility disability.

SETTING

Community-based study; Chicago, IL METHODS: Participants were 363 community-dwelling adults age ≥ 50 years, 48% living with HIV, and 68% Black. Participants with HIV were recruited from a specialty HIV clinic, and participants without HIV (comparable on key demographic, lifestyle, and behavioral characteristics) were recruited from the community. Measures included motor function summarized by 10 motor performance measures, pulmonary function summarized by 3 measures assessed using handheld spirometry, and self-reported mobility disability.

RESULTS

In fully adjusted linear models, HIV was associated with better motor (β = 9.35, p < 0.001) and pulmonary function (β = 16.34, p < 0.001). For pulmonary function, the effect of HIV status was moderated by race (interaction between Black race and HIV status: β =  - 11.66, p = 0.02), indicating that better pulmonary function among participants with HIV was less evident among Black participants. In fully adjusted models, odds of mobility disability did not differ by race, HIV status, or pulmonary function; better motor function was associated with lower odds of mobility disability (OR = 0.91 per 1-point higher, 95% CI 0.88-0.93).

CONCLUSION

Better motor and pulmonary function exhibited by participants with HIV could reflect access to medical care. Racial differences in lung function among participants with HIV indicate potential disparities in prevention or treatment of pulmonary disease or underlying risk factors.

FSH-blocking therapeutic for osteoporosis

Pharmacological and genetic studies over the past decade have established the follicle-stimulating hormone (FSH) as an actionable target for diseases affecting millions, namely osteoporosis, obesity, and Alzheimer's disease. Blocking FSH action prevents bone loss, fat gain, and neurodegeneration in mice. We recently developed a first-in-class, humanized, epitope-specific FSH-blocking antibody, MS-Hu6, with a KD of 7.52 nM. Using a Good Laboratory Practice (GLP)-compliant platform, we now report the efficacy of MS-Hu6 in preventing and treating osteoporosis in mice and parameters of acute safety in monkeys. Biodistribution studies using 89Zr-labeled, biotinylated or unconjugated MS-Hu6 in mice and monkeys showed localization to bone and bone marrow. The MS-Hu6 displayed a β phase t½ of 7.5 days (180 hr) in humanized Tg32 mice. We tested 217 variations of excipients using the protein thermal shift assay to generate a final formulation that rendered MS-Hu6 stable in solution upon freeze-thaw and at different temperatures, with minimal aggregation, and without self-, cross-, or hydrophobic interactions or appreciable binding to relevant human antigens. The MS-Hu6 showed the same level of "humanness" as human IgG1 in silico and was non-immunogenic in ELISpot assays for IL-2 and IFN-γ in human peripheral blood mononuclear cell cultures. We conclude that MS-Hu6 is efficacious, durable, and manufacturable, and is therefore poised for future human testing.

STEPS to Enhance Physical Activity After Hematopoietic Cell Transplantation for Multiple Myeloma

BACKGROUND

Finding effective ways to increase physical activity immediately following high-dose chemotherapy and autologous hematopoietic cell transplantation (HCT) for treatment of multiple myeloma (MM) is challenging.

OBJECTIVE

This pilot randomized clinical trial tested the acceptability, feasibility, and preliminary effects of a free-living physical activity intervention (STEPS) compared with usual care (UC) on physical activity, fatigue, muscle strength, functional ability, sleep, and quality of life following treatment for MM with HCT.

METHODS

Using a 2-group pretest/posttest design (N = 32), this study compared the 6-week STEPS intervention to UC. Data were collected using self-report questionnaires, functional performance tests, and wrist actigraphy before HCT and 7 weeks following hospital discharge.

RESULTS

The STEPS group achieved their physical activity goals on 53% of intervention days. The STEPS group experienced greater appetite loss, more diarrhea, and slept more than UC regardless of time point. Both groups reported improvements in mental fatigue, emotional functioning, pain, sleep disturbance, anger, anxiety, and depression but climbed stairs slower and had weaker hand grips after intervention. Both groups subjectively reported fewer sleep disturbances but objectively experienced more wakefulness after sleep onset and an increased number of awakenings postintervention.

CONCLUSIONS

The STEPS intervention is acceptable and feasible for people with MM treated with HCT. Both groups reported some improved symptoms but experienced some declines in physical performance postintervention.

IMPLICATIONS FOR PRACTICE

Nurses strive to optimize health and promote well-being. Helping people increase their physical activity after treatment for MM with HCT may improve symptoms, but additional studies are needed.

Association of Physical Activity and Physical Functioning Phenotypes With Fall Risk Among Women

Objective: Physical activity (PA) may slow aging-related declines in physical functioning (PF), but the relationship of PA and falls is not well understood. This study examined the association of PA and PF with falls. Methods: The Study of Women's Health Across the Nation participants (n = 1597; age: 65.1 years ± 2.7) reported PF and PA in 2012-2013 and falls in 2016-2017. Four phenotypes were identified: high PA-high PF, high PA-low PF, low PA-high PF, and low PA-low PF. Results: One-third (29.3%) reported ≥1 fall. Women with low PA-low PF (RR = 1.32; 95% CI: 1.06, 1.66) and with high PA-low PF (RR = 1.37; 95% CI: 1.07, 1.74) were more likely to fall than high PA-high PF. Over time, women with worsening PF had increased fall risk (RR = 1.43; 95% CI: 1.17, 1.74), but women who increased PA did not. Discussion: Poor PF increases the risk of falls, regardless of PA. However, increasing PA does not necessarily increase fall risk, reinforcing the importance of PA engagement.

The Roles of Body Composition and Specific Strength in the Relationship Between Race and Physical Performance in Older Adults

BACKGROUND

Socioeconomics may explain black-white differences in physical performance; few studies examine racial differences among socioeconomically similar groups. Performance is also affected by body composition and specific strength, which differ by race. We assessed whether racial differences in physical performance exist among older adults with high education and similar income and whether body composition and specific strength attenuate observed differences.

METHODS

Cross-sectional analysis of 536 men (18% black) and 576 women (28% black) aged more than 60 years from the Baltimore Longitudinal Study of Aging. Body composition was evaluated using dual-energy x-ray absorptiometry. Specific strength was assessed by quadricep peak torque divided by height-normalized thigh cross-sectional area and grip strength divided by body mass index-normalized appendicular lean mass. Physical performance was assessed using usual gait speed and fast 400 m walk time. Sex-stratified linear regression models, adjusted for age, height, education, and recent income, determined whether body composition or specific strength attenuated associations between race and physical performance.

RESULTS

Blacks were younger, with higher weight and appendicular lean mass. Black women had higher percent fat and specific strength. In both sexes, blacks had poorer physical performance after adjustment for socioeconomic factors. In women, neither body composition nor specific strength altered the association with gait speed. In men, neither body composition nor specific strength attenuated racial differences in either performance measure.

CONCLUSIONS

Poorer physical performance among black compared to white older adults persists among persons with high education and similar income and cannot generally be attributed to differences in body composition or specific strength.

The midlife transition and the risk of cardiovascular disease and cancer Part II: strategies to maximize quality of life and limit dysfunction and disease

Chronic dysfunction, disabilities, and complex diseases such as cardiovascular disease, diabetes mellitus type 2, osteoporosis and certain cancers, among other burdens, emerge and accelerate in midlife women. Previously in part l, we described the clinical and laboratory research findings that more readily explain and clarify the underlying pathogenetic mechanisms driving these clinical burdens, including new findings on how in particular visceral obesity and the emergence and acceleration of various components of metabolic syndrome-glucotoxicity and lipotoxicity-and a chronic systemic inflammatory state abetted by the loss of ovarian production of estradiol and the inevitable inroads of aging generate this spectrum of clinical problems. These research insights translate into opportunities for effective care strategies leading to prevention, amelioration, possible correction, and enhanced quality of life. To achieve these goals, updated detailed diagnostic, management, and therapeutic guidelines implemented by a reprogrammed and repurposed "menopause" office visit are described. A triage mechanism-when to refer to other specialists for further care-is emphasized. The previously polarized views of menopausal hormone therapy have narrowed significantly, leading to the construction of a more confident, unified, and wider clinical application. Accordingly, a menopausal hormone therapy program providing maximum benefit and minimum risk, accompanied by an algorithm for enhanced shared decision making, is included.

Percent body fat, but not lean mass, is associated with objectively measured physical function in middle-aged women

OBJECTIVES

The relationship between components of body composition and physical function is not well characterized among middle-aged women. This cross-sectional study examined the strength of the associations between lean mass and percent fat and physical function in middle-aged women.

STUDY DESIGN

Body composition, physical function and physical activity were objectively measured in 80 women (mean age 52.58 ± 6.10 years; range = 40-63 years).

MAIN OUTCOME MEASURES

Adiposity (%Fat) and lean mass were measured via dual-energy x-ray absorptiometry. Steps/day and minutes of low-, moderate- and vigorous-intensity physical activity were assessed via accelerometer. Physical function was measured via a seated transfer task, 30-second chair stand, a six-minute walk task, 8-foot timed up and go, and a lift and carry task.

RESULTS

When controlling for steps/day, measures of lean mass were related to performance on the seated transfer task (r = .25) and 30-second chair stand (-.26) (both p > 0.05), while %Fat was related to performance on the seated transfer task (r = .53), 8-foot timed up and go (r = .32), 30-second chair stand (r = -.35), and six-minute walk (r = -.48; all p ≤ 0.05). Linear regression analyses revealed: (1) age, steps/day, and %Fat were independently related to performance on the seated transfer task and 30-second chair stand (both p ≤ 0.05), (2) %Fat was associated with six-minute walk and 8-foot up-and-go performance (p ≤ 0.01); none of the variables included were associated with lift and carry.

CONCLUSIONS

Adiposity but not lean mass was associated with objectively measured physical function in middle-aged women. Interventions that focus on reducing body fat may be an effective method for improving functional performance among women in this age group.

Contribution of common chronic conditions to midlife physical function decline: The Study of Women's Health Across the Nation

Background

Chronic conditions are associated with worse physical function and commonly develop during midlife. We tested whether the presence of 8 chronic conditions, or the development of these conditions, is associated with declines in physical function among midlife women as they transition into early late life.

Methods

Participants (N = 2283) were from the Study of Women’s Health Across the Nation. Physical function was assessed at 8 visits starting at the study’s fourth clinic visit in 2000/2001 through follow-up visit 15 (2015/2017) using the Short Form-36 Physical Function subscale. Chronic conditions included diabetes, hypertension, osteoarthritis, osteoporosis, stroke, heart disease, cancer, and depressive symptoms. Repeated-measures Poisson regression modeled associations between 1) prevalent chronic conditions at analytic baseline (visit 4) and longitudinal physical function, and 2) change in physical function associated with developing a new condition. Models were adjusted with the total number of other chronic conditions at visit 4.

Results

In separate fully-adjusted longitudinal models, prevalent heart disease and osteoporosis were associated with 18% (IRR = 0.815, 95% confidence interval [CI]: 0.755–0.876) and 12% (IRR = 0.876, 95% CI: 0.825–0.927) worse initial physical function, respectively. Prevalent osteoarthritis was associated with approximately 6% (IRR = 0.936, 95% CI: 0.913–0.958) worse initial physical function, and a slight additional worsening over time (IRR = 0.995, 95% CI: 0.994–0.996). A 12% (IRR = 0.878, 95% CI: 0.813–0.950) decrease in physical function concurrent with stroke development was evident, as was accelerated decline in physical function concurrent with heart disease development (IRR = 0.991, 95% CI: 0.988–0.995).

Conclusions

Initial prevalent conditions related to the musculoskeletal system were associated with worse initial physical function, with some evidence of accelerated decline in physical function with osteoarthritis. Stroke and heart disease are less common than osteoarthritis in this age group, but the severe effects of these conditions on physical function shows the need for a greater focus on cardiovascular health during midlife. Women who develop chronic conditions during midlife may be at particular risk for poor physical function as they age, warranting disability prevention efforts focused on this population.

The relationship between urinary C-Telopeptide fragments of type II collagen, knee joint load, pain, and physical function in individuals with medial knee osteoarthritis

OBJECTIVE

Considering the osteoarthritis (OA) model that integrates the biological, mechanical, and structural components of the disease, the present study aimed to investigate the association between urinary C-Telopeptide fragments of type II collagen (uCTX-II), knee joint moments, pain, and physical function in individuals with medial knee OA.

METHODS

Twenty-five subjects radiographically diagnosed with knee OA were recruited. Participants were evaluated through three-dimensional gait analysis, uCTX-II level, the WOMAC pain and physical function scores, and the 40m walk test. The association between these variables was investigated using Pearson's product-moment correlation, followed by a hierarchical linear regression, controlled by OA severity and body mass index (BMI).

RESULTS

No relationship was found between uCTX-II level and knee moments. A significant correlation between uCTX-II level and pain, physical function, and the 40m walk test was found. The hierarchical linear regression controlling for OA severity and BMI showed that uCTX-II level explained 9% of the WOMAC pain score, 27% of the WOMAC physical function score, and 7% of the 40m walk test.

CONCLUSION

Greater uCTX-II level is associated with higher pain and reduced physical function and 40m walk test performance in individuals with medial knee OA.

Association of Race/Ethnicity With Hospital Discharge Disposition After Elective Total Knee Arthroplasty

IMPORTANCE

Total knee arthroplasty (TKA) is one of the most common elective procedures performed in adults with end-stage arthritis. Racial disparities in TKA outcomes have been described in the literature.

OBJECTIVES

To assess the association of race/ethnicity with discharge disposition and hospital readmission after elective primary TKA and to assess the association of nonhome discharge disposition with hospital readmission risk.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from the Pennsylvania Health Care Cost Containment Council Database, a large regional database that included demographic data from all discharges of patients who underwent elective primary TKA in 170 nongovernmental acute care hospitals in Pennsylvania from April 1, 2012, to September 30, 2015. Data analyses were conducted from September 29, 2017, to November 29, 2017.

EXPOSURES

Patient race/ethnicity and discharge disposition.

MAIN OUTCOMES AND MEASURES

Discharge disposition and 90-day hospital readmission.

RESULTS

Among 107 768 patients, 7287 (6.8%) were African American, 68 372 (63.4%) were women, 46 420 (43.1%) were younger than 65 years, and 60 636 (56.3%) were insured by Medicare. In multivariable logistic regression, among patients younger than 65 years, African American patients were more likely than white patients to be discharged to inpatient rehabilitation facility (IRF) (adjusted relative risk ratio [aRRR], 2.49 [95% CI, 1.42-4.36]; P = .001) or a skilled nursing facility (SNF) (aRRR, 3.91 [95% CI, 2.17-7.06]; P < .001) and had higher odds of 90-day hospital readmission (adjusted odds ratio [aOR], 1.30 [95% CI, 1.02-1.67]; P = .04). Compared with white patients 65 years or older, African American patients 65 years or older were more likely to be discharged to SNF (aRRR, 3.30 [95% CI, 1.81-6.02]; P < .001). In both age groups, discharge to an IRF (age <65 years: aOR, 3.62 [95% CI, 2.33-5.64]; P < .001; age ≥65 years: aOR, 2.85 [95% CI, 2.25-3.61]; P < .001) or SNF (age <65 years: aOR, 1.91 [95% CI, 1.37-2.65]; P < .001; age ≥65 years: aOR, 1.55 [95% CI, 1.27-1.89]; P < .001) was associated with higher odds of 90-day readmission.

CONCLUSIONS AND RELEVANCE

This cohort study found that race/ethnicity was associated with higher odds of discharge to an IRF or SNF for postoperative care after primary TKA. Among patients younger than 65 years, African American patients were more likely than white patients to be readmitted to the hospital within 90 days. Discharge to an IRF or SNF for postoperative care and rehabilitation was also associated with a higher risk of readmission to an acute care hospital.

The menopause transition and women's health at midlife: a progress report from the Study of Women's Health Across the Nation (SWAN)

OBJECTIVE

Our initial understanding of the menopause transition (MT) has been framed by clinical samples of women seeking treatment rather than by population-based studies. The Study of Women's Health Across the Nation (SWAN) initiated in 1996 with an overall goal to define the MT, to characterize its biological and psychosocial antecedents and sequelae in an ethnically and racially diverse sample of midlife women.

METHODS

This review summarizes the central findings of SWAN to date that can inform women and their healthcare providers about the impact of the MT and midlife aging on overall health and well-being.

RESULTS

SWAN characterized changes in reproductive axis and menstrual cycle patterns that informed the development of the reproductive aging staging system Staging of Reproductive Aging Workshop+10; MT-related symptoms and mental health (vasomotor symptoms, sleep complaints, psychological symptoms, cognitive performance, and urogenital and sexual health); and physiological systems and functions (cardiovascular and cardiometabolic health, bone health, physical function performance) that are influenced by the MT. SWAN demonstrated substantial interrelations among these changes and significant racial/ethnic differences in the rate and magnitude of change in multiple health indictors in midlife women. The findings point to midlife as a critical stage for adopting healthy behavior and preventive strategies.

CONCLUSIONS

Over the past 23 years, SWAN has advanced our understanding of the impact of the MT and midlife aging on health and well-being in women. SWAN will be instrumental to determine whether MT-related changes during midlife are related to unfavorable health and well-being in early old age.

Pain Provocation and the Energy Cost of Walking: A Matched Comparison Study of Older Adults With and Without Chronic Low Back Pain With Radiculopathy

BACKGROUND AND PURPOSE

Chronic low back pain with radiculopathy (CLBPR) is common among older adults and can lead to walking difficulty. Energy cost of walking strongly predicts changes in walking speed, which is predictive of mortality in older adults. The purposes of this study were to examine (1) the impact of pain provocation on the energy cost of walking and (2) the relationship between pain intensity and change in energy cost of walking.

METHODS

Older adults (60-85 years) with (n = 20) and without (n = 20) CLBPR were matched on age, sex, and diabetes presence/absence. Energy cost of walking was measured with a portable metabolic gas analyzer, as participants walked for 20 minutes or less. Energy cost and pain measurements occurred during early and late stages of walking. Percent change in energy cost was calculated. Participants were grouped by their pain response during walking: increased pain (n = 13); consistent pain (n = 7); no pain, matched to individuals with increased pain (n = 13); and no pain, matched to individuals with consistent pain (n = 7). We examined the within-groups change in energy cost for all groups, as well as the relationship between late-stage pain intensity and percent change of energy cost for individuals whose pain increased.

RESULTS AND DISCUSSION

Within the increased pain group, energy cost of walking significantly increased from early to late stages (median change = 0.003 mL/kg/m, P = .006), and late-stage pain intensity explained 41.2% (p = 0.040) of the variance in percent change. Since pain appears to be linked to energy cost, effective pain management with walking may be an important factor in preventing mobility decline.

CONCLUSIONS

Among older adults with CLBPR, pain provocation drives increases in the energy cost of walking. Because high energy cost of walking is predictive of mobility decline, clinicians may focus on effective pain management strategies during walking, which may potentially decrease the risk of mobility decline.

Factors Influencing Longitudinal Stair Climb Performance from Midlife to Early Late Life: The Study of Women's Health Across the Nation Chicago and Michigan Sites

OBJECTIVES

To quantify the longitudinal change in stair climb performance (a measure indicative of both physical function and muscle power), determine whether physical activity is related to slower decline in performance, and to identify factors that modify the longitudinal change in performance among women from midlife to late life.

DESIGN

Longitudinal cohort study with up to 15 study visits.

SETTING

Two sites of the Study of Women's Health Across the Nation.

PARTICIPANTS

Black (n=411) and white (N=419) women followed from median age 47.0 (44.6-49.6) to 62.0 (55.8-65.3) years.

INTERVENTIONS

N/A.

MEASUREMENTS

Performance on a stair climb test (ascend/descend 4 steps, 3 cycles) was timed. Physical activity (PA) was assessed using the Kaiser Physical Activity Survey (KPAS; possible range 0-15 points). Sociodemographic and health factors were assessed via self-report. BMI was calculated with measured height and weight. Mixed-effects regression modeled longitudinal change in stair climb performance.

RESULTS

Average baseline stair climb time was 18.12 seconds (95% CI: 17.83-18.41), with 0.98% (95% CI: 0.84%-1.11%) annual slowing. In fully adjusted models, higher levels of PA were associated with faster stair climb times (2.09% faster per point higher, 95% CI: -2.87%- -1.30%), and black women had 5.22% (95% CI: 2.43%-8.01%) slower performance compared to white women. Smoking, financial strain, diabetes, osteoarthritis, fair/poor health, and stroke were associated with 3.36% (95% CI: 0.07%-6.65%), 7.56% (95% CI: 4.75%-10.37%), 8.40% (95% CI: 2.89%-13.92%), 8.46% (95% CI: 5.12%-11.79%), 9.16% (95% CI: 4.72%-13.60%), and 16.94% (95% CI: 5.37%-28.51%) slower performance, respectively. In separate models, higher BMI (per 1-unit), osteoarthritis, fair/poor health, and diabetes, were each associated with 0.06% (95% CI:0.04%-0.08%), 0.48% (95% CI:0.12%-0.84%), 0.81% (95% CI:0.35%-1.28%), and 0.84% (95% CI:0.22%-1.46%), additional slowing per year over time.

CONCLUSION

Significant declines in function were evident as women transitioned from midlife to early late life. Declines were amplified by indicators of poor health, emphasizing the importance of health in midlife for promoting healthy aging.

Racial-Ethnic Differences in Osteoarthritis Pain and Disability: A Meta-Analysis

Osteoarthritis (OA), a leading cause of disability and pain, affects 32.5 million Americans, producing tremendous economic burden. Although some findings suggest that racial/ethnic minorities experience increased OA pain severity, other studies have shown conflicting results. This meta-analysis examined differences in clinical pain severity between African Americans (AAs) and non-Hispanic whites with OA. Articles were initially identified between October 1 and 5, 2016, and updated May 30, 2018, using PubMed, Web of Science, PsycINFO, and the Cochrane Library Database. Eligibility included English-language peer-reviewed articles comparing clinical pain severity in adult black/AA and non-Hispanic white/Caucasian patients with OA. Nonduplicate article abstracts (N = 1,194) were screened by 4 reviewers, 224 articles underwent full-text review, and 61 articles reported effect sizes of pain severity stratified by race. Forest plots of the standard mean difference showed higher pain severity in AAs for studies using the Western Ontario and McMasters Universities Osteoarthritis Index (0.57; 95% confidence interval [CI], 0.54-0.61) and non-Western Ontario and McMasters Universities Osteoarthritis Index studies (0.35, 95% CI, 0.23-0.47). AAs also showed higher self-reported disability (0.38, 95% CI, 0.22-0.54) and poorer performance testing (-0.58, 95% CI, -0.72 to -0.44). Clinical pain severity and disability in OA is higher among AAs and future studies should explore the reasons for these differences to improve pain management. PERSPECTIVE: This meta-analysis shows that differences exist in clinical pain severity, functional limitations, and poor performance between AAs and non-Hispanic whites with OA. This research may lead to a better understanding of racial/ethnic differences in OA-related pain.

Physical Activity and Physical Function: Moving and Aging

Evidence supports that the physical disablement process starts earlier than previously thought, in midlife when women still have many years to live. Physical activity participation and interventions have been successful in preventing disability in older adults and may be promising for maintaining function at younger ages. Changing the conversation to more relevant topics in midlife, like positive changes in body composition, sleep, and improved mood, may move the dial on participation, as midlife women do not meet guidelines for physical activity. Exploring the role of reproductive aging beyond chronologic aging may provide gender-specific insights on both disablement and participation.

Evaluation of the Measurement Properties of Four Performance Outcome Measures in Patients with Elective Hip Replacements, Elective Knee Replacements, or Hip Fractures

OBJECTIVES

To evaluate the measurement properties of four performance outcome (PerfO) measures (timed up and go, four-step stair climb, long stair climb, and repeated chair stand) in three patient populations(elective total hip replacement [eTHR], elective total knee replacement [eTKR], and hip fracture [HF]).

METHODS

A cross-sectional and longitudinal design was used to assess the PerfO measurement properties using the US Food and Drug Administration guidance for industry around patient-reported outcome measures to support labeling claims. Patient-reported outcome measures and patient- and clinician-reported global concept items were completed along with four PerfO measures at visit 1 and two follow-up visits. Measurement properties assessed included reliability, construct validity, ability to detect change, and estimates of meaningful change.

RESULTS

A total of 280 patients (100 eTHR, 105 eTKR, and 75 HF) were recruited, with most (n = 276) providing data at visit 1. Most of the patients were female (64%) and retired (64%), and had at least one comorbidity (91%). Inter-rater and test-retest reliability ranged from good to excellent (0.73 ≤ intraclass correlation coefficient ≤ 0.95) for each PerfO measure. Known-groups validity was demonstrated for all PerfO measures, with those reporting less pain better physical functioning and those who did not use an assistive device having quicker mean completion times. Construct validity and ability to detect change were demonstrated and estimates of meaningful change derived.

CONCLUSIONS

This study found the measurement properties of four PerfO measures in samples of patients with eTHR, eTKR, and HF to be supported for consideration of future use, and provided estimates for interpretation of change.

Pain Energy Model of Mobility Limitation in the Older Adult

Background

Chronic pain is prevalent, costly, and disabling among older adults. Although mobility decline is inevitable with aging, it is clear, from current evidence, that older adults with chronic pain experience a greater rate of functional mobility decline than their pain-free peers. Past studies suggest that pain expedites the age-related decline in functional mobility; however, the pathways through which pain affects mobility remain unclear. Gerontological experts hypothesize that the age-related decline in mobility may be driven by alterations in energy expenditure; these concepts are outlined in a model known as the Energetic Pathway of Mobility Loss. Pain may play a critical role in this process through a pathway of energetic inefficiency, physical inactivity, and decreased capacity.

Purpose

The purposes of this article are to 1) summarize the current literature that supports the Energetic Pathway of Mobility Loss model and 2) propose a new framework, known as the Pain Energy Model, to clarify how the disablement process may be amplified among older adults with painful conditions.

Conclusion

This new framework is designed to generate new clinical research and to suggest new clinical implications for older adults with painful conditions by identifying key steps and potential treatment targets in the pathway to functional mobility decline.

Steps to Enhance Early Recovery After Hematopoietic Stem Cell Transplantation: Lessons Learned From a Physical Activity Feasibility Study

AIMS

This pilot study tested and refined a free-living physical activity intervention. The investigators evaluated the acceptability and feasibility of the intervention after hematopoietic stem cell transplantation and determined preliminary effects on physical activity, fatigue, muscle strength, functional ability, and quality of life.

DESIGN

This pilot study used a 1-group, pretest-posttest design.

METHODS

The free-living physical activity intervention consisted of an education component and 6 weeks of gradually increasing physical activity after discharge from the hospital. The intervention was designed to increase steps by 10% weekly. Subjects were assessed before transplantation and during the seventh week after discharge from the hospital after completing the intervention. Pretest-posttest scores were analyzed with paired t tests.

RESULTS

Subject wore the physical activity tracker for an average of 38 of 42 days and met their physical activity goals 57% of the time. Subjects reported significantly less physical fatigue after the free-living physical activity intervention compared with baseline (P = .05). Improvements in quality of life approached significance (P = .06).

CONCLUSION

The findings demonstrate that the free-living physical activity intervention implemented during the very early recovery period after transplantation is feasible and acceptable. The intervention potentially reduces fatigue and improves quality of life. The positive results must be interpreted cautiously given the pilot nature of the study. The evidence supports continued investigation.

Strength Training to Enhance Early Recovery after Hematopoietic Stem Cell Transplantation

Intensive cancer treatment followed by hematopoietic stem cell transplantation (HCT) results in moderate to severe fatigue and physical inactivity, leading to diminished functional ability. The purpose of this study was to determine the efficacy of an exercise intervention, strength training to enhance early recovery (STEER), on physical activity, fatigue, muscle strength, functional ability, and quality of life after HCT. This single-blind, randomized clinical trial compared strength training (n = 33) to usual care plus attention control with health education (UC + AC with HE) (n = 34). Subjects were stratified by type of transplantation and age. STEER consisted of a comprehensive program of progressive resistance introduced during hospitalization and continued for 6 weeks after hospital discharge. Fatigue, physical activity, muscle strength, functional ability, and quality of life were assessed before HCT hospital admission and after intervention completion. Data were analyzed using split-plot analysis of variance. Significant time × group interactions effects were noted for fatigue (P = .04). The STEER group reported improvement in fatigue from baseline to after intervention whereas the UC + AC with HE group reported worsened fatigue from baseline to after intervention. Time (P < .001) and group effects (P = .05) were observed for physical activity. Physical activity declined from baseline to 6 weeks after hospitalization. The STEER group was more physically active. Functional ability tests (timed stair climb and timed up and go) resulted in a significant interaction effect (P = .03 and P = .05, respectively). Subjects in the UC + AC with HE group were significantly slower on both tests baseline to after intervention, whereas the STEER group's time remained stable. The STEER group completed both tests faster than the UC + AC with HE group after intervention. Study findings support the use of STEER after intensive cancer treatment and HCT. Strength training demonstrated positive effects on fatigue, physical activity, muscle strength, and functional ability. The exact recovery patterns between groups and over time varied; the STEER group either improved or maintained their status from baseline to after intervention (6 weeks after hospital discharge) whereas the health education group generally declined over time or did not change.

Body mass index, falls, and injurious falls among U.S. adults: Findings from the 2014 Behavioral Risk Factor Surveillance System

Falls are an important health concern because they are associated with loss of independence and disability, particularly among women. We determined the age- and sex-specific prevalence of injurious falls among adults in the United States and examined the impact of obesity on fall risk. Self-reported falls, injurious falls, and health histories were obtained from 280,035 adults aged 45-79years in the 2014 Behavioral Risk Factor Surveillance System. Body mass index was categorized as underweight (<18.5kg/m²), normal weight (18.5-24.9kg/m²), overweight 25-29.9kg/m²), class I obesity (30.0-34.9kg/m²), or class II/III obesity (≥35.0kg/m²) based on self-reported height and weight. Data were analyzed using weighted age- and sex-specific prevalence rates and Poisson regression. Overall, 11.0% reported ≥1 injurious fall in the previous 12months. Mid-life women 55-59years reported the highest prevalence of injurious falls (15.4%). Among mid-life women, overweight was associated with injurious falls (RR=1.17; 95% CI: 1.08, 1.28), but overweight was not associated with falling among other age-sex groups. Class II/III obesity was associated with injurious falls among all age-sex groups. After considering the mediators like health conditions (depression, cardiovascular disease, diabetes, arthritis) and behaviors (physical activity, sleep), the association of class II/III obesity and injurious fall risk persisted only among mid-life women (RR=1.23; 95% CI: 1.12, 1.36). Not only are mid-life women at high risk for falls, but the class II/III obesity is a risk factor for injurious falls. Targeting mid-life women for fall and injury prevention is an important aim for practitioners, particularly given unique correlates of falling for this group.

Factors associated with disability among middle-aged and older African American women with osteoarthritis

BACKGROUND

Middle-aged and older African American women experience disproportionate rates of functional limitations and disability from osteoarthritis (OA) compared to other racial ethnic groups; however, little is known about what factors contribute to this disparity within African American women.

OBJECTIVE

To examine factors associated with physical function and disability among African American women ages 50-80 with OA using the disablement process model.

METHODS

This descriptive study included 120 African American women with OA from the Southwestern region of the United States. Regression techniques were used to model the correlates of physical function and disability and to test a mediation model.

RESULTS

BMI and pain severity were significantly related to functional limitations. Depressive symptoms mediated the relationship between racial discrimination and disability.

CONCLUSION

Biological, intra-individual, and extra-individual factors are related to disablement outcomes in this sample of African American women, which is consistent with theory suggesting the need for treatment coupled with environmental modifications. This study can inform the development of future bio-behavioral interventions.

Gait Speeds Associated with Anxiety Responses to Pain in Osteoarthritis Patients

OBJECTIVE

Patients with lower limbs osteoarthritis (OA) had slower walking speeds than healthy. Gait speed, which is associated with leg muscle strength, is a consistent predictor of health and functional status. The effects of pain and pain-related psychological constructs for gait speeds have been uncertain. Therefore, we investigated whether gait speed in patients with OA of lower limbs is associated with pain-related psychological constructs using a performance-based measure.

METHODS

The study group comprised 59 patients with advanced knee or hip OA. Gait speeds were measured at comfortable and maximum levels during 10-m walks. Covariates included 1) pain intensity measured with a visual analogue scale (VAS), 2) psychological constructs measured with a short-version pain anxiety symptoms scale (PASS-20) and the hospital anxiety and depression scale (HADS), and 3) bilateral knee extensor and hip abductor muscle strength. Each variable was subjected to multivariate analysis with gait speed.

RESULTS

Single regression analysis showed that gait speeds were significantly correlated with VAS and PASS-20 scores, and muscle strength, not with HADS. Multiple regression analysis showed that PASS-20 score was significant correlating factor for gait speeds.

CONCLUSIONS

Anxiety-related responses to pain were significant correlating factor for gait speeds, in patients with OA of lower limbs.

Higher Leptin and Adiponectin Concentrations Predict Poorer Performance-based Physical Functioning in Midlife Women: the Michigan Study of Women's Health Across the Nation

BACKGROUND

Excess fat mass is a greater contributor to functional limitations than is reduced lean mass or the presence of obesity-related conditions. The impact of fat mass on physical functioning may be due to adipokines, adipose-derived proteins that have pro- or anti-inflammatory properties.

METHODS

Serum samples from 1996 to 2003 that were assayed for leptin, adiponectin, and resistin were provided by 511 participants from the Michigan site of the Study of Women's Health Across the Nation. Physical functioning performance was assessed annually during study visits from 1996 to 2003.

RESULTS

Among this population of Black and White women (mean baseline age = 45.6 years, SD = 2.7 years), all of whom were premenopausal at baseline, higher baseline leptin concentrations predicted longer stair climb, sit-to-rise, and 2-pound lift times and shorter forward reach distance (all p < .01). This relationship persisted after adjustment for age, BMI, percent skeletal muscle mass, race/ethnicity, economic strain, bodily pain, diabetes, knee osteoarthritis, and C-reactive protein. Baseline total adiponectin concentrations did not predict any mobility measures but did predict quadriceps strength; a 1 µg/mL higher adiponectin concentration was associated with 0.64 Nm lower quadriceps strength (p = .02). Resistin was not associated with any of the physical functioning performance measures. Change in the adipokines was not associated with physical functioning.

CONCLUSION

In this population of middle-aged women, higher baseline leptin concentrations predicted poorer mobility-based functioning, whereas higher adiponectin concentrations predicted reduced quadriceps strength. These findings suggest that the relationship between the adipokines and physical functioning performance is independent of other known correlates of poor functioning.

Knee Extensor Power Relates to Mobility Performance in People With Knee Osteoarthritis: Cross-Sectional Analysis

BACKGROUND

Quadriceps femoris muscle strengthening is a common rehabilitation exercise for knee osteoarthritis (OA). More information is needed to determine whether targeting muscle power is a useful adjunct to strengthening for people with knee OA.

OBJECTIVE

The purpose of this study was to identify the predictive ability of knee extensor strength and knee extensor power in the performance of physical tasks in adults with knee OA.

DESIGN

This study used a cross-sectional design.

METHODS

Fifty-five participants with clinical knee OA were included (43 women; mean [SD] age=60.9 [6.9] years). Dependent variables were: timed stair ascent, timed stair descent, and the Six-Minute Walk Test (6MWT). Independent variables were: peak knee extensor strength and mean peak knee extensor power. Covariates were: age, body mass index, and self-efficacy. Multiple regression analyses were run for each dependent variable with just covariates, then a second model including strength, and then a third model including power. The R(2) values were compared between models.

RESULTS

Power explained greater variance than strength in all models. Over and above the covariates, power explained an additional 6% of the variance in the 6MWT, increasing the R(2) value from .33 to .39; 8% in the stair ascent test, increasing the R(2) value from .52 to .60; and 3% in the stair descent test, increasing the R(2) value from .44 to .47.

LIMITATIONS

The sample demonstrated very good mobility and muscle function scores and may not be indicative of those with severe knee OA.

CONCLUSIONS

In adults with knee OA, knee extensor power was a stronger determinant of walking and stair performance when compared with knee extensor strength. Clinicians should consider these results when advising patients on exercise to maintain or improve mobility.

Race Differences: Use of Walking Speed to Identify Community-Dwelling Women at Risk for Poor Health Outcomes--Osteoarthritis Initiative Study

BACKGROUND

Onset of disability, risk for future falls, frailty, functional decline, and mortality are strongly associated with a walking speed of less than 1.0 m/s.

OBJECTIVE

The study objective was to determine whether there were differences in slow walking speed (<1.0 m/s) between community-dwelling African American and white American adult women with osteoarthritis symptoms. An additional aim was to examine whether racial differences in walking speed can be attributed to age, obesity, socioeconomic factors, disease severity, or comorbidities.

DESIGN

A cross-sectional design was used.

METHODS

Community-dwelling adults were recruited from Baltimore, Maryland; Columbus, Ohio; Pittsburgh, Pennsylvania; and Pawtucket, Rhode Island. Participants were 2,648 women (23% African American) who were 45 to 79 years of age and had a self-selected baseline walking speed of 20 m/s in the Osteoarthritis Initiative Study. Mixed-effects logistic regression models were used to examine racial differences in walking speed (<1.0 m/s versus ≥1.0 m/s), with adjustments for demographic factors, socioeconomic factors, disease severity, and comorbidities.

RESULTS

Walking speed was significantly slower for African American women than for white American women (mean walking speed=1.19 and 1.33 m/s, respectively). The prevalence of a walking speed of less than 1.0 m/s in this cohort of middle-aged women was 9%; about 50% of the women with a walking speed of less than 1.0 m/s were younger than 65 years. Women with a walking speed of less than 1.0 m/s had lower values for socioeconomic factors, higher values for disease severity, and higher prevalences of obesity and comorbidities than those with a walking speed of ≥1.0 m/s. After controlling for these covariates, it was found that African American women were 3 times (odds ratio=2.9; 95% confidence interval=2.0, 4.1) more likely to have a walking speed of less than 1.0 m/s than white American women.

LIMITATIONS

The study design made it impossible to know whether a walking speed of less than 1.0 m/s in women who were 45 years of age or older was a predictor of future poor health outcomes.

CONCLUSIONS

In this study, race was independently associated with a walking speed of less than 1.0 m/s in community-dwelling women who had or were at risk for osteoarthritis, with African American women having 3 times the risk for slow walking as white American women. This finding suggests that middle-aged African American women have an increased risk for poor health outcomes. Further longitudinal evaluations are needed to confirm the long-term health outcomes in a middle-aged population and to establish walking speed as a useful tool for identifying middle-aged women at high risk for poor health outcomes.

Racial and ethnic differences in older adults with knee osteoarthritis

OBJECTIVE

Knee osteoarthritis (OA) contributes significantly to disability in older individuals, and racial/ethnic minorities are disproportionately affected. The present study aimed to characterize differences in clinical and experimental pain, including pain inhibition, among older African American (AA) and non-Hispanic white (NHW) subjects with knee OA.

METHODS

AA and NHW subjects with knee OA (n = 267) completed clinical and functional pain assessments, including quantitative sensory testing (QST). We hypothesized that, when compared to NHW subjects, AA subjects would display 1) lower pain tolerance and higher ratings of heat-, mechanical-, and cold-induced pain, 2) greater temporal summation of pain, 3) reduced pain inhibition, and 4) greater clinical pain and poorer function. In addition, we hypothesized that the findings from QST would significantly predict the severity of clinical pain within each race/ethnicity.

RESULTS

AA subjects with knee OA displayed increased pain sensitivity, greater temporal summation, and reduced pain inhibition when compared to NHW subjects with knee OA. Moreover, AA subjects reported greater clinical pain and poorer function. Racial/ethnic differences in clinical pain became nonsignificant when the analyses were controlled for education and annual income, whereas differences in QST findings remained highly significant. Although the extent of pain inhibition predicted the severity of clinical pain in both groups, different QST measures were additionally predictive of clinical pain within each group.

CONCLUSION

The results of this study establish that there are racial/ethnic differences in experimental and clinical pain and function in older individuals with knee OA. Our findings indicating that different QST measures were associated with clinical pain within the 2 racial/ethnic groups, whereas reduced pain inhibition was important in all participants, warrant further study in order to elucidate the common and group-specific pathophysiologic mechanisms contributing to clinical pain in OA.

Prevalence and correlates of disability in a late middle-aged population of women

OBJECTIVE

This study estimates the prevalence of disability among late middle-aged women and identifies important correlates of disability among this population.

METHOD

Disability was assessed among 376 participants of the Michigan Study of Women's Health Across the Nation cohort at the 2011 follow-up using the World Health Organization Disability Assessment Schedule. Demographic and health measures were related to disability status using logistic regression models (none or mild vs. moderate, severe, or extreme disability).

RESULTS

Nearly 25% of women reported moderate to extreme global disability. African American race/ethnicity, economic strain, peripheral neuropathy, and depressive symptomatology were associated with global disability. Obesity, knee osteoarthritis, and hypertension were only associated with disability for the mobility domain (getting around).

DISCUSSION

The prevalence of disability is relatively high among this population of late middle-aged women. Efforts to prevent or forestall disability should be extended to include middle-aged populations as they may be most amenable to intervention.

Performance-based physical functioning and peripheral neuropathy in a population-based cohort of women at midlife

Peripheral neuropathy is underappreciated as a potential cause of functional limitations. In the present article, we assessed the cross-sectional association between peripheral neuropathy and physical functioning and how the longitudinal association between age and functioning differed by neuropathy status. Physical functioning was measured in 1996-2008 using timed performances on stair-climb, walking, sit-to-stand, and balance tests at the Michigan site of the Study of Women's Health Across the Nation, a population-based cohort study of women at midlife (n = 396). Peripheral neuropathy was measured in 2008 and defined as having an abnormal monofilament test result or 4 or more symptoms. We used linear mixed models to determine whether trajectories of physical functioning differed by prevalent neuropathy status. Overall, 27.8% of the women had neuropathy. Stair-climb time differed by neuropathy status (P = 0.04), and for every 1-year increase in age, women with neuropathy had a 1.82% (95% confidence interval: 1.42, 2.21) increase compared with a 0.95% (95% confidence interval: 0.71, 1.20) increase for women without neuropathy. Sit-to-stand time differed by neuropathy status (P = 0.01), but the rate of change did not differ. No differences between neuropathy groups were observed for the walk test. For some performance-based tasks, poor functioning was maintained or exacerbated for women who had prevalent neuropathy. Peripheral neuropathy may play a role in physical functioning limitations and future disability.

Is symptomatic knee osteoarthritis a risk factor for a trajectory of fast decline in gait speed? Results from a longitudinal cohort study

OBJECTIVE

Gait speed is an important marker of health in adults and slows with aging. While knee osteoarthritis (OA) can result in difficulty walking, it is not known if radiographic knee OA (ROA) and/or knee pain are associated with a fast decline trajectory of gait speed over time.

METHODS

Gait speed trajectories were constructed using a multinomial modeling strategy from repeated 20-meter walk tests measured annually over 4 years among participants from the Osteoarthritis Initiative, a prospective cohort study of adults ages 45-79 years at baseline with or at high risk of knee OA. We grouped participants into 4 knee OA categories (having neither ROA nor knee pain, ROA only, knee pain only, or symptomatic knee OA [ROA and pain]) and examined their association with trajectories of gait speed using a multivariable polytomous regression model adjusting for age and other potential confounders.

RESULTS

Of the 4,179 participants (mean ± SD age 61.1 ± 9.1 years, 57.6% women, mean ± SD body mass index 28.5 ± 4.8 kg/m(2) ), 5% (n = 205) were in a fast decline trajectory, slowing at a rate of 2.75%/year. People with symptomatic knee OA had an almost 9-fold risk (odds ratio 8.9; 95% confidence interval [95% CI] 3.1, 25.5) of being in a fast decline trajectory compared with those with neither pain nor ROA. Participants with knee pain had 4.5 times the odds of a fast decline (95% CI 1.4, 14.6), and those with ROA only had a slight but non-statistically significant increased risk.

CONCLUSION

People with symptomatic knee OA have the highest risk of a fast decline trajectory of gait speed compared with people with ROA or pain alone.

Association between seated postural control and gait speed in knee osteoarthritis

The purpose of this study was to evaluate, in patients with knee osteoarthritis, whether seated postural control is a multivariate predictor of gait speed, after adjusting for the effects of conventional knee impairments. Sixty-seven patients with knee osteoarthritis awaiting total knee replacement participated. To measure seated postural control, patients sat on a balance board, and the centre-of-pressure (COP) measures calculated in the anterior-posterior (AP) and medio-lateral (ML) directions were standard deviation (SD) and mean frequency (MF). Isometric knee extensor strength was measured using an isokinetic dynamometer; knee flexion range-of-motion, an extendable goniometer; and knee pain intensity, a numeric pain rating scale. Fast-pace gait speed was assessed by the 10-m walk test and a poor gait speed was defined at a cutoff value of 1.0m/s. At the univariate level, the seated COP measures, with the exception of AP-MF, discriminated between patients with and without poor gait speed; however, only ML-MF retained its predictive value in multivariable analyses adjusted for demographic, anthropometric, and knee impairment measures. These findings suggest that seated postural control may be an important correlate of physical function in patients with knee OA and that greater emphasis in the assessment of trunk control may be warranted in this population.

Sex dimorphism in the association of cardiometabolic characteristics and osteophytes-defined radiographic knee osteoarthritis among obese and non-obese adults: NHANES III

OBJECTIVE

To examine the relationship of knee osteoarthritis (OA) with cardiovascular and metabolic risk factors by obesity status and gender.

METHODS

Data from 1,066 National Health and Nutrition Examination Survey III participants (≥60 years of age) was used to examine relationships of osteophytes-defined radiographic knee OA and cardiovascular and metabolic measures. Analyses were considered among obese [body mass index (BMI)≥30 kg/m(2)] and non-obese (BMI<30 kg/m(2)) men and women.

RESULTS

The prevalence of osteophytes-defined radiographic knee OA was 34%. Leptin levels and homeostatic model assessment-insulin resistance (HOMA-IR), a proxy measure of insulin resistance, were significantly associated with knee OA; those with knee OA had 35% higher HOMA-IR values and 52% higher leptin levels compared to those without knee OA. The magnitude of the association between HOMA-IR and knee OA was strongest among men, regardless of obesity status; odds ratios (ORs) for HOMA-IR were 34% greater among non-obese men (OR=1.18) vs obese women (OR=0.88). Among obese women, a 5-μg/L higher leptin was associated with nearly 30% higher odds of having knee OA (OR=1.28). Among men, ORs for the association of leptin and knee OA were in the opposite direction.

CONCLUSIONS

Cardiometabolic dysfunction is related to osteophytes-defined radiographic knee OA prevalence and persists within subgroups defined by obesity status and gender. A sex dimorphism in the direction and magnitude of cardiometabolic risk factors with respect to knee OA was described including HOMA-IR being associated with OA prevalence among men while leptin levels were most important among women.

Effects of Tai Chi on Gait Kinematics, Physical Function, and Pain in Elderly with Knee Osteoarthritis — A Pilot Study

Our previous study has demonstrated that 6 weeks of Tai Chi exercise significantly improves knee pain and stiffness in elderly with knee osteoarthritis. This study also examine the effects of Tai Chi exercise on gait kinematics, physical function, pain, and pain self-efficacy in elderly with knee osteoarthritis. In this prospective, pretest-posttest clinical trial, 40 men and women (64.4 ± 8.3 years) diagnosed with knee osteoarthritis participated in 6 weeks of instructed Tai Chi training, 1 hour/session, 2 sessions/week. The following measures were taken at baseline and the conclusion of the intervention: (a) gait kinematics including stride length, stride frequency, and gait speed quantified using video analysis, (b) physical function, (c) knee pain, and (d) pain self-efficacy. Data were analyzed using repeated MANCOVA, MANOVA, ANOVA and Wilcoxon tests. After 6 weeks of Tai Chi exercise, stride length ( p = 0.023; 1.17 ± 0.17 vs. 1.20 ± 0.14 m ), stride frequency ( p = 0.014; 0.91 ± 0.08 vs. 0.93 ± 0.08 strides/s), and consequently gait speed (p < 0.025; 1.06 ± 0.19 vs. 1.12 ± 0.15 m/s ) increased in the participants. Physical function was significantly improved ( p < 0.001) and knee pain was significantly decreased ( p = 0.002), while no change was observed in pain self-efficacy. In conclusion, these findings support that Tai Chi is beneficial for gait kinematics in elderly with knee osteoarthritis, and a longer term application is needed to substantiate the effect of Tai Chi as an alternative exercise in management of knee osteoarthritis.

Strength training following hematopoietic stem cell transplantation

BACKGROUND

Patients receiving high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT) experience considerable reductions in physical activity and deterioration of their health status.

OBJECTIVE

The purpose of this pilot study was to test the effects of strength training compared with usual activity on physical activity, muscle strength, fatigue, health status perceptions, and quality of life following HSCT.

METHODS

Nineteen subjects were randomized to the exercise or control group. Moderate-intensity strength training began following discharge from the hospital. Dependent variables included physical activity, muscle strength, fatigue, health status perceptions, and quality of life. Variables were measured prior to admission to the hospital for HSCT, day 8 following HSCT, and 6 weeks following discharge from the hospital.

RESULTS

Significant time effects were noted for many variables with anticipated declines in physical activity, muscle strength, fatigue, and health status perceptions immediately after HSCT with subsequent improvements 6 weeks following hospital discharge. One group effect was noted with subjects in the exercise group reporting less fatigue than subjects in the control group. Although no significant interactions were detected, the trends suggest that the exercise group may be more physically active following the intervention compared with the usual-activity group.

CONCLUSIONS

This study demonstrates the potential positive effects of strength training on physical activity, fatigue, and quality of life in people receiving high-dose chemotherapy and HSCT.

IMPLICATIONS FOR PRACTICE

Preliminary evidence is provided for using strength training to enhance early recovery following HSCT. Elastic resistance bands are easy to use and relatively inexpensive.

Associations of anatomical measures from MRI with radiographically defined knee osteoarthritis score, pain, and physical functioning

BACKGROUND

The prevalence of knee osteoarthritis is traditionally based on radiographic findings, but magnetic resonance imaging is now being used to provide better visualization of bone, cartilage, and soft tissues as well as the patellar compartment. The goal of this study was to estimate the prevalences of knee features defined on magnetic resonance imaging in a population and to relate these abnormalities to knee osteoarthritis severity scores based on radiographic findings, physical functioning, and reported knee pain in middle-aged women.

METHODS

Magnetic resonance images of the knee were evaluated for the location and severity of cartilage defects, bone marrow lesions, osteophytes, subchondral cysts, meniscal and/or ligamentous tears, effusion, and synovitis among 363 middle-aged women (724 knees) from the Michigan Study of Women's Health Across the Nation. These findings were related to Kellgren-Lawrence osteoarthritis severity scores from radiographs, self-reported knee pain, self-reported knee injury, perception of physical functioning, and physical performance measures to assess mobility. Radiographs, physical performance assessment, and interviews were undertaken at the 1996 study baseline and again (with the addition of magnetic resonance imaging assessment) at the follow-up visit during 2007 to 2008.

RESULTS

The prevalence of moderate-to-severe knee osteoarthritis changed from 3.7% at the baseline assessment to 26.7% at the follow-up visit eleven years later. Full-thickness cartilage defects of the medial, lateral, and patellofemoral compartments were present in 14.5% (105 knees), 4.6% (thirty-three knees), and 26.2% (190 knees), respectively. Synovitis was identified in 24.7% (179) of the knees, and joint effusions were observed in 70% (507 knees); 21.7% (157) of the knees had complex or macerated meniscal tears. Large osteophytes, marked synovitis, macerated meniscal tears, and full-thickness tibial cartilage defects were associated with increased odds of knee pain and with 30% to 40% slower walking and stair-climbing times.

CONCLUSIONS

Middle-aged women have a high prevalence of moderate-to-severe knee osteoarthritis corroborated by strong associations with cartilage defects, complex and macerated meniscal tears, osteophytes and synovitis, knee pain, and lower mobility levels.

Relationship of Physical Performance with Body Composition and Bone Mineral Density in Individuals over 60 Years of Age: A Systematic Review

The purpose of this review was to examine the relationship between physical performance and body composition measurements, including fat/muscle mass and bone mineral density (BMD) in individuals ≥60 years of age. Various measurements used to assess body composition, BMD, and physical performance (PP) were discussed as well. Medline/PubMed, CINAHL, and SCIE were used to identify articles. After limiting the search for age and kind of physical performance measures, 33 articles were evaluated. Higher fat mass was associated with poorer physical performance while higher muscle mass was a predictor of better physical performance, especially in the lower extremities. Additionally, evidence showed that higher muscle fat infiltration was a determinant of poorer physical performance. BMD was shown to be a good predictor of physical performance although the relationship was stronger in women than in men. Developing standardized methods for PP measurements could help in further investigation and conclusions of its relationship with body composition.

Association Between Muscle Mass, Leg Strength, and Fat Mass With Physical Function in Older Adults: Influence of Age and Sex

Objective: The purposes of this study were to determine the relationship between muscle mass, muscle strength, muscle quality, and fat mass with a composite measure of physical function in older adults, and to determine whether these relations differed by age and sex. Method: Participants consisted of 1280 adults aged ≥ 55 yr from the NHANES study. Reduced rank regression was used to identify patterns of muscle mass, muscle strength, muscle quality, and fat mass related to physical function. Results: A single relevant pattern emerged that included leg strength and fat mass as predictors of the 7 physical function variables. The leg strength loading was significantly greater than the fat mass loading in men and women aged 55-64 and ≥75, and differed between sexes. Conclusion: Leg strength and fat mass best predict physical function in older adults and the relative importance varies according to age and sex.

A clinical trial of neuromuscular electrical stimulation in improving quadriceps muscle strength and activation among women with mild and moderate osteoarthritis

BACKGROUND

Neuromuscular electrical stimulation (NMES) has demonstrated efficacy in improving quadriceps muscle strength (force-generating capacity) and activation following knee replacement and ligamentous reconstruction. Yet, data are lacking to establish the efficacy of NMES in people with evidence of early radiographic osteoarthritis.

OBJECTIVE

The purpose of this study was to determine whether NMES is capable of improving quadriceps muscle strength and activation in women with mild and moderate knee osteoarthritis.

DESIGN

This study was a randomized controlled trial.

METHODS

Thirty women with radiographic evidence of mild or moderate knee osteoarthritis were randomly assigned to receive either no treatment (standard of care) or NMES treatments 3 times per week for 4 weeks. The effects of NMES on quadriceps muscle strength and activation were evaluated upon study enrollment, as well as at 5 and 16 weeks after study enrollment, which represent 1 and 12 weeks after cessation of NMES among the treated participants. The Western Ontario and McMaster Universities Osteoarthritis Index and a 40-foot (12.19-m) walk test were used at each testing session.

RESULTS

Improvements in quadriceps muscle strength or activation were not realized for the women in the intervention group. Quadriceps muscle strength and activation were similar across testing sessions for both groups.

LIMITATIONS

Women were enrolled based on radiographic evidence of osteoarthritis, not symptomatic osteoarthritis, which could have contributed to our null finding. A type II statistical error may have been committed despite an a priori power calculation. The assessor and the patients were not blinded to group assignment, which may have introduced bias into the study.

CONCLUSIONS

Four weeks of NMES delivered to women with mild and moderate osteoarthritis and mild strength deficits was insufficient to induce gains in quadriceps muscle strength or activation. Future research is needed to examine the dose-response relationship for NMES in people with early radiographic evidence of osteoarthritis.

Racial differences in gait mechanics associated with knee osteoarthritis

BACKGROUND AND AIMS

This study examines racial differences in gait mechanics in persons with knee osteoarthritis and the influence of anthropometrics, educational level, radiographic disease severity (rOA), and self-report measures of pain and disability on racial differences in gait.

METHODS

One hundred seventy five (64 black and 111 white) adults with radiographic knee OA were tested. 3-D kinematic and kinetic data were collected while subjects walked at two self-selected speeds (normal and fast). Anthropometric data, radiographic level of OA, and self-report measures of pain and disability were also collected. Gait patterns were compared across groups and within groups.

RESULTS

Black and white subjects did not differ significantly in radiographic OA. However, blacks walked significantly more slowly when asked to walk fast. At the normal speed, blacks had a smaller knee range of motion and loading rate than whites. Blacks also took longer to reach their peak maximum ground reaction force than whites. Within black subjects variations in gait mechanics were primarily explained by BMI, rOA, selfreported psychological disability, and pain self-efficacy. In white subjects, variations in gait mechanics were primarily explained by weight, age, velocity, psychological disability, and self-efficacy.

CONCLUSIONS

Blacks in this study had a pattern of gait mechanics generally associated with high levels of osteoarthritis, though they did not differ significantly in rOA from whites. The variability in gait patterns exhibited by blacks was most strongly related to variance in walking speed, anthropometrics, and perceived physical ability. Taken together, these results suggest that race is an important factor that must be considered in the treatment and study of osteoarthritis.