Association of Plasma Small-Molecule Intermediate Metabolites With Age and Body Mass Index Across Six Diverse Study Populations

BACKGROUND

Older age and obesity are associated with metabolic dysregulation; the mechanism by which these factors impact metabolism across the lifespan is important, but relatively unknown. We evaluated a panel of amino acids (AAs) and acylcarnitines (ACs) to identify effects of age and adiposity (body mass index) on circulating small-molecule metabolites in a meta-analysis of six diverse study populations.

METHODS

Targeted metabolic profiling was performed in six independent studies, representing 739 subjects with a broad range of age, body mass index, health states, and ethnic origin. Principal components analysis was performed on log-normalized values for AAs and ACs separately, generating one AC factor and two AA factors for each study. A common AC factor consisted primarily of acetylcarnitine, medium-chain AC, and several long-chain AC. AA Factor 1 consisted primarily of large neutral AAs. Glycine was its own factor.

RESULTS

Metabolic profiling and factor analysis identified clusters of related metabolites of lipid and AA metabolism that were consistently associated with age and body mass in a series of studies with a broad range of age, body mass index, and health status. An inverse association of glycine with body mass index and male gender supports its role as a marker of favorable metabolic health.

CONCLUSIONS

An important focus of future investigations should be to determine whether these clusters of metabolic intermediates are possible early predictors of health outcomes associated with body mass; are involved with accelerated aging; are involved in the causative pathway of aging; and how modification of these metabolic pathways impact the biology of aging.

Physical Resilience in Older Adults: Systematic Review and Development of an Emerging Construct

BACKGROUND

Resilience has been described in the psychosocial literature as the capacity to maintain or regain well-being during or after adversity. Physical resilience is a newer concept that is highly relevant to successful aging. Our objective was to characterize the emerging construct of resilience as it pertains to physical health in older adults, and to identify gaps and opportunities to advance research in this area.

METHODS

We conducted a systematic review to identify English language papers published through January 2015 that apply the term "resilience" in relation to physical health in older adults. We applied a modified framework analysis to characterize themes in implicit or explicit definitions of physical resilience.

RESULTS

Of 1,078 abstracts identified, 49 articles met criteria for inclusion. Sixteen were letters or concept papers, and only one was an intervention study. Definitions of physical resilience spanned cellular to whole-person levels, incorporated many outcome measures, and represented three conceptual themes: resilience as a trait, trajectory, or characteristic/capacity.

CONCLUSIONS

Current biomedical literature lacks consensus on how to define and measure physical resilience. We propose a working definition of physical resilience at the whole person level: a characteristic which determines one's ability to resist or recover from functional decline following health stressor(s). We present a conceptual framework that encompasses the related construct of physiologic reserve. We discuss gaps and opportunities in measurement, interactions across contributors to physical resilience, and points of intervention.

Group trajectory analysis helps to identify older cancer survivors who benefit from distance-based lifestyle interventions

BACKGROUND

The number of older cancer survivors is increasing as more adults survive to older ages. The objectives of this study were to examine trajectories of physical activity (PA) and physical function (PF) over a 2-year lifestyle counseling study and to identify characteristics of the trajectory groups.

METHODS

This was a secondary analysis of Reach Out to Enhance Wellness, a randomized controlled trial of home-based lifestyle counseling. The 641 participants were older (≥65 years), overweight (body mass index [BMI], 25 to <40 kg/m(2)), long-term community-dwelling survivors (>5 years) of breast, prostate, and colorectal cancer from Canada, the United Kingdom, and the United States (21 states) who had been randomly assigned to an immediate intervention or a 12-month-wait-listed control arm. The main outcome measures were PA and PF trajectory group membership.

RESULTS

Three PA groups and 5 PF trajectory groups were observed. The baseline BMI (P < .001) and self-efficacy for performing strength (P < .0001) and endurance exercises (P < .0002) were the strongest predictors of achieving the highest amount of PA and the most favorable functional trajectory over 2 years. Individuals with low baseline self-efficacy, no PA, and a Short Form 36 PF subscale score < 65 did not benefit from the intervention.

CONCLUSIONS

This study identified characteristics of survivors who benefited from home-based interventions and suggested alternative approaches for survivors requiring more structured and intensive interventions to promote behavioral changes.

Symptoms, weight loss, and physical function in a lifestyle intervention study of older cancer survivors

OBJECTIVES

Many older cancer survivors are overweight or obese, with additional illness burden increasing functional decline, which may affect their ability to engage in lifestyle interventions. This study examined how overweight long-term survivors' symptom severity associated with comorbidity prior to a diet and exercise intervention was associated with post-intervention function and examined symptoms' effects on function through change in physical activity, diet quality, and weight status.

MATERIALS AND METHODS

This is a secondary data analysis of 514 breast, prostate, and colorectal cancer survivors who participated in the one-year home-based diet and exercise intervention Reach-Out to Enhance Wellness trial. Measures included symptoms, weight, physical activity, diet quality, overall physical function (PF), and basic and advanced lower extremity function (BLEF and ALEF). Simple and serial mediation analyses were conducted to examine direct effects of symptom severity on PF, BLEF, and ALEF and indirect effects of symptom severity through changes in diet quality, physical activity, and weight.

RESULTS

Symptom severity was directly associated with lower functioning scores for PF (b=-0.63 p<0.001), BLEF (b=-0.33, p<0.001), and ALEF (b=-0.22, p<0.001). Indirect effects of symptom severity through weight loss, physical activity, and diet were not significant. Weight loss and physical activity were associated with higher PF and ALEF and diet quality was associated with higher BLEF.

CONCLUSION

Symptom severity of older, overweight cancer survivors negatively affects physical function. However, greater weight loss and more physical activity were associated with higher functioning scores, regardless of symptom severity.

Endothelial Progenitor Cell Levels Predict Future Physical Function: An Exploratory Analysis From the VA Enhanced Fitness Study

BACKGROUND

Levels of circulating progenitor cells (CPCs) are depleted with aging and chronic injury and are associated with level of physical functioning; however, little is known about the correlation of CPCs with longer-term measures of physical capabilities. We sought to determine the association of CPCs with future levels of physical function and with changes in physical function over time.

METHODS

CPCs were measured in 117 participants with impaired glucose tolerance in the Enhanced Fitness clinical trial based on the cell surface markers CD34 and CD133 and aldehyde dehydrogenase (ALDH) activity at baseline, 3 months, and 12 months. Physical function was assessed using usual and rapid gait speed, 6-minute walk distance, chair stand time, and SF-36 physical functioning score and reassessed at 3 and 12 months after clinical intervention.

RESULTS

Higher baseline levels of CD133(+), CD34(+), CD133(+)CD34(+), and ALDH(br) were each highly predictive of faster gait speed and longer distance walked in 6 minutes at both 3 and 12 months. These associations remained robust after adjustment for age, body mass index, baseline covariates, and inflammation and were independent of interventions to improve physical fitness. Further, higher CPC levels predicted greater improvements in usual and rapid gait speed over 1 year.

CONCLUSIONS

Baseline CPC levels are associated not only with baseline mobility but also with future physical function, including changes in gait speed. These findings suggest that CPC measurement may be useful as a marker of both current and future physiologic aging and functional decline.

Activity-related energy expenditure in older adults: a call for more research

The purposes of this article were to 1) provide an overview of the science of physical activity-related energy expenditure in older adults (≥65 yr), 2) offer suggestions for future research and guidelines for how scientists should be reporting their results in this area, and 3) present strategies for making these data more accessible to the layperson. This article was meant to serve as a preliminary blueprint for future empirical work in the area of energy expenditure in older adults and translational efforts to make these data useful and accurate for older adults. This document was based upon deliberations of experts involved in the Strategic Health Initiative on Aging Committee of the American College of Sports Medicine. The article was designed to reach a broad audience who might not be familiar with the complexities of assessing energy expenditure, especially in older adults.

Differences between completely physically inactive and low active older men and their response to an exercise intervention: the Veterans LIFE study

BACKGROUND

Physical activity interventions typically do not report behavioral changes in activity sub-groups. The aim of this study was to compare baseline differences and changes in physical activity between truly physically inactive men and low active men enrolled in a twelve-month, home-based physical activity intervention.

METHODS

Veterans with a mean age of 77.6 years were randomized to either a physical activity intervention or usual care. Measures included self-reported physical activity, physical function, and physical performance.

RESULTS

At baseline, the physically inactive group reported more symptoms and poorer functioning than the low active group. At 12 months, physically inactive men randomized to the intervention group increased their physical activity to an average of 73.3 minutes per week. Physically inactive individuals randomized to the control group were eight times more likely to remain inactive compared to the low active group.

CONCLUSIONS

Completely physically inactive older men can markedly increase physical activity levels with a long-term intervention. Without such intervention, the likelihood of this group remaining inactive is eightfold.

A randomized controlled trial on Stroke telerehabilitation: The effects on falls self-efficacy and satisfaction with care

We determined the effect of a multifaceted stroke telerehabilitation (STeleR) intervention on falls-related self-efficacy and satisfaction with care. We conducted a prospective, randomized, multisite, single-blinded trial in 52 veterans from three Veterans Affairs Medical Centers. Participants who experienced a stroke in the past 24 months were randomized to the STeleR intervention or usual care. Participants in the intervention arm were administered an exit interview to gather specific patient satisfaction data three months after their final outcome measure. The STeleR intervention consisted of three home visits, five telephone calls, and an in-home messaging device provided over three months to instruct patients in functionally based exercises and adaptive strategies. The outcome measures included Falls Efficacy Scale to measure fall-related self-efficacy and a Stroke-Specific Patient Satisfaction with Care (SSPSC) scale, a measure separated into two subscales (satisfaction with home care and satisfaction with hospital care) was employed to measure the participants' satisfaction. At six months, compared with the usual care group, the STeleR group showed statistically significant improvements in one of the two SSPSC scales (satisfaction with hospital care, p = .029) and approached significance in the second SSPSC scale (satisfaction with home care, p = .077). There were no improvements in fall-related self-efficacy. Core concepts identified were: (a) beneficial impact of the trained assistant; (b) exercises helpful; (c) home use of technology. The STeleR intervention improved satisfaction with care, especially as it relates to care following their experience from the hospital. With the limited resources available for in-home rehabilitation for stroke survivors, STeleR (and especially its exercise components) can be a useful complement to traditional post-stroke rehabilitation.

Symptoms, Weight Loss and Physical Function in a Lifestyle Intervention Study of Older Cancer Survivors

Cancer is most often a disease of aging, and frequently, a disease for which obesity serves as a risk factor. Thus, many cancer survivors are older, overweight or obese, with higher illness burden, symptoms, and comorbidities. Against this backdrop, survivors are at increased risk for functional decline. The question is whether lifestyle interventions can still benefit older, sicker survivors? The purpose of this study was to examine how overweight long-term survivors' symptom severity prior to a diet and exercise intervention is associated with post-intervention function and to determine symptoms' effects on function through change in physical activity, diet quality, and weight status. Methods This is a secondary data analysis of 514 breast, prostate, and colorectal cancer survivors who participated in the one-year home-based diet and exercise intervention, Reach-Out to Enhance Wellness (RENEW) trial. Pre- and post-intervention data were analyzed. Measures of this study included pre-intervention symptoms, changes in weight, physical activity, diet quality, and post-intervention overall physical function (PF), and basic and advanced lower extremity function (BLEF and ALEF). Simple and serial mediation analyses were conducted to examine direct effects of symptom severity on BLEF and ALEF and the indirect effects of symptom severity through changes in diet quality, physical activity, and weight status. Results Increased symptom severity was directly associated with lower functioning scores for PF (b = −0.63 P &lt; 0.001), BLEF (b = −0.33, P &lt; 0.001) and ALEF (b = −0.22, P &lt; 0.001). Indirect effects of symptom severity through weight loss, physical activity and diet were not significant. Weight loss and increased physical activity were significantly associated with higher PF and ALEF and higher diet quality was associated with higher BLEF. Conclusion Symptom severity of older, overweight cancer survivors negatively affects physical function. However, greater weight loss and physical activity were associated with higher functioning scores, regardless of symptom severity. Findings build from the recent emphasis on the negative effects of obesity on survivor outcomes to highlight weight loss as an important factor in maintaining function in older cancer survivors.

A Novel Analytic Technique to Measure Associations Between Circulating Biomarkers and Physical Performance Across the Adult Life Span

Understanding associations between circulating biomarkers and physical performance across the adult life span could aid in better describing mechanistic pathways leading to disability. We hypothesized that high concentrations of circulating biomarkers would be associated with lower functioning across study populations representing the adult life span. The data were from four intervention and two observational studies with ages ranging 22-89 years. Biomarkers assayed included inflammatory, coagulation, and endothelial function markers. Physical performance was measured either by VO2peak (studies of young and middle-aged adults) or usual gait speed (studies of older adults). Partialled (by age, body mass index, race, and sex) and weighted common correlations were calculated between biomarkers and physical performance. Homogeneity of the associations was also assessed. Interleukin-6 (weighted r = -.22), tumor necrosis factor receptor 2 (weighted r = -.19), D-dimer (weighted r = -.16), tumor necrosis factor receptor 1 (weighted r = -.15), granulocyte colony-stimulating factor (weighted r = -.14), and tumor necrosis factor alpha (weighted r = -.10) were all significantly inversely correlated with physical performance (p < .05). All significant correlations were homogeneous across studies. In summary, we observed consistent inverse associations between six circulating biomarkers and objective measures of physical performance. These results suggest that these serum biomarkers may be broadly applicable for detection, trajectory, and treatment monitoring of physical function across the life span or possibly for midlife predictors of functionally deleterious conditions.

PTSD is negatively associated with physical performance and physical function in older overweight military Veterans

This study examines the effect of posttraumatic stress disorder (PTSD) on function and physical performance in older overweight military Veterans with comorbid conditions. This is a secondary data analysis of older Veterans (mean age = 62.9 yr) participating in a physical activity counseling trial. Study participants with PTSD (n = 67) and without PTSD (n = 235) were identified. Self-reported physical function (36-item Short Form Health Survey) and directly measured physical performance (mobility, aerobic endurance, strength) were assessed. Multivariate analyses of variance controlling for demographic factors and psychiatric disorders demonstrated significant physical impairment among those with PTSD. PTSD was negatively associated with self-reported physical function, functioning in daily activities, and general health (p < 0.01). Those with PTSD also performed significantly worse on tests of lower-limb function (p < 0.05). Despite being significantly younger, Veterans with PTSD had comparable scores on gait speed, aerobic endurance, grip strength, and bodily pain compared with Veterans without PTSD. This study provides preliminary data for the negative association between PTSD and physical function in older military Veterans. These data highlight the importance of ongoing monitoring of physical performance among returning Veterans with PTSD and intervening in older overweight Veterans with PTSD, whose physical performance scores are indicative of accelerated risk of premature functional aging.

Light-intensity activity attenuates functional decline in older cancer survivors

While moderate- to vigorous-intensity physical activities (MVPA) confer the greatest health benefits, evidence suggests that light-intensity activities are also beneficial, particularly for older adults and individuals with moderate to severe comorbidities.

PURPOSE

To examine cross-sectional and longitudinal associations between light-intensity activity and physical function in older cancer survivors at increased risk for age- and treatment-related comorbidities, including accelerated functional decline.

METHODS

The analysis included data from 641 breast, prostate, and colorectal cancer survivors (54% female) age 65 yr and older who participated in a 1-yr home-based diet and exercise intervention designed to reduce the rate of physical function decline. ANCOVA was used to compare means of physical function across levels of PA intensity (low-light [LLPA]: 1.5-2.0 METs; high-light [HLPA]: 2.1-2.9 METs; MVPA: ≥3.0 METs).

RESULTS

In cross-sectional analyses, increasing tertiles of light-intensity activity were associated with higher scores for all three measures of physical function (all P values <0.005), after adjusting for age, sex, body mass index, comorbidity, symptoms, and MVPA. Associations were stronger for HLPA than for LLPA. Compared with survivors who had decreased MVPA or maintained stable MVPA and HLPA at the postintervention follow-up, those who had increased HLPA, but had decreased MVPA or maintained stable MVPA, reported higher physical function scores (LS means [95% confidence interval]: SF-36 Physical Function Subscale: -5.58 [-7.96 to -3.20] vs -2.54 [-5.83 to 0.75], P = 0.14; Basic Lower Extremity Function: -2.00 [-3.45 to -0.55] vs 0.28 [-1.72 to 2.28], P = 0.07; Advanced Lower Extremity Function: -2.58 [-4.00 to -1.15] vs 0.44 [-1.52 to 2.40], P = 0.01).

CONCLUSIONS

Our findings suggest that increasing light-intensity activities, especially HLPA, may be a viable approach to reducing the rate of physical function decline in individuals who are unable or reluctant to initiate or maintain adequate levels of moderate-intensity activities.

Assisted early mobility for hospitalized older veterans: preliminary data from the STRIDE program

An important contributor to hospital-associated disability is immobility during hospitalization. Preliminary results from STRIDE, a clinical demonstration program of supervised walking for older adults admitted to the hospital with medical illness, are reported. The STRIDE program consisted of a targeted gait and balance assessment by a physical therapist, followed by daily walks supervised by a recreation therapy assistant for the duration of the hospital stay. To examine program effectiveness, STRIDE participants (n = 92) were compared with individuals referred but not enrolled (because of refusal or because program was at capacity, n = 35). Median length of stay was 4.7 days for STRIDE participants and 5.7 days for individuals receiving usual care (P = .31). There was one inpatient fall in each group (not associated with a STRIDE walk). Overall, 92% of STRIDE participants were discharged to home (rather than a skilled nursing facility (SNF)) compared to 74% of individuals receiving usual care (P = .007). Thirty-day emergency department visit rates and readmission rates were not significantly different between the two groups. STRIDE, a supervised walking program for hospitalized older adults, was feasible and safe, and program participants were less likely to be discharged to a SNF than a demographically similar comparison group. STRIDE is a promising interdisciplinary approach to promoting mobility and improving outcomes in hospitalized older adults.

Diet and exercise intervention adherence and health-related outcomes among older long-term breast, prostate, and colorectal cancer survivors

BACKGROUND

Diet and exercise interventions for cancer survivors result in health benefits; however, few studies have examined health outcomes in relation to adherence.

PURPOSE

We examined associations between adherence to components of a diet-exercise intervention and survivors' physical and mental health.

METHODS

A randomized controlled trial tested a telephone and mailed print intervention among 641 older, overweight, long-term survivors of breast, prostate, and colorectal cancer. Dietary and exercise behaviors were assessed at 14 time points throughout the year-long intervention; health outcomes were examined postintervention.

RESULTS

Telephone session attendance had significant indirect relationships with health outcomes through intervention-period exercise and dietary behavior. Attendance showed positive indirect relationships with physical function (β = 0.11, p < 0.05), basic and advanced lower extremity function (β = 0.10, p < 0.05/β = 0.09, p < 0.05), and mental health (β = 0.05, p < 0.05), and a negative indirect relationship with body mass index (β = -0.06, p < 0.05).

CONCLUSIONS

Session attendance is vital in facilitating improvement in health behaviors and attendant outcomes (Clinicaltrials.gov number NCT00303875).

Depletion of circulating progenitor cells precedes overt diabetes: a substudy from the VA enhanced fitness trial

BACKGROUND

One theory of aging and disease development is that chronic injury (pathology) results in activation of regenerative processes and initial repair, with overt disease arising only after exhaustion of reparative capability leads to inadequate repair. While depletion of circulating progenitor cells (CPCs) has been noted in diabetes, the degree to which CPC depletion predates and is associated with propensity to develop overt disease is unclear.

METHODS

The Enhanced Fitness trial enrolled overweight/obese (body mass index >25) sedentary patients with glucose intolerance but without overt diabetes. Baseline CPCs were measured in 129 patients based on the cell surface markers CD34, CD133, and aldehyde dehydrogenase (ALDH) activity. HgbA1C, fasting insulin and glucose levels, and HOMA calculations were ascertained.

RESULTS

Lower counts of early angiogenic CPCs identified as CD34(+), CD34(+)CD133(+), and ALDH-bright (ALDH(br)) cells were associated with impairments in glucose homeostasis as reflected by HgbA1C, but not fasting insulin, glucose, or HOMA-IR. These associations remained when corrected for age and cardiovascular risk factors.

CONCLUSIONS/INTERPRETATION

The numbers of CD34(+) and ALDH(br) CPCs were significantly lower in patients with impaired glucose tolerance. Depletion of reparative capacity as reflected by loss of CPCs may presage overt disease as exemplified in this pre-diabetes model.

Lower levels of circulating progenitor cells are associated with low physical function and performance in elderly men with impaired glucose tolerance: a pilot substudy from the VA Enhanced Fitness trial

BACKGROUND

Aging is marked by a decline in physical function. Although the biological underpinnings for this remain unclear, loss of regenerative capacity has been proposed as one cause of the loss of physical function that occurs over time. The quantity of circulating progenitor cells (CPCs) may be one reflection of regenerative capability. We sought to determine whether certain specific CPC subpopulations were associated with physical function.

METHODS

Baseline CPCs were measured in 129 randomized participants in the Enhanced Fitness clinical trial based on the cell surface markers CD34, CD133, CD146, and CD14 and aldehyde dehydrogenase (ALDH) activity. Physical function was assessed using usual and rapid gait speed, 6-minute walk distance, chair stand time, and balance time.

RESULTS

Low counts of early angiogenic CPCs identified as CD34(+), CD34(+)CD133(+), and ALDH-bright (ALDH(br)) cells were associated with low usual gait speed (p < .005, p < .001, and p < .007), rapid gait speed (p < .001, p < .003, and p < .001), and 6-minute walking distance (all comparisons p < .001), and longer time required to complete five chair stands (p < .006, p < .002, and p < .004). CPC counts of mature endothelial or monocytic markers were not associated with physical function.

CONCLUSIONS

The numbers of CD34(+) and ALDH(br) CPCs are significantly lower in patients with impaired physical function. Further studies are needed to determine the underlying causes for this association.

METs and accelerometry of walking in older adults: standard versus measured energy cost

PURPOSE

This study aimed to measure the metabolic cost (METs) of walking activities in older adults, to examine the relationship between accelerometer output and METs across walking activities, and to compare measured MET values in older adults with the MET values in the compendium.

METHODS

Twenty older adults (mean age = 75, range = 60-90 yr) completed eight walking activities (five treadmill based, three free living) for 6 min each. Oxygen consumption (V˙O2) and resting metabolic rate (RMR) were measured using a portable metabolic system, and motion was recorded using a waist-mounted ActiGraph accelerometer (GT3X; ActiGraph, Pensicola, FL). Energy expenditure across activities was defined as kilocalories per minute and measured as METs (V˙O2 / RMR) and standard METs (V˙O2 / 3.5 mL·kg-1·min-1). Mixed modeling was used to assess differences in counts per minute and kilocalories per minute by weight status, sex, comorbidity status, and functional status. Linear regression analysis was applied to develop a prediction equation for kilocalories per minute. Energy costs of walking were subsequently compared with METs in the compendium of physical activities.

RESULTS

Average measured RMR was 2.6 mL·kg-1·min-1, 31.6% less than the standard RMR of 3.5 mL·kg-1·min-1. On average, standard METs were 71% lower than the measured METs across all walking activities. Measured MET levels differed from previously reported values in the literature and values listed in the compendium, resulting in misclassification of activity intensities for 60% of the walking conditions. Average counts for the walking activities ranged from 809 (treadmill = 1.5 mph) to 4593 counts per minute (treadmill = 3.5 mph). Previous regression equations consistently overestimate all activities compared with the measured energy cost in this sample of older adults.

CONCLUSION

This study identifies the need for equations and cut points specific to older adults.

Enhanced fitness: a randomized controlled trial of the effects of home-based physical activity counseling on glycemic control in older adults with prediabetes mellitus

OBJECTIVES

To determine whether a home-based multicomponent physical activity counseling (PAC) intervention is effective in reducing glycemic measures in older outpatients with prediabetes mellitus.

DESIGN

Controlled clinical trial.

SETTING

Primary care clinics of the Durham Veterans Affairs (VA) Medical Center between September 29, 2008, and March 25, 2010.

PARTICIPANTS

Three hundred two overweight (body mass index 25-45 kg/m(2) ), older (60-89) outpatients with impaired glucose tolerance (fasting blood glucose 100-125 mg/dL, glycosylated hemoglobin (HbA1c) <7%) randomly assigned to a PAC intervention group (n = 180) or a usual care control group (n = 122).

INTERVENTION

A 12-month, home-based multicomponent PAC program including one in-person baseline counseling session, regular telephone counseling, physician endorsement in clinic with monthly automated encouragement, and customized mailed materials. All study participants, including controls, received a consultation in a VA weight management program.

MEASUREMENTS

The primary outcome was a homeostasis model assessment of insulin resistance (HOMA-IR), calculated from fasting insulin and glucose levels at baseline and 3 and 12 months. HbA1c was the secondary indicator of glycemic control. Other secondary outcomes were anthropometric measures and self-reported physical activity, health-related quality of life, and physical function.

RESULTS

There were no significant differences between the PAC and control groups over time for any of the glycemic indicators. Both groups had small declines over time of approximately 6% in fasting blood glucose (P < .001), and other glycemic indicators remained stable. The declines in glucose were not sufficient to affect the change in HOMA-IR scores due to fluctuations in insulin over time. Endurance physical activity increased significantly in the PAC group (P < .001) and not in the usual care group.

CONCLUSION

Home-based telephone counseling increased physical activity levels but was insufficient to improve glycemic indicators in older outpatients with prediabetes mellitus.

Reach out to enhance wellness home-based diet-exercise intervention promotes reproducible and sustainable long-term improvements in health behaviors, body weight, and physical functioning in older, overweight/obese cancer survivors

PURPOSE

Diet and exercise interventions have been tested in cancer survivors as a means to reduce late effects and comorbidity, but few have assessed adherence and health outcomes long term.

METHODS

Between July 2005 and May 2007, the Reach Out to Enhance Wellness (RENEW) trial accrued 641 locoregionally staged, long-term (≥ 5 years from diagnosis) colorectal, breast, and prostate cancer survivors in the United States (21 states), Canada, and the United Kingdom. All participants were sedentary (< 150 minutes of physical activity [PA] a week), overweight or obese (body mass index, 25 to 40 kg/m(2)), and over age 65 years. The trial tested a diet-exercise intervention delivered via mailed print materials and telephone counseling. RENEW used a wait-list control, cross-over design (ie, participants received the year-long intervention immediately or after a 1-year delay), which allowed the opportunity to assess program efficacy (previously reported primary outcome), durability, and reproducibility (reported herein). Measures included diet quality (DQ), PA, BMI, and physical function (PF).

RESULTS

No significant relapse was observed in the immediate-intervention arm for DQ, PA, and BMI; however, rates of functional decline increased when the intervention ceased. From year 1 to year 2, significant improvements were observed in the delayed-intervention arm; mean change scores in behaviors and BMI and PF slopes were as follows: DQ score, 5.2 (95% CI, 3.4 to 7.0); PA, 45.8 min/wk (95% CI, 26.9 to 64.6 min/wk); BMI, -0.56 (95% CI, -0.75 to -0.36); and Short Form-36 PF, -1.02 versus -5.52 (P < .001 for all measures). Overall, both arms experienced significant improvements in DQ, PA, and BMI from baseline to 2-year follow-up (P < .001).

CONCLUSION

Older cancer survivors respond favorably to lifestyle interventions and make durable changes in DQ and PA that contribute to sustained weight loss. These changes positively reorient functional decline trajectories during intervention delivery.

Dietary patterns differ between urban and rural older, long-term survivors of breast, prostate, and colorectal cancer and are associated with body mass index

BACKGROUND

Older adult cancer survivors are at greater risk of cancer recurrence and other comorbidities that can be prevented through improved diet and weight management. The tertiary prevention needs of rural-dwelling survivors can be even greater, yet little is known about rural and urban differences in lifestyle factors among this high-risk population.

OBJECTIVES

To compare dietary patterns of urban and rural cancer survivors and to examine associations of dietary patterns with body mass index (BMI).

DESIGN

A secondary analysis was performed of baseline data from the Reach Out to Enhance Wellness (RENEW) trial, a diet and exercise intervention among overweight, long-term (≥5 years), older survivors of colorectal, breast, and prostate cancer. Survivors in the present analysis (n=729) underwent two 45- to 60-minute telephone surveys, which included two 24-hour dietary recalls. Principal components analysis and multivariable general linear models were used to derive dietary patterns and to evaluate associations between dietary patterns and BMI, respectively.

RESULTS

Principal components analysis identified three primary dietary patterns among rural dwellers (high sweets and starches, high reduced-fat dairy, cereal, nuts, and fruits, and mixed) and three among urban dwellers (high fruits and vegetables, high meat and refined grains, and high sugar-sweetened beverages). Among rural survivors, greater adherence to the high reduced-fat dairy, cereal, nuts, and fruits pattern was positively associated with lower BMI (P trend <0.05), whereas higher scores on the mixed pattern was associated with greater BMI (P trend <0.05). Greater adherence to the high fruits and vegetables pattern among urban survivors was inversely associated with BMI (P trend <0.05).

CONCLUSIONS

Urban and rural differences in dietary intake behavior should be considered in designing public health interventions among the increasing population of older cancer survivors. In addition, targeting overall dietary patterns might be one approach to help reduce the burden of obesity among this population.

Lessons learned when innovations go awry: a baseline description of a behavioral trial-the Enhancing Fitness in Older Overweight Veterans with Impaired Fasting Glucose study

Individuals diagnosed with impaired glucose tolerance (i.e., prediabetes) are at increased risk for developing diabetes. We proposed a clinical trial with a novel adaptive randomization designed to examine the impact of a home-based physical activity (PA) counseling intervention on metabolic risk in prediabetic elders. This manuscript details the lessons learned relative to recruitment, study design, and implementation of a 12-month randomized controlled PA counseling trial. A detailed discussion on how we responded to unforeseen challenges is provided. A total of 302 older patients with prediabetes were randomly assigned to either PA counseling or usual care. A novel adaptive design that reallocated counseling intensity based on self-report of adherence to PA was initiated but revised when rates of non-response were lower than projected. This study presents baseline participant characteristics and discusses unwelcome adaptations to a highly innovative study design to increase PA and enhance glucose metabolism when the best-laid plans went awry.

Plasma acylcarnitines are associated with physical performance in elderly men

BACKGROUND

Metabolic profiling might provide insight into the biologic underpinnings of disability in older adults.

METHODS

A targeted mass spectrometry-based platform was used to identify and quantify 45 plasma acylcarnitines in 77 older men with a mean age of 79 years and average body mass index of 28.4 kg/m(2). To control for type I error inherent in a test of multiple analytes, principal components analysis was employed to reduce the acylcarnitines from 45 separate metabolites, into a single "acylcarnitine factor." We then tested for an association between this acylcarnitine factor and multiple indices of physical performance and self-reported function.

RESULTS

The acylcarnitine factor accounted for 40% of the total variance in 45 acylcarnitines. Of the metabolites analyzed, those that contributed most to our one-factor solution were even-numbered medium and long-chain species with side chains containing 10-18 carbons (factor loadings ≥0.70). Odd-numbered chain species, in contrast, had factor loadings 0.50 or less. Acylcarnitine factor scores were inversely related to physical performance as measured by the Short Physical Performance Battery total score, two of its three component scores (gait and chair stands Short Physical Performance Battery), and usual and maximal gait speeds (ρ = -0.324, -0.348, -0.309, -0.241, and -0.254, respectively; p < .05).

CONCLUSIONS

Higher acylcarnitine factor scores were associated with lower levels of objectively measured physical performance in this group of older, largely overweight men. Metabolic profiles of rodents exhibiting lipid-induced mitochondrial dysfunction show a similar phenotypic predominance of medium- and long-chain acylcarnitines.

Long-term changes in physical activity following a one-year home-based physical activity counseling program in older adults with multiple morbidities

This study assessed the sustained effect of a physical activity (PA) counseling intervention on PA one year after intervention, predictors of sustained PA participation, and three classes of post-intervention PA trajectories (improvers, maintainers, and decliners) in 238 older Veterans. Declines in minutes of PA from 12 to 24 months were observed for both the treatment and control arms of the study. PA at 12 months was the strongest predictor of post-intervention changes in PA. To our surprise, those who took up the intervention and increased PA levels the most, had significant declines in post-intervention PA. Analysis of the three post-intervention PA trajectories demonstrated that the maintenance group actually reflected a group of nonresponders to the intervention who had more comorbidities, lower self-efficacy, and worse physical function than the improvers or decliners. Results suggest that behavioral counseling/support must be ongoing to promote maintenance. Strategies to promote PA appropriately to subgroups of individuals are needed.

Walking in old age and development of metabolic syndrome: the health, aging, and body composition study

BACKGROUND

The specific health benefits of meeting physical activity guidelines are unclear in older adults. We examined the association between meeting, not meeting, or change in status of meeting physical activity guidelines through walking and the 5-year incidence of metabolic syndrome in older adults.

METHODS

A total of 1,863 Health, Aging, and Body Composition (Health ABC) Study participants aged 70-79 were followed for 5 years (1997-1998 to 2002-2003). Four walking groups were created based on self-report during years 1 and 6: Sustained low (Year 1, <150 min/week, and year 6, <150 min/week), decreased (year 1, >150 min/week, and year 6, <150 min/week), increased (year 1, <150 min/week, and year 6, >150 min/week), and sustained high (year 1, >150 min/week, and year 6, >150 min/week). Based on the Adult Treatment Panel III (ATP III) panel guidelines, the metabolic syndrome criterion was having three of five factors: Large waist circumference, elevated blood pressure, triglycerides, blood glucose, and low high-density lipoprotein (HDL) levels.

RESULTS

Compared to the sustained low group, the sustained high group had a 39% reduction in odds of incident metabolic syndrome [adjusted odds ratio (OR) = 0.61; 95% confidence interval (CI), 0.40-0.93], and a significantly lower likelihood of developing the number of metabolic syndrome risk factors that the sustained low group developed over 5 years (beta = -0.16, P = 0.04).

CONCLUSIONS

Meeting or exceeding the physical activity guidelines via walking significantly reduced the odds of incident metabolic syndrome and onset of new metabolic syndrome components in older adults. This protective association was found only in individuals who sustained high levels of walking for physical activity.