Weight loss in older age can cause bone loss. In older adults with overweight/obesity in a weight loss trial, 6-month hip bone strength increased with higher protein intake versus controls consuming the Recommended Dietary Allowance. However, greater weight loss was associated with greater 18-month hip bone mineral density loss. PURPOSE:Weight loss (WL) to treat obesity in older age can exacerbate bone loss. METHODS:This trial assessed the effects of higher protein intake on hip bone outcomes in 187 older adults with overweight/obesity participating in 6 months of active WL (caloric restriction + aerobic exercise) followed by a 12-month maintenance phase. Participants were randomized to either the Recommended Dietary Allowance for protein intake of 0.8 g protein/kg body weight/day (RecProt) or higher protein intake of 1.2 g protein/kg/day for the 6-month WL period only (6-mo HiProt) or the full 18-month period (18-mo HiProt). CT scans at baseline, 6 months, and 18 months were analyzed for hip volumetric bone mineral density (vBMD) and cortical thickness; bone strength was assessed via finite element modeling of a sideways fall. Areal (a)BMD was measured with hip dual-energy X-ray absorptiometry. Analyses examined 6-month and 18-month bone changes using analysis of covariance, and Spearman's correlations of WL vs. bone changes. RESULTS:Greater WL was associated with greater gains in hip bone strength (p = 0.007) at 6 months, but greater trabecular vBMD loss at 18 months (p = 0.011) and aBMD loss at 6 and 18 months (p < 0.001). Hip bone strength increased 3.8 ± 1.7% over 6 months in the 18-mo HiProt group vs. 0.5 ± 1.6% in the RecProt group (p = 0.02) despite similar 6-month WL across groups (-8.0 ± 5.0%); however, there were no differences between the other groups. Eighteen-month group differences were non-significant. CONCLUSION:Higher protein intake had a beneficial effect on hip bone strength in older adults with overweight/obesity undergoing a WL intervention over the short-term.

Objective The purpose of this study was to determine whether clinical, health‐related quality of life (HRQL), and gait characteristics in adults with knee osteoarthritis (OA) differed by obesity category. Methods This cross‐sectional analysis of 823 older adults (mean age 64.6 years, SD 7.8 years) with knee OA and overweight or obesity compared clinical, HRQL, and gait outcomes among obesity classifications (overweight or class I, body mass index [BMI] 27.0–34.9; class II, BMI 35.0–39.9; class III BMI ≥40.0). Results Patients with class III obesity had worse Western Ontario McMasters Universities Arthritis Index knee pain (0–20) than the overweight or class I (mean 8.6 vs 7.0; difference 1.5; 95% confidence interval [CI] 1.0–2.1; P < 0.0001) and class II (mean 8.6 vs 7.4; difference 1.1; 95% CI 0.6–1.7; P = 0.0002) obesity groups. The Short Form 36 physical HRQL measure was lower in the class III obesity group compared to the overweight or class I (mean 31.0 vs 37.3; difference −6.2; 95% CI −7.8 to −4.7; P < 0.0001) and class II (mean 31.0 vs 35.0; difference −3.9; 95% CI −5.6 to −2.2; P < 0.0001) obesity groups. The class III obesity group had a base of support (cm) during gait that was wider than that for the overweight or class I (mean 14.0 vs 11.6; difference 3.3; 95% CI 2.6–4.0; P < 0.0001) and class II (mean 14.0 vs 11.6; difference 2.4; 95% CI 1.6–3.2; P < 0.0001) obesity groups. Conclusion Among adults with knee OA, those with class III obesity had significantly higher pain levels and worse physical HRQL and gait characteristics compared to adults with overweight or class I or class II obesity. image

Aims:To determine whether discrete lipid profiles (refer to as lipid phenotyping) can be used to stratify cardiovascular risk in individuals with type 2 diabetes. Methods and results:Cardiovascular Health Study participants with diabetes and fasting lipid profiles at baseline (n = 866) were categorized separately by level of LDL cholesterol and HDL-C/Triglyceride (Tg) profiles (low Tg/high HDL-C; high Tg/low HDL-C; high Tg only or low HDL-C only). We performed Cox multivariate regression analysis to assess the risk of CVD mortality, incident myocardial infarction (MI), heart failure (HF), stroke, and composite MACE (MI, HF, stroke, and CVD mortality) associated with each lipid category. We also calculated risk estimates for MACE using lipid measures as continuous variables. In the fully adjusted model, the high triglyceride plus low HDL-C cholesterol phenotype demonstrated risk that was at least as high as the highest LDL-C sub-group phenotype for CVD mortality (Hazard ratio {HR} 1.58 vs 1.48), MI (HR 1.53 vs 1.58), HF (HR 1.47 vs 1.20), stroke (HR 2.02 vs 1.43), and MACE (HR 1.58 vs 1.38). When modeled continuously, the HR per SD for MACE was 1.12 (p = 0.03) for LDL-C and 1.19-1.20 (p < 0.001) for triglycerides or remnant cholesterol. Conclusions:Participants with the high triglyceride/low HDL-C phenotype had equivalent or higher CVD risk than those with the high LDL-C phenotype. Further studies are necessary to determine whether lipid phenotyping accounts for the substantial CVD risk not explained by LDL cholesterol among individuals with type 2 diabetes.

Biopsies of muscle and adipose tissue (AT) are useful tools to gain insights into the aging processes in these tissues. However, they are invasive procedures and their risk/benefit profile in older adults can be altered by sarcopenia, frailty, poor healing, and multimorbidity. Their success rates, safety, and tolerability in a geriatric population have not been reported in detail. Investigators in the Study of Muscle, Mobility, and Aging (SOMMA) performed biopsies of muscle and AT in older adults and prospectively collected data on biopsy success rates, safety, and tolerability. We report here the methods and outcomes of these two procedures. In total, 861 participants (aged 70-94) underwent percutaneous biopsies of the Vastus lateralis muscle with a Bergstrom needle. A subset (n=241) also underwent percutaneous biopsies of the abdominal subcutaneous AT with the tumescent liposuction technique. Success rate was assessed by the percentage of biopsies yielding adequate specimens for analyses; tolerability by pain scores; and safety by frequency of adverse events. All data were prospectively collected. The overall muscle biopsy success rate was 97.1% and was modestly lower in women. The AT biopsy success rate was 95.9% and slightly lower in men. Minimal or no pain was reported in 68% of muscle biopsies and in 83% of AT biopsies. Adverse events occurred in 2.67% of muscle biopsies and 4.15% of AT biopsies. None was serious. In older adults, percutaneous muscle biopsies and abdominal subcutaneous AT biopsies have an excellent safety profile, often achieve adequate tissue yields for analyses, and are well tolerated.

Purpose: Knee osteoarthritis (OA) is a prevalent, debilitating, and costly condition that is exacerbated by excess body weight. The Weight Loss and Exercise for Communities with Arthritis in North Carolina (WE-CAN) trial tested both community-based Health Education (HE) and Diet and Exercise (D+E) interventions. HE consisted of periodic group meetings focused on nutrition and other health literacy topics. D+E consisted of a calorie-restricted dietary plan and group exercise sessions delivered in community settings by trained exercise interventionists.

Importance Some weight loss and exercise programs that have been successful in academic center-based trials have not been evaluated in community settings. Objective To determine whether adaptation of a diet and exercise intervention to community settings resulted in a statistically significant reduction in pain, compared with an attention control group, at 18-month follow-up. Design, Setting, and Participants Assessor-blinded randomized clinical trial conducted in community settings in urban and rural counties in North Carolina. Patients were men and women aged 50 years or older with knee osteoarthritis and overweight or obesity (body mass index ≥27). Enrollment (N = 823) occurred between May 2016 and August 2019, with follow-up ending in April 2021. Interventions Patients were randomly assigned to either a diet and exercise intervention (n = 414) or an attention control (n = 409) group for 18 months. Main Outcomes and Measures The primary outcome was the between-group difference in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) knee pain score (range, 0 [none] to 20 [severe]; minimum clinically important difference, 1.6) over 18 months, tested using a repeated-measures mixed linear model with adjustments for covariates. There were 7 secondary outcomes including body weight. Results Among the 823 randomized patients (mean age, 64.6 years; 637 [77%] women), 658 (80%) completed the trial. At 18-month follow-up, the adjusted mean WOMAC pain score was 5.0 in the diet and exercise group (n = 329) compared with 5.5 in the attention control group (n = 316) (adjusted difference, -0.6; 95% CI, -1.0 to -0.1; P = .02). Of 7 secondary outcomes, 5 were significantly better in the intervention group compared with control. The mean change in unadjusted 18-month body weight for patients with available data was -7.7 kg (8%) in the diet and exercise group (n = 289) and -1.7 kg (2%) in the attention control group (n = 273) (mean difference, -6.0 kg; 95% CI, -7.3 kg to -4.7 kg). There were 169 serious adverse events; none were definitely related to the study. There were 729 adverse events; 32 (4%) were definitely related to the study, including 10 body injuries (9 in diet and exercise; 1 in attention control), 7 muscle strains (6 in diet and exercise; 1 in attention control), and 6 trip/fall events (all 6 in diet and exercise). Conclusions and Relevance Among patients with knee osteoarthritis and overweight or obesity, diet and exercise compared with an attention control led to a statistically significant but small difference in knee pain over 18 months. The magnitude of the difference in pain between groups is of uncertain clinical importance. Trial Registration ClinicalTrials.gov Identifier: NCT02577549.

To determine whether long-term diet (D) and exercise (E) interventions, alone or in combination (D+E), have beneficial effects for older adults with knee osteoarthritis (OA) 3.5 years after the interventions end. This is a secondary analysis of a subset (n = 94) of the first 184 participants who had successfully completed the Intensive Diet and Exercise in Arthritis (IDEA) trial (n = 399) and who consented to follow-up testing. Participants were older (age ≥55 years), overweight, and obese adults with radiographic and symptomatic knee OA in at least 1 knee who completed 1.5-year D+E (n = 27), D (n = 35), or E (n = 32) interventions and returned for 5-year follow-up testing an average of 3.5 years later. During the 3.5-years following the interventions, weight regain in D+E and D was 5.9 kg (7%) and 3.1 kg (4%), respectively, with a 1-kg (1%) weight loss in E. Compared to baseline, weight (D+E –3.7 kg [ P  = 0.0007], D –5.8 kg [ P  < 0.0001], E –2.9 kg [ P  = 0.003]) and Western Ontario and McMaster Universities Osteoarthritis Index pain subscale scores (D+E –1.2 [ P  = 0.03], D –1.5 [ P  = 0.001], E –1.6 [ P  = 0.0008]) were lower in each group at the 5-year follow-up. The effect of group assignment at the 5-year follow-up was significant for body weight, with D being less than E (–3.5 kg; P  = 0.04). Older adults with knee OA who completed 1.5-year D or D+E interventions experienced partial weight regain 3.5 years later; yet, relative to baseline, they preserved statistically significant changes in weight loss and reductions in knee pain.

OBJECTIVE To determine whether long-term diet (D) and exercise (E) interventions, alone or in combination (D+E), have beneficial effects for older adults with knee osteoarthritis 3.5-years after the interventions end. METHODS This is a secondary analysis of a subset (N = 94) of the first 184 participants who had successfully completed the Intensive Diet and Exercise in Arthritis (IDEA) trial (N = 399) and who consented to follow-up testing. Participants were older (age ≥ 55 years), overweight and obese adults with radiographic and symptomatic knee osteoarthritis in at least one knee who completed 1.5-year D+E (N=27), D (N=35), or E (N=32) interventions and returned for 5-year follow-up testing an average of 3.5-years later. RESULTS During the 3.5-years following the interventions, weight regain in D+E and D was 5.9 kg (7%) and 3.1 kg (4%), respectively, with a 1 kg (1%) weight loss in E. Compared to baseline, weight (D+E, -3.7 kg, P=.0007; D, -5.8 kg, P<.0001; E, -2.9 kg, P=.003) and WOMAC pain (D+E, -1.2, P=.03; D, -1.5, P=.001; E -1.6, P=.0008) were lower in each group at 5-year follow-up. The effect of group assignment at 5-year follow-up was significant for body weight, with D less than E (-3.5 kg, P=.04). DISCUSSION Older adults with knee osteoarthritis who completed 1.5-year diet or diet plus exercise interventions experienced partial weight regain 3.5 years later, yet relative to baseline, they preserved statistically significant changes in weight loss and reductions in knee pain.

Heart failure (HF) and myocardial infarction are serious complications of major noncardiac surgery in older adults. Many factors can contribute to the development of HF during the postoperative period. The incidence of, and risk factors for, procedure-associated heart failure (PHF) occurring at the time of, or shortly after, medical procedures in a population-based sample >= 65 years of age have not been fully characterized, particularly in comparison with HF not proximate to medical procedures. This analysis comprises 5,121 men and women free of HF at baseline from the Cardiovascular Health Study who were followed up for 12.0 years (median). HF events were documented by self-report at semiannual contacts and confirmed by a formal adjudication committee using a review of the participants' medical records and standardized criteria for HF. Incident HF events were additionally adjudicated as either being related or unrelated to a medical procedure (PHF and non-PHF, respectively). We estimated cause-specific hazards ratios for the association of covariates with PHF and non-PHF. There were 1,728 incident HF events in the primary analysis: 168 (10%) classified as PHF, 1,526 (88%) as non-PHF, and 34 unclassified (2%). For those 1,045 participants in whom LV ejection fraction was known at the time of the HF event, it was >45% in 89 of 118 participants (75%) with PHF, compared to 517 of 927 participants (55%) with non-PHF (p < 0.001). Increased age, male gender, diabetes, and angina at baseline were associated with both PHF and non-PHF (range of hazard ratios (HR): 1.04-2.05]. Being Black was inversely associated with PHF [HR: 0.46, 95% confidence interval: 0.25-0.86]. Participants with increased age, without baseline angina, and with baseline LVEF<55% were at a significantly lower risk for PHF compared to nonPHF. Among those with PHF, surgical procedures-including cardiac, orthopedic, gastrointestinal, vascular, and urologic-comprised 83.3%, while percutaneous procedures comprised 8.9% (including 6.5% represented by cardiac catheterizations and pacemaker placements). Another group composed of a variety of procedures commonly requiring large fluid volume administration comprised 7.7%. There was a lower all-cause 30-day mortality in the PHF versus the non-PHF group (2.2% vs 5.7%), with a nonsignificant odds ratio of 0.39 in a minimally adjusted model. When individuals with prior myocardial infarction (MI) were excluded in a sensitivity analysis, the proportion of incident HF with concurrent MI was greater for PHF (32.9%) than for non-PHF (19.8%). In conclusion, PHF in older adults is a common entity with relatively low 30-day mortality. Baseline angina, lower age, and LVEF >= 55% were associated with a higher risk of PHF compared to non-PHF. Being Black was associated with a lower risk of PHF and PHF as a proportion of HF was lower in Black than in non-Black participants. Compared to non-PHF, PHF more frequently presented with concurrent MI and with preserved LV ejection fraction. (C) 2021 Elsevier Inc. All rights reserved.

Purpose Loss of muscle mass and strength are associated with long-term adverse health outcomes in older adults. Urine creatinine concentrations (Ucr; mg/dl) are a measure of muscle tissue mass and turnover. This study assessed the associations of a spot Ucr level with muscle mass and with risk of hospitalization, mortality, and diabetes mellitus in older adults. Methods We examined 3424 participants from the Cardiovascular Health Study who provided spot urine samples in 1996-1997 and who were followed through June 2015. All participants underwent baseline measurement of grip strength. In a sub-cohort, 1331 participants underwent dual energy X-ray absorptiometry (DEXA) scans, from which lean muscle mass was derived. Participants were followed for a median of 10 years for hospitalizations and mortality, and 9 years for diabetes mellitus. Results In linear regression analysis, a one standard deviation higher Ucr concentration (64.6 mg/dl) was associated with greater grip strength (kg force) beta = 0.44 [0.16, 0.72]; p = 0.002) and higher lean muscle mass (kg) (beta = 0.43 [0.08, 0.78]; p = 0.02). In Cox regression analyses, each standard deviation greater Ucr concentration was associated with lower rates of hospitalizations (0.94 [95% confidence interval, 0.90, 0.98]; p < 0.001) and lower mortality risk (0.92 [0.88, 0.97]; p < 0.001), while a one standard deviation increase in muscle mass derived from DEXA had no such significant association. Ucr levels were not associated with incident diabetes mellitus risk (0.97 [0.85, 1.11]; p = 0.65). Conclusion A higher spot Ucr concentration was favorably associated with muscle mass and strength and with health outcomes in older community-living adults. The ease of obtaining a spot Ucr makes it an attractive analyte to use for gauging the health of older adults.

Objective To determine whether long-term diet (D) and exercise (E) interventions, alone or in combination (D+E), have beneficial effects for older adults with knee osteoarthritis (OA) 3.5 years after the interventions end. Methods This is a secondary analysis of a subset (n = 94) of the first 184 participants who had successfully completed the Intensive Diet and Exercise in Arthritis (IDEA) trial (n = 399) and who consented to follow-up testing. Participants were older (age >= 55 years), overweight, and obese adults with radiographic and symptomatic knee OA in at least 1 knee who completed 1.5-year D+E (n = 27), D (n = 35), or E (n = 32) interventions and returned for 5-year follow-up testing an average of 3.5 years later. Results During the 3.5-years following the interventions, weight regain in D+E and D was 5.9 kg (7%) and 3.1 kg (4%), respectively, with a 1-kg (1%) weight loss in E. Compared to baseline, weight (D+E -3.7 kg [P = 0.0007], D -5.8 kg [P < 0.0001], E -2.9 kg [P = 0.003]) and Western Ontario and McMaster Universities Osteoarthritis Index pain subscale scores (D+E -1.2 [P = 0.03], D -1.5 [P = 0.001], E -1.6 [P = 0.0008]) were lower in each group at the 5-year follow-up. The effect of group assignment at the 5-year follow-up was significant for body weight, with D being less than E (-3.5 kg; P = 0.04). Conclusion Older adults with knee OA who completed 1.5-year D or D+E interventions experienced partial weight regain 3.5 years later; yet, relative to baseline, they preserved statistically significant changes in weight loss and reductions in knee pain.

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Background FABP‐4 (fatty acid binding protein‐4) is a lipid chaperone in adipocytes and has been associated with prognosis in selected clinical populations. We investigated the associations between circulating FABP‐4, risk of incident cardiovascular disease (CVD), and risk of CVD mortality among older adults with and without established CVD. Methods and Results In the Cardiovascular Health Study, we measured FABP4 levels in stored specimens from the 1992–993 visit and followed participants for incident CVD if they were free of prevalent CVD at baseline and for CVD mortality through June 2015. We used Cox regression to estimate hazard ratios for incident CVD and CVD mortality per doubling in serum FABP‐4 adjusted for age, sex, race, field center, waist circumference, blood pressure, lipids, fasting glucose, and C‐reactive protein. Among 4026 participants free of CVD and 681 with prevalent CVD, we documented 1878 cases of incident CVD and 331 CVD deaths, respectively. In adjusted analyses, FABP‐4 was modestly associated with risk of incident CVD (mean, 34.24; SD, 18.90; HR, 1.10 per doubling in FABP‐4, 95% CI, 1.00–1.21). In contrast, FABP‐4 was more clearly associated with risk of CVD mortality among participants without (HR hazard ratio 1.24, 95% CI, 1.10–1.40) or with prevalent CVD (HR hazard ratio 1.57, 95% CI, 1.24–1.98). These associations were not significantly modified by sex, age, and waist circumference. Conclusions Serum FABP‐4 is modestly associated with risk of incident CVD even after adjustment for standard risk factors, but more strongly associated with CVD mortality among older adults with and without established CVD.

Purpose: Few have studied long-term strength training in knee osteoarthritis (OA) patients due to the unsubstantiated belief that it might exacerbate OA symptoms. The purpose of this secondary analysis was to determine whether knee OA patients with low-baseline knee strength would benefit more from 18-months of strength training compared to patients with high-baseline knee strength. Methods: START was a single-blind, 18-month, 3-arm randomized clinical trial conducted between September 2011 and August 2017. Participants were 377 community-dwelling adults (age ≥ 55 years) with a body mass index of 20-45 kg/m2 (mean = 31.4 kg/m2) with pain and mild to moderate radiographic knee OA (KLG = 2 or 3). Randomization was to either high-intensity (HI) strength training (75-90% 1RM), low-intensity (LI) strength training (30-40% 1RM), or attention control (C). The lowest 50% of participants in each group based on knee extensor strength (N = 186) were compared on clinical (e.g., pain, function), structural (e.g., joint space width), and mechanistic (e.g., inflammatory biomarkers) measures at 18-month follow-up (FU18) to participants with the highest 50% of baseline knee strength (N = 185). All statistical analyses used an intention-to-treat method with significant effects (high-baseline strength vs. low-baseline strength) set at p= 0.05. Results: In participants with low-baseline knee extensor strength, mean knee extension and flexion strength improved an average of 75%, and hip abductor strength improved an average of 20% at FU18 in the two strength training intensity groups (LI, HI), compared to 41% and 13% improvements in strength, respectively in the C group. However, in the high-baseline knee strength cohort, changes in knee and hip strength for the two strength training groups were 3% and -8%, and -8% and -4% for the C group. The increases in strength in the low-baseline strength training groups combined with the lack of strength increases in the high-base strength groups resulted in non-significant differences at FU18 in strength between the low-baseline and high-baseline strength cohorts (Table 1). Pain (p =0.40), function (p =0.34), 6-minute walk distance (p=0.45), joint space width (p=0.58), thigh muscle volume (p=0.58), IL-6 (p=0.38), and knee compressive force (p=0.43) were not significantly different between the high-baseline and low-baseline strength cohorts at FU18.Tabled 1Table 1. Mean (95%CI) strength for low and high baseline strength groupsStrength TestC-hi baseline strengthLI-hi baseline strengthHI-hi baseline strengthC-low baseline strengthLI-low baseline strengthHI-low baseline strengthP-hi vs low baseline strengthKnee Extension (N)84.3 (77.9,90.6)92.1 (86.3,97.8)96.1 (90.1,102.1)84.2 (78.0,90.4)90.7 (84.6,96.8)95.5 (89.7,101.3)0.98Knee Flexion (N)44.1 (40.3,47.9)50.1 (46.5,53.7)51.5 (47.8,55.3)41.1 (37.3,45.0)50.3 (46.6,54.1)49.4 (45.8,53.0)0.67Hip Abduction (N)68.9 (64.7,73.0)73.4 (69.4,77.4)70.7 (66.7,74.7)65.3 (61.1,69.5)73.4 (69.3,77.5)73.0 (69.1,77.0)0.36 Open table in a new tab Conclusions: We recently reported that analysis of the START cohort revealed significantly greater improvements in strength in the LI and HI groups versus C, with clinically important reductions in pain and improvements in function in all three groups (LI, HI, C) at FU18 with no significant difference between them. The current analysis revealed that gains in strength occurred predominately in the low-baseline strength cohort, and included the C as well as the LI and HI strength training groups. Although there were no strength gains in the high-baseline strength cohort, this cohort had similar 18-month follow-up clinical, structural, and mechanistic values as the low-baseline strength cohort that made significant strength gains. Participation in the clinical trial, independent of group assignment and baseline knee strength, appears at least partially responsible for the similar outcomes. Trial Registration: NCT01489462

Acid-base balance affects muscle quality in older adults leading to less muscle mass and strength. Individuals with knee osteoarthritis (OA) have less muscle mass and strength. It is unknown if OA’s effect on function and strength is mediated by acid-base balance. PURPOSE: This study examined associations between dietary acid production, physical function, muscle strength, and body composition in older obese adults with knee osteoarthritis. Higher acid load is hypothesized to be associated with lower physical function, strength and lean body mass (LBM). METHODS: Baseline data from the Intensive Diet and Exercise for Arthritis (IDEA) trial were used for this analysis. Measurements from IDEA included a 3-day food record to calculate daily potential renal acid load (PRAL)PRAL, 6-min walk distance, LBM via dual energy x-ray absorptiometry, and concentric knee extensor and flexor strength. Estimated potential renal acid load (PRAL in mEq H+ ions) = (0.49*mg protein) + (.037*mg phosphorus) - (.021*mg potassium) - (.026*mg magnesium) - (.013*mg calcium). Associations were determined by Pearson correlations. RESULTS: Data obtained from 388 participants (age=65.8±6.1 yrs; 70.4% female; body mass index=33.7±3.8 kg/m2) were used in the analysis. Mean values were: PRAL score (8.9±13.8 mEq/d); LBM (56.0±12.0 kg); 6-min walk distance (476.5±82.6 m); concentric knee extensor (60.2±26.0 Nm) and knee flexor (30.2±14.7 Nm) strength. PRAL showed significant positive associations with concentric knee extensor strength (r=.19; p=.011), knee flexor strength (r=.19; p=.012), and LBM (r=.22, p<.001). CONCLUSION: The physiological importance of the statistical relationship observed for high PRAL (higher acid load) and high physical function and knee extensor and flexor strength, although minimal (r~.2), opposes our hypothesis. These discrepant findings may be from using an indirect measure acid production, presence of OA in this cohort, and the accuracy of self-reported dietary records.

The Intensive Diet and Exercise for Arthritis (IDEA) trial was an 18-month randomized controlled trial that enrolled 454 overweight and obese older adults with symptomatic and radiographic knee osteoarthritis (OA). Participants were randomized to either exercise (E), intensive diet-induced weight loss (D), or intensive diet-induced weight loss plus exercise (D + E) interventions. We previously reported that the clinical benefits of D + E were significantly greater than with either intervention alone (e.g., greater pain reduction, and better function, mobility, and health-related quality of life). We now test the hypothesis that D + E has greater overall benefit on gait mechanics compared to either intervention alone. Knee joint loading was analyzed using inverse dynamics and musculoskeletal modeling. Analysis of covariance determined the interventions’ effects on gait. The D + E group walked significantly faster at 18-month follow-up (1.35 m s−1) than E (1.29 m s−1, p = 0.0004) and D (1.31 m s−1, p = 0.0007). Tibiofemoral compressive impulse was significantly lower (p = 0.0007) in D (1069 N s) and D + E (1054 N s) compared to E (1130 N s). D had significantly lower peak hip external rotation moment (p = 0.01), hip abduction moment (p = 0.0003), and peak hip power production (p = 0.016) compared with E. Peak ankle plantar flexion moment was significantly less (p < 0.0001) in the two diet groups compared with E. There also was a significant dose-response to weight loss; participants that lost >10% of baseline body weight had significantly (p = 0.0001) lower resultant knee forces and lower muscle (quadriceps, hamstring, and gastrocnemius) forces than participants that had less weight loss. Compared to E, D produces significant load reductions at the hip, knee, and ankle; combining D with E attenuates these reductions, but most remain significantly better than with E alone.

Objective This study examined the short‐ and long‐term effects of adding caloric restriction to 5 months of aerobic exercise training on executive function in sedentary older adults with obesity. Methods Sedentary adults with obesity aged 65 to 79 years completed a randomized trial investigating the cardiorespiratory benefits of adding moderate (~ 250 kcal) or high (~ 600 kcal) caloric restriction to a 20‐week aerobic exercise program. Approximately half ( n = 88) completed a cognitive assessment battery at baseline, post intervention, and 18 to 24 months after intervention completion. The primary outcome was an executive function composite score. Results In the overall sample, the executive function composite increased 0.114 from baseline to postintervention ( P = 0.01). Randomization to caloric restriction did not significantly alter executive function over aerobic exercise alone, nor were there between‐group differences on any individual executive function test following the intervention or at long‐term follow‐up. Adding caloric restriction to exercise was associated with a modest increase in Mini‐Mental State Examination score ( P = 0.04). In the overall sample, increases from baseline at long‐term follow‐up were noted in digit symbol and word list recall performance as well. Conclusions Adding caloric restriction to a 20‐week aerobic exercise program does not worsen or improve executive function more than exercise alone assessed up to 24 months post randomization.

BACKGROUNDObesity compounds aging-related declines in cardiorespiratory fitness, with accompanying fatigue and disability. This study determined the effects of two different levels of caloric restriction (CR) during aerobic training on cardiorespiratory fitness, fatigue, physical function, and cardiometabolic risk.METHODSThe INFINITE study was a 20-week randomized trial in 180 older (65-79 years) men and women with obesity (body mass index = 30-45 kg/m2). Participants were randomly assigned to (i) aerobic training (EX; treadmill 4 days/wk for 30 minutes at 65%-70% of heart rate reserve), (ii) EX with moderate (-250 kcal/d) CR (EX + Mod-CR), or (iii) EX with more intensive (-600 kcal/d) CR (EX + High-CR). Cardiorespiratory fitness (peak aerobic capacity, VO2 peak, primary outcome) was determined during a graded exercise test.RESULTSOne hundred and fifty-five participants returned for 20-week data collection (87% retention). VO2 peak increased by 7.7% with EX, by 13.8% with EX + Mod-CR, and by 16.0% with EX + High-CR, and there was a significant treatment effect (EX + High-CR = 21.5 mL/kg/min, 95% confidence interval = 19.8-23.2; EX + Mod-CR = 21.2 mL/kg/min, 95% confidence interval = 19.4-23.0; EX = 20.1 mL/kg/min, 95% confidence interval = 18.4-21.9). Both CR groups exhibited significantly greater improvement in self-reported fatigue and disability and in glucose control, compared with EX.CONCLUSIONCombining aerobic exercise with even moderate CR is more efficacious for improving cardiorespiratory fitness, fatigue and disability, and glucose control than exercise alone and is as effective as higher-dose CR.