Objective
Obesity exacerbates pain and functional limitation in persons with knee osteoarthritis (OA). In the Weight Loss and Exercise for Communities with Arthritis in North Carolina (WE‐CAN) study, ...a community‐based diet and exercise (D + E) intervention led to an additional 6 kg weight loss and 20% greater pain relief in persons with knee OA and body mass index (BMI) >27 kg/m2 relative to a group‐based health education (HE) intervention. We sought to determine the incremental cost‐effectiveness of the usual care (UC), UC + HE, and UC + (D + E) programs, comparing each strategy with the “next‐best” strategy ranked by increasing lifetime cost.
Methods
We used the Osteoarthritis Policy Model to project long‐term clinical and economic benefits of the WE‐CAN interventions. We considered three strategies: UC, UC + HE, and UC + (D + E). We derived cohort characteristics, weight, and pain reduction from the WE‐CAN trial. Our outcomes included quality‐adjusted life years (QALYs), cost, and incremental cost‐effectiveness ratios (ICERs).
Results
In a cohort with mean age 65 years, BMI 37 kg/m2, and Western Ontario and McMaster Universities Osteoarthritis Index pain score 38 (scale 0–100, 100 = worst), UC leads to 9.36 QALYs/person, compared with 9.44 QALYs for UC + HE and 9.49 QALYS for UC + (D + E). The corresponding lifetime costs are $147,102, $148,139, and $151,478. From the societal perspective, UC + HE leads to an ICER of $12,700/QALY; adding D + E to UC leads to an ICER of $61,700/QALY.
Conclusion
The community‐based D + E program for persons with knee OA and BMI >27kg/m2 could be cost‐effective for willingness‐to‐pay thresholds greater than $62,000/QALY. These findings suggest that incorporation of community‐based D + E programs into OA care may be beneficial for public health.
The infrapatellar fat pad (IPFP) represents intra-articular adipose tissue that may contribute to intra-articular inflammation and pain by secretion of proinflammatory cytokines. Here we examined the ...impact of weight loss by diet and/or exercise interventions on the IPFP volume.
Intensive Diet and Exercise for Arthritis (IDEA) was a single-blinded, single-center, 18-month, prospective, randomized controlled trial that enrolled 454 overweight and obese older adults with knee pain and radiographic osteoarthritis. Participants were randomized to 1 of 3 groups: exercise-only control (E), diet-induced weight loss (D), and diet-induced weight loss + exercise (D+E). In a subsample (n = 106; E: n = 36, D: n = 35, and D+E: n = 35), magnetic resonance images were acquired at baseline and at the 18-month follow-up, from which we analyzed IPFP volume, surface areas, and thickness in this secondary analysis.
The average weight loss amounted to 1.0% in the E group, 10.5% in the D group, and 13.0% in the D+E group. A significant (p < 0.01) reduction in IPFP volume was observed in the E (2.1%), D (4.0%), and D+E (5.2%) groups. The IPFP volume loss in the D+E group was significantly greater than that in the E group (p < 0.05) when not adjusting for parallel comparisons. Across intervention groups, there were significant correlations between IPFP volume change, individual weight loss (r = 0.40), and change in total body fat mass (dual-energy X-ray absorptiometry; r = 0.44, n = 88) and in subcutaneous thigh fat area (computed tomography; r = 0.32, n = 82).
As a potential link between obesity and knee osteoarthritis, the IPFP was sensitive to intervention by diet and/or exercise, and its reduction was correlated with changes in weight and body fat.
Determine the safety and initial efficacy of a novel biofeedback intervention to improve landing mechanics in patients following anterior cruciate ligament reconstruction (ACLR).
Forty patients ...post-ACLR (age: 16.9 ± 2.0 years) were randomly allocated to a biofeedback intervention or an attention control group. Patients in the biofeedback group completed 12 sessions over six-weeks that included bilateral unweighted squats with visual and tactile biofeedback. Patients in the control group completed a six-week educational program. Lower extremity mechanics were collected during a bilateral stop jump at baseline, six-weeks, and 12-weeks post-intervention. Linear mixed-effects models adjusted for sex and graft type determined the main effects of and interactions between group and time.
No group by time interaction existed for peak knee extension moment symmetry. A group by time interaction existed for peak vertical ground reaction force symmetry (p = 0.012), where patients in the biofeedback group had greater improvements in symmetry between baseline and post-intervention that were not maintained through the retention assessments.
This novel biofeedback program did not reduce risk factors for second ACL injuries. Future work could develop and test multidisciplinary interventions for reducing second ACL injury risk factors.
(NCT03273673)
•Squat biofeedback can improve loading symmetry in landing.•Squat biofeedback does not improve knee extension moment symmetry in landing.•Squat biofeedback is not sufficient to decrease 2nd ACL injury risk factors.•Combined mental and physical interventions need to be explored.
Objective: Physical function and body composition in older obese adults with knee osteoarthritis (OA) were examined after intensive weight loss.
Research Methods and Procedures: Older obese adults (n ...= 87; ≥60 years; BMI ≥ 30.0 kg/m2) with symptomatic knee OA and difficulty with daily activities were recruited for a 6‐month trial. Participants were randomized into either a weight stable (WS) or weight loss (WL) program. Participants in WL (10% weight loss goal) were prescribed a 1000 kcal/d energy deficit diet with exercise 3 d/wk. WS participants attended health information sessions. Body composition and physical function (Western Ontario and McMaster University Osteoarthritis Index, 6‐minute walking distance, and stair climb time) were assessed at baseline and 6 months. Statistical analysis included univariate analysis of covariance on 6‐month measurements using baseline values as covariates. Associations between physical function and body composition were performed.
Results: Body weight decreased 8.7 ± 0.8% in WL and 0.0 ± 0.7% in WS. Body fat and fat‐free mass were lower for WL than WS at 6 months (estimated means: fat = 38.1 ± 0.4% vs. 40.9 ± 0.4%, respectively; fat‐free mass = 56.7 ± 0.4 vs. 58.8 ± 0.4 kg, respectively). WL had better function than WS, with lower Western Ontario and McMaster University Osteoarthritis Index scores, greater 6‐minute walk distance, and faster stair climb time (p < 0.05). Changes in function were associated with weight loss in the entire cohort.
Discussion: An intensive weight loss intervention incorporating energy deficit diet and exercise training improves physical function in older obese adults with knee OA. Greater improvements in function were observed in those with the most weight loss.
The mechanisms by which obesity affects osteoarthritis (OA) are of great concern to osteoarthritis researchers and clinicians who manage this disease. Inflammation and joint loads are pathways ...commonly believed to cause or to exacerbate the disease process. This article reviews the physiologic and mechanical consequences of obesity in older adults who have knee OA, the effects of long-term exercise and weight-loss interventions, the most effective nonpharmacologic treatments for obesity, and the usefulness and feasibility of translating these results to clinical practice.
The Walk With Ease (WWE) program was developed by the Arthritis Foundation to help people with arthritis learn to exercise safely and improve arthritis symptoms. We sought to establish the value of ...the WWE program.
We used the Osteoarthritis Policy (OAPol) Model, a widely published and validated computer simulation of knee osteoarthritis (OA), to assess the cost-effectiveness of WWE in knee OA. We derived model inputs using data from a workplace wellness initiative in Montana that offered WWE to state employees. Our primary outcomes were quality-adjusted life years (QALYs) and costs over a 2-year period, which we used to calculate the incremental cost-effectiveness ratio (ICER). The base case analysis was restricted to subjects who were inactive or insufficiently active (<180 min/week of PA) at baseline. We performed scenario and probabilistic sensitivity analyses to determine the impact of uncertainty in model parameters on our results.
In the base case analysis, adding WWE to usual care resulted in an ICER of $47,900/QALY. When the program was offered without preselection by baseline activity level, the ICER for WWE + usual care was estimated at $83,400/QALY. Results of the probabilistic sensitivity analysis indicated that WWE offered to inactive or insufficiently active individuals has a 52% chance of having an ICER <$50,000/QALY.
The WWE program offers good value for inactive/insufficiently active individuals. Payers may consider including such a program to increase physical activity in individuals with knee OA.
Predicting biotic responses to environmental change requires understanding the joint effects of abiotic conditions and biotic interactions on community dynamics. One major challenge is to separate ...the potentially confounding effects of abiotic environmental variation and local biotic interactions on individual performance. The stress gradient hypothesis (SGH) addresses this issue directly by predicting that the effects of biotic interactions on performance become more positive as the abiotic environment becomes more stressful. It is unclear, however, how the predictions of the SGH apply to plants of differing functional strategies in diverse communities. We asked (1) how the effect of crowding on performance (growth and survival) of trees varies across a precipitation gradient, and (2) how functional strategies (as measured by two key traits: wood density and leaf mass per area, LMA) mediate average demographic rates and responses to crowding across the gradient. We built trait-based neighborhood models of growth and survival across a regional precipitation gradient where increasing precipitation is associated with reduced abiotic stress. In total, our dataset comprised ∼170,000 individual trees belonging to 252 species. The effect of crowding on tree performance varied across the gradient; crowding negatively affected growth across plots and positively affected survival in the wettest plot. Functional traits mediated average demographic rates across the gradient, but we did not find clear evidence that the strength of these responses depends on species’ traits. Our study lends support to the SGH and demonstrates how a trait-based perspective can advance these concepts by linking the diversity of species interactions with functional variation across abiotic gradients.
Aquatic exercise is recommended by the Osteoarthritis Research Society (OARSI), by the American College of Rheumatology (ACR) and by the European League Against Rheumatism (EULAR) as a ...nonpharmacological method of controlling the knee osteoarthritis (KOA) symptoms. Moreover, given that weight loss results in a reduction of the load that is exerted upon the knee during daily activities, obesity is also considered to be a modifiable risk factor for the development and or exacerbation of KOA. The implementation of an exercise based weight loss program may, however, itself be limited by the symptoms of KOA. The aquatic program against osteoarthritis (termed "PICO" in Portuguese) prioritizes the control of symptoms and the recovery of functionality, with an attendant increase in the patient's physical activity level and, consequently, metabolic rate. Our laboratory is assessing the effectiveness of 3 months of PICO on the symptoms of KOA, on physical function, on quality of life and on gait. In addition, PICO shall examine the effects of said exercise intervention on inflammatory biomarkers, psychological health, life style and body composition.
The trial is a prospective, single-blinded, randomized controlled trial, and involves 50 overweight and obese adults (BMI = 28-43.5 kg/m²; age 40-65 yrs) with radiographic KOA. The participants are randomly allocated into either an educational attention (control) group or an aquatic (exercise program) group. This paper describes the experimental protocol that is used in the PICO project.
The PICO program shall provide insight into the effectiveness of an aquatic exercise program in the control of KOA symptoms and in the improvement of the quality of life. As such, they are likely to prove a useful reference to health professionals who intend to implement any kind of therapeutic intervention based around aquatic exercise.
NCT01832545.
Background. Although weight loss reduces risk for comorbid diseases, many observational studies suggest that weight loss is associated with increased mortality risk, leading to reluctance by ...clinicians to consider weight reduction as a strategy to maintain health and independence in older adults. However, whether the observed weight loss is intentional is difficult to determine and may not accurately represent the mortality risk associated with intentional weight reduction. Data from the Arthritis, Diet, and Activity Promotion Trial (ADAPT) were used to determine whether randomization to a weight reduction program was associated with total mortality in overweight/obese older adults. Methods. ADAPT (n = 318; mean age 69 ± 6 years, body mass index 34 ± 5 kg/m2, 72% female) assessed the influence of weight loss (achieved through dietary counseling and lifestyle modification) and/or exercise on function in overweight/obese older adults with knee osteoarthritis. ADAPT ended in December 1999. Participant vital was ascertained status through December 2006 using the National Death and Social Security Indexes. Results. The mortality rate for those randomized to the 18-month weight loss intervention (n = 159, mean weight loss = −4.8 kg, 15 deaths) was lower than that for those not randomized to the weight loss intervention (n = 159, mean weight loss = −1.4 kg, 30 deaths; hazard rate ratio = 0.5, 95% confidence interval 0.3–1.0). Results were not appreciably changed when analyses were stratified by age, gender, baseline weight status, or magnitude of weight loss. Conclusions. In older adults, intentional weight loss was not associated with increased total mortality and may reduce mortality risk. Observational studies of weight loss, especially when intentionality cannot be rigorously established, may be misleading with respect to the effect of weight loss on mortality.
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