Physical function after dietary weight loss in overweight and obese adults with osteoarthritis: a systematic review and meta-analysis

The effects of a 6-month weight loss intervention on physical function and serum biomarkers in older adults with and without osteoarthritis

Objective

To examine the effects of a 6-month weight loss intervention on physical function, inflammatory biomarkers, and metabolic biomarkers in both those with and without osteoarthritis (OA).

Design

59 individuals ≥60 years old with obesity and a functional impairment were enrolled into this IRB approved clinical trial and randomized into one of two 6-month weight loss arms: a higher protein hypocaloric diet or a standard protein hypocaloric diet. All participants were prescribed individualized 500-kcal daily-deficit diets, with a goal of 10% weight loss. Additionally, participants participated in three, low-intensity, exercise sessions per week. Physical function, serum biomarkers and body composition data were assessed at the baseline and 6-month timepoints. Statistical analyses assessed the relationships between biomarkers, physical function, body composition, and OA status as a result of the intervention.

Results

No group effects of dietary intervention were detected on any outcome measures (multiple p ​> ​0.05). During the 6-month trial, participants lost 6.2 ​± ​4.0% of their bodyweight (p ​< ​0.0001) and experienced improved physical function on the Short-Performance-Physical-Battery (p ​< ​0.0001), 8-foot-up-and-go (p ​< ​0.0001), and time to complete 10-chair-stands (p ​< ​0.0001). Adiponectin concentrations (p ​= ​0.0480) were elevated, and cartilage oligomeric matrix protein (COMP) concentrations (p ​< ​0.0001) were reduced; further analysis revealed that reductions in serum COMP concentrations were greater in OA-negative individuals.

Conclusions

These results suggest that weight loss in older adults with and without OA may provide a protective effect to cartilage and OA. In particular, OA-negative individuals may be able to mitigate changes associated with OA through weight loss.

The effects of weight-lowering pharmacotherapies on physical activity, function and fitness: A systematic review and meta-analysis of randomized controlled trials

Weight-lowering pharmacotherapies provide an option for weight management; however, their effects on physical activity, function, and cardiorespiratory fitness are not fully understood. We conducted a systematic review and meta-analysis of randomized controlled trials to investigate the effect of licensed weight loss pharmacotherapies on physical activity, physical function, and cardiorespiratory fitness in individuals with obesity. Fourteen trials met our prespecified inclusion criteria: Five investigated liraglutide, four semaglutide, three naltrexone/bupropion, and two phentermine/topiramate. All 14 trials included a self-reported measure of physical function, with the pooled findings suggesting an improvement favoring the pharmacotherapy intervention groups (SMD: 0.27; 95% CI: 0.22 to 0.32) and effects generally consistent across different therapies. Results were also consistent when stratified by the two most commonly used measures: The Short-Form 36-Item Questionnaire (SF-36) (0.24; 0.17 to 0.32) and the Impact of Weight on Quality Of Life-Lite (IWQOL-Lite) (0.29; 0.23 to 0.35). Meta-regression confirmed a significant association between pharmacotherapy induced weight loss and improved physical function for IWQOL-Lite (p = 0.003). None of the studies reported a physical activity outcome, and only one study reported objectively measured cardiorespiratory fitness. Improvements in self-reported physical function were observed with weight loss therapy, but the effect on physical activity or objectively measured physical function and fitness could not be determined.

Effects of total diet replacement programs on mental well-being: A systematic review with meta-analyses

This systematic review with meta-analyses assessed the effects of total diet replacement (TDR) programs on mental well-being in clinical trial participants with a body mass index greater than or equal to 25 kg/m² . TDR programs involve replacing all dietary requirements with nutritionally replete formula foods and are generally administered to induce rapid weight loss. To date, it is largely unclear what effects TDR programs may have on mental well-being, particularly in the long-term. To address this, we screened 25,976 references across six databases and extracted 35 publications. These 35 publications provided sufficient data to evaluate the effects of TDR programs on depression, anxiety, stress, positive affect, negative affect, vitality, role-emotional, social functioning, mental health, mental composite summary score, self-esteem, and general psychological health in 24 meta-analyses. Due to the lack of research comparing TDR programs to comparator groups, 22 of our 24 meta-analyses explored change in these mental well-being sub-domains over time in TDR programs without comparators. Specifically, we assessed the change from pre-diet (before the TDR program) to either post-diet (up to and including two months after the TDR program); and/or follow-up (more than two months after the TDR program). For depression and anxiety, we were also able to assess the change from pre-diet to mid-diet (which fell within two weeks of the diet half-way point). The remaining two meta-analyses assessed the difference in depression scores between a TDR group and a food-based comparator group from pre-diet to post-diet and from pre-diet to follow-up. Across all meta-analyses, our results found no marked adverse effects of TDR programs on any mental well-being sub-domain. In fact, clear improvements were observed for depression, anxiety, stress, vitality, role-emotional, and social functioning at post-diet. Interestingly, the improvements for depression, vitality and role-emotional were maintained at follow-up. All improvements were observed in meta-analyses without comparators. While the two comparator-based meta-analyses showed no difference between TDR programs and food-based diets in depression symptoms, there was low statistical power. For all meta-analyses containing three or more independent samples, we constructed prediction intervals to determine the range within which the mean of the true effects may fall for future populations. While these prediction intervals varied between sub-domains, we found that mean depression scores are only likely to increase (i.e., depression will worsen) in less than 3% of future TDR interventions which meet our inclusion/exclusion criteria. Taken together, we concluded that for adults with a body mass index greater than or equal to 25 kg/m² , TDR programs are unlikely to lead to marked adverse effects on mental well-being. These findings do not support the exclusion of participants from trials or interventions involving TDR programs based on concerns that these programs may adversely affect mental well-being. In fact, by excluding these participants, they may be prevented from improving their metabolic health and mental well-being.

Effectiveness of a telehealth physiotherapist-delivered intensive dietary weight loss program combined with exercise in people with knee osteoarthritis and overweight or obesity: study protocol for the POWER randomized controlled trial

BACKGROUND

Obesity is associated with knee osteoarthritis (OA). Weight loss, alongside exercise, is a recommended treatment for individuals with knee OA and overweight/obesity. However, many patients cannot access weight loss specialists such as dietitians. Innovative care models expanding roles of other clinicians may increase access to weight loss support for people with knee OA. Physiotherapists may be well placed to deliver such support. This two-group parallel, superiority randomized controlled trial aims to compare a physiotherapist-delivered diet and exercise program to an exercise program alone, over 6 months. The primary hypothesis is that the physiotherapist-delivered diet plus exercise program will lead to greater weight loss than the exercise program.

METHODS

88 participants with painful knee OA and body mass index (BMI) > 27 kg/m² will be recruited from the community. Following baseline assessment, participants will be randomised to either exercise alone or diet plus exercise groups. Participants in the exercise group will have 6 consultations (20-30 min) via videoconference with a physiotherapist over 6 months for a strengthening exercise program, physical activity plan and educational/exercise resources. Participants in the diet plus exercise group will have 6 consultations (50-75 min) via videoconference with a physiotherapist prescribing a ketogenic very low-calorie diet with meal replacements and educational resources to support weight loss and healthy eating, plus the intervention of the exercise only group. Outcomes are measured at baseline and 6 months. The primary outcome is percentage change in body weight measured by a blinded assessor. Secondary outcomes include self-reported knee pain, physical function, global change in knee problems, quality of life, physical activity levels, and internalised weight stigma, as well as BMI, waist circumference, waist-to-hip ratio, physical performance measures and quadriceps strength, measured by a blinded assessor. Additional measures include adherence, adverse events, fidelity and process measures.

DISCUSSION

This trial will determine whether a physiotherapist-delivered diet plus exercise program is more effective for weight loss than an exercise only program. Findings will inform the development and implementation of innovative health service models addressing weight management and exercise for patients with knee OA and overweight/obesity.

TRIAL REGISTRATION

NIH US National Library of Medicine, Clinicaltrials.gov NCT04733053 (Feb 1 2021).

Epigenetic Regulation of Chondrocytes and Subchondral Bone in Osteoarthritis

The aim of this review is to provide an updated review of the epigenetic factors involved in the onset and development of osteoarthritis (OA). OA is a prevalent degenerative joint disease characterized by chronic inflammation, ectopic bone formation within the joint, and physical and proteolytic cartilage degradation which result in chronic pain and loss of mobility. At present, no disease-modifying therapeutics exist for the prevention or treatment of the disease. Research has identified several OA risk factors including mechanical stressors, physical activity, obesity, traumatic joint injury, genetic predisposition, and age. Recently, there has been increased interest in identifying epigenetic factors involved in the pathogenesis of OA. In this review, we detail several of these epigenetic modifications with known functions in the onset and progression of the disease. We also review current therapeutics targeting aberrant epigenetic regulation as potential options for preventive or therapeutic treatment.

Comparing Video-Based, Telehealth-Delivered Exercise and Weight Loss Programs With Online Education on Outcomes of Knee Osteoarthritis : A Randomized Trial

BACKGROUND

Scalable knee osteoarthritis programs are needed to deliver recommended education, exercise, and weight loss interventions.

OBJECTIVE

To evaluate two 6-month, telehealth-delivered exercise programs, 1 with and 1 without dietary intervention.

DESIGN

3-group, parallel randomized (5:5:2) trial. (Australian New Zealand Clinical Trials Registry: ACTRN12618000930280).

SETTING

Australian private health insurance members.

PARTICIPANTS

415 persons with symptomatic knee osteoarthritis and a body mass index between 28 and 40 kg/m2 who were aged 45 to 80 years.

INTERVENTION

All groups received access to electronic osteoarthritis information (control). The exercise program comprised 6 physiotherapist consultations via videoconference for exercise, self-management advice, and behavioral counseling, plus exercise equipment and resources. The diet and exercise program included an additional 6 dietitian consultations for a ketogenic very-low-calorie diet (2 formulated meal replacements and a low-carbohydrate meal daily) followed by a transition to healthy eating, as well as nutrition and behavioral resources.

MEASUREMENTS

Primary outcomes were changes in knee pain (numerical rating scale [NRS] of 0 to 10, higher indicating worse) and physical function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]; scale, 0 to 68, higher indicating worse) at 6 months (primary time point) and 12 months. Secondary outcomes were weight, physical activity, quality of life, mental health, global change, satisfaction, willingness to have surgery, orthopedic appointments, and knee surgery.

RESULTS

A total of 379 participants (91%) provided 6-month primary outcomes, and 372 (90%) provided 12-month primary outcomes. At 6 months, both programs were superior to control for pain (between-group mean difference in change on NRS: diet and exercise, -1.5 [95% CI, -2.1 to -0.8]; exercise, -0.8 [CI, -1.5 to -0.2]) and function (between-group mean difference in change on WOMAC: diet and exercise, -9.8 [CI, -12.5 to -7.0]; exercise, -7.0 [CI, -9.7 to -4.2]). The diet and exercise program was superior to exercise (pain, -0.6 [CI, -1.1 to -0.2]; function, -2.8 [CI, -4.7 to -0.8]). Findings were similar at 12 months.

LIMITATION

Participants and clinicians were unblinded.

CONCLUSION

Telehealth-delivered exercise and diet programs improved pain and function in people with knee osteoarthritis and overweight or obesity. A dietary intervention conferred modest additional pain and function benefits over exercise.

PRIMARY FUNDING SOURCE

Medibank, the Medibank Better Health Foundation Research Fund, and a National Health and Medical Research Council Centre of Research Excellence.