Osteoarthritis (OA) is the most common form of arthritis, affecting almost 10 per cent of Australians, and is the most common condition leading to knee and hip replacements.

Between 2008–2009 and 2017–2018 there was a 27 per cent increase in the number of knee replacements performed in Australia (from 144 to 183 per 100,000 population).

A study published in the Annals of Internal Medicine in November (Bennell et al 2021) has shown that delivering a telehealth exercise program with and without an accompanying weight loss program is effective in treating knee OA in people with overweight or obesity.

The study was a collaboration between researchers led by Professor Kim Bennell and Professor Rana Hinman of the University of Melbourne’s Centre for Health, Exercise and Sports Medicine (CHESM), and Australian health insurer Medibank.

‘We were approached by Medibank a few years back because one of their biggest growth areas was joint replacement surgery.

'They wanted to design and evaluate an accessible lifestyle management program to see if they could improve outcomes for their members with OA, thus reducing the need for joint replacement surgery,’ says Kim.

Joint replacements are expensive surgeries with risks and don’t necessarily lead to good outcomes for all patients.

At CHESM, a lot of the research is looking at alternatives to surgery, including exercise and weight loss.

‘We know exercise and weight loss are key recommended treatments, but the problem is that many patients are not undertaking these treatments.

'Reasons for this may include healthcare professionals not recommending them, or because patients don’t have access to such programs,’ says Kim.

Finding ways to improve outcomes for people with knee osteoarthritis and prevent the need for costly joint replacement surgeries was also high on the list of desired outcomes for Medibank.

‘The Better Knee, Better Me trial was developed after we saw increasing rates of osteoarthritis and a gap in the availability and uptake of healthcare programs aiming to prevent the need for future knee replacement surgery, via supported exercise and weight loss.

'We partnered with physiotherapy experts from the University of Melbourne and weight management experts from Austin Health to design and test the program,’ says Medibank’s Head of Health Strategy and Services, Dr Catherine Keating, who was part of the study team.

Building on existing studies, including one demonstrating the effectiveness of physiotherapists delivering programs via videoconference, the CHESM team and Medibank designed a telehealth program to compare an exercise plus weight loss program versus an exercise-only program versus an online education control.

‘From a scientific perspective, we were also interested in looking at how much additional benefit you get for knee pain and function from weight loss over and above what you get from exercise, because the clinical guidelines all recommend exercise and weight loss, but the extra benefits for knee OA symptoms are not entirely clear,’ Kim says.

The resulting study comprised 415 participants recruited from Medibank’s members, who were randomly assigned to the exercise, diet plus exercise or control groups.

All three groups were provided with access to a website with information about OA, including treatment options, pain management, exercise and weight loss.

The exercise group received a six-month-long exercise program including six video consultations with a physiotherapist for exercise, self-management advice and behavioural counselling as well as the resources needed to complete the program, while the diet plus exercise group received the same exercise program, plus a very low calorie ketogenic diet program and six video consultations with a dietitian, followed by a transition to healthy eating and associated resources.

The participants were evaluated at the six and 12-month marks for knee pain and physical function as well as for a variety of secondary measures.

The results showed that both programs were beneficial for pain and physical function—the two primary outcomes—at six months and 12 months, with the diet and exercise program only slightly more effective than the exercise-only program for these outcomes.

Beneficial results were seen for a range of other outcomes, including weight loss of around 10 kilograms in the diet plus exercise group, reduced use of pain medication, improved quality of life and a reduced willingness to undergo knee surgery.

‘We also did some qualitative research interviewing a subsample of the diet plus exercise participants from the trial.

'The results showed that people found the program to be highly acceptable valuing the support from both physiotherapists and dietitians and the convenience of the remote delivery.

'Many people had great outcomes with the weight loss and saw benefits, not just for their knee OA but for their overall health and wellbeing,’ says Kim.

A health economic evaluation is also being performed and indicates that the programs are cost-effective.

Catherine says that from Medibank’s perspective, the study really delivered.

‘We found the research partnership fantastic.

'We were able to recruit more than 400 of our customers into an Australian-first clinical trial that was designed by leaders in osteoarthritis management (if they met the specific eligibility criteria).

'We were also able to work with our research partners to fast-track the usually “very long” process between the clinical trial phase and progression to a large-scale health service due to the positive early results of the trial,’ she says.

Based on the study results, Medibank has now rolled out a modified version of the diet and exercise program called Better Knee, Better Me to eligible members.

Kim says that throughout the trial, Medibank was very respectful of the scientific process and was mindful of not compromising the scientific integrity of the trial.

‘For me, it was probably the most rewarding project I’ve done in my 25-year career.

'It was a true collaboration between stakeholders and researchers and showed that the pipeline to having an impact can be really short, rather than the research just being published in a journal article and waiting for some scientists and physiotherapists to read for it to make a difference,’ Kim says.

An additional study is looking at whether physiotherapists can deliver the diet program as well as the exercise program, Kim says, which could potentially streamline the program by reducing the number of professionals needed to deliver it.

‘There are a lot more physios than there are dietitians around and we felt we could integrate the exercise and the weight loss programs,’ she explains.

This could be useful in settings where access to dietitians is limited.

The study has also opened doors to new opportunities.

Kim and the CHESM team are about to start on the Better Hip study, examining the effects of exercise and diet programs on hip OA, which is funded by the Australian Government’s Medical Research Future Fund in partnership with Medibank, Dietitians Australia and the APA.

Reference

Bennell et al (2021). Comparing video-based, telehealth- delivered exercise and weight loss programs with online education on outcomes of knee osteoarthritis: a randomized trial. Ann Intern Med. 2021 Nov 30. doi: 10.7326/M21-2388