Weight loss key to managing obese patients with osteoarthritis

It is the most common type of arthritis affecting the cartilage of a joint that is caused by injury or wear and tear of the joints over the years.

The disease which causes pain, disability, and loss of function, usually affects the hands, hips, and knees, when the cartilage that cushions the ends of the bones break down over time.

The chronic joint disorder prevents people from performing everyday activities such as opening or closing hands, or walking down stairs.

Worldwide, about seven per cent or 500 million people have osteoarthritis.

In Malaysia, a 2019 local study on adults aged 55 and above in Kuala Lumpur and Petaling Jaya showed that 30.8 per cent of respondents had reported knee osteoarthritis symptoms.

WHAT ARE THE CAUSES OF OA?

At a recent webinar on 'Osteoarthritis Care and Obesity Comorbidities - Weight Loss Solutions for Southeast Asia', Consultant Rheumatologist at Subang Jaya Medical Centre, Dr Yeap Swan Sim said age is one of the strongest predictors (risk factors) for OA.

"This has been supported by recent figures published for 2021 which found that just below 10 per cent of men and 14 per cent of women aged 50 to 69 years have symptomatic hip and knee osteoarthritis.

She added that gender and genetics play an important role too, as women are more susceptible to developing osteoarthritis. The data also suggests a heritability risk of 50 per cent or more, indicating that half of the susceptibility to osteoarthritis is explained by genetic factors.

"Not only age and gender, those who do high intensity training such as athletes and marathon runners are also more prone to osteoarthritis, because of joint stress and trauma. About five per cent of new knee osteoarthritis cases are related to a previous injury," she added.

AGING, OBESE POPULATION

Dr Yeap who is also vice-president of the Malaysian Osteoporosis Society said OA will become more prevalent with an aging and increasingly obese population.

According to the Department of Statistics Malaysia (DOSM), Malaysia is expected to become an aging nation by 2030. An aging population is defined as one in which those aged 65 years and above make up at least 15 per cent of the total population.

"Research has shown that 50 per cent of knee osteoarthritis in the United States (US) could have been avoided if there was no obesity in the population. In China, where the obesity rate is lower, OA accounted for only eight per cent.

"Using a Body Mass Index (BMI) of above 27.4 to define obesity, Malaysia has the highest rate of obesity among Asian countries. In a study done in 2019, 15.6 per cent of our population were obese," she said, adding that those who are obese experience more severe joint degeneration and a greater proportion (of this community) requires hip, knee or joint replacement.

Another panelist, Professor of Research at Parker Institute, Frederiksberg Hospital of Copenhagen Prof Henning Bliddal, quoted a study in the US which showed a 15 per cent increase in risk of knee osteoarthritis for each unit of BMI point above 27. Such data also shows that the risk of hand osteoarthritis almost doubles with a BMI above 30.

"The typical weight that can be accommodated within the joint while walking is three times that of your body weight. (This increases) if you start running or walking fast. This means that if you lose a kilo of weight, that joint will profit at least three to four times, in terms of force," he explained.

LOSE SOME, WIN SOME

The best possible action to combat osteoarthritis is by losing weight, said Prof Henning, as he quoted a weight loss study trial in Copenhagen recently which turned out to be a huge success as participants not only lost weight and maintained the weight loss, but were also healthier.

"The study had three phases -16 weeks, 52 weeks and three years. The first phase started out with participants undertaking a low energy diet, where they lost an average of 10 kg in the first 16 weeks. That became an inspiration for the participants to carry on with the weight loss.

"While the second and third phases continued to use various diet management methods such as meal replacements and intermittent diets. Those who kept to their support groups were able to maintain their weight over the years. They had lost mostly fat, and very little of their lean meat, while having a better vitamin D levels. Blood pressure and cardiovascular health had also greatly improved," he said.

Other than regular exercises and weight loss regime, patients can also opt for advanced pharmacological treatment that includes cycles of non-steroidal anti-inflammatory drugs (NSAIDs) and intraarticular injections which help to relieve pain and reduce inflammation.

Knee replacement surgery is only recommended as a last resort, in cases where there is a severe drop in quality of life, Prof Henning added.

Meanwhile, Dr Yeap advised patients to maintain simple exercises to strengthen joints. Some recommended activities for those with knee osteoarthritis are Tai Chi, yoga, cycling, walking, aquatic exercise as well as strength and neuromuscular training.

"Land-based exercises such as strength training and aerobic exercises can reduce pain and improve physical function. A lot of people think that we need to just do leg exercises but any kind of exercise can be helpful for patients with knee osteoarthritis. Simple things like walking will be helpful, apart from actual strength training exercises which will improve muscle and balance.

"However, until now, there is no scientific evidence to show that taking supplements or eating cartilage-rich foods such as a dish of chicken feet can help patients with osteoarthritis. Furthermore, many supplements are just anti-inflammatory. They help to relieve pain, but they do not actually heal or stop the degradation," she explained.