How do people's beliefs about their illness affect how they act? Can misunderstandings of illness lead to people doing things that make their condition worse, or missing opportunities to be well and happy?
Ben Darlow and colleagues from the University of Otago Wellington explored this in his study on osteoarthritis. This is an important condition because it is common and has a major effect on people's lives. People with osteoarthritis are twice as likely to be absent from work or to retire earlier due to ill health.
The study authors interviewed a small number of people with osteoarthritis in their knee about what they thought about their illness and how they managed it. Their paper (published in BMC Rheumatology) argues that people with arthritis often think of their joint as suffering from wear and tear, and reduce their physical activity to avoid making this worse.
However, there is good evidence that physical activity actually makes osteoarthritis better, not worse. In this study, Dr Darlow explored where people got their beliefs about their illness from and how they affected their lives.
All participants in this study were sure that their osteoarthritis was caused by wear on the joint, and had what the authors called a biomechanical model of their illness. They compared their knee to a machine in which one of the components was failing.
They thought the cartilage cushioning between the bones was wearing away, so bone was now grating against bone. These ideas seemed to come mainly from health professionals. When people saw x-rays of their knee, this reinforced the idea of a failing machine.
Understandably, people reduced, avoided, or paced physical activity to avoid making this worse. They also took supplements to try to increase the cartilage. People felt that they needed to balance advice to keep active and the need to keep going with everyday life, with the damage they thought exercise was causing to their joints.
The activities recommended to them were not always things they enjoyed, and while they wanted to put their arthritis out of their minds they also needed to plan around it.
Thinking of their knee as a machine with failing parts meant that people thought their joints could only get worse over time. They might stave off this deterioration for a while but they thought they were on a downhill slide. Knee replacement surgery was seen as the only long-term solution.
The authors argue that these ideas are wrong. Contrary to what everyone in the study believed, research shows that exercise reduces the pain and stiffness of arthritis, and doesn't damage the cartilage that acts like a cushion in the joint. In fact, it can even stimulate the growth of cartilage. The authors of the study were concerned that people's beliefs about their illness were stopping them from exercising and exploring other ways to manage their illness.
The authors speculated that health professionals may use the term ''wear and tear'' to explain arthritis and to make arthritis less threatening to patients, but they point out that thinking of it this way has negative consequences. People felt they had to constantly make difficult choices between exercise and damage, to weigh up enjoying their life now with causing more pain and disability in the future.
However, the authors argue that these decisions and trade-offs are unnecessary: exercise helps us enjoy life now, and improves symptoms in the future. They recommend that health professionals specifically discuss these issues with patients, and that information resources be designed to emphasise the benefits of activity and combat the ''wear and tear'' model of arthritis.
-Pauline Norris is a research professor at the Centre for Pacific Health, Va'a O Tautai, and CHeST: the Centre for Health Systems and Technology, in the University of Otago Division of Health Sciences.
