Using population registers, the researchers studied approximately 469 000 people living in Skåne, Sweden, who in 2003 were between 45 and 84 years old and followed them through to 2014. The group included 16 000 patients with knee arthritis, 9 000 with hip arthritis, 4 000 with wrist arthritis and 5 500 with other forms of osteoarthritis. They had all been diagnosed in 2003 or before.
“We looked at the cause of death for those who died between 2004 and 2014 and who had previously been diagnosed with osteoarthritis and compared the results with the rest of the population in the same region. The groups were not different in terms of most causes of death, but we saw the risk of mortality from cardiovascular disease was higher for those with an osteoarthritis diagnosis. The risk did not increase in the short term after the osteoarthritis diagnosis, but the longer a person had had osteoarthritis, the higher the risk of mortality from cardiovascular diseases compared with the background population, e.g. if a person had a knee arthritis diagnosis for 9 to 11 years, the risk was 16 per cent higher”, says Martin Englund, professor at Lund University and physician at Skåne University Hospital, who led the study.
This means that for every 100 000 inhabitants who have had osteoarthritis for 9–11 years, 40 more die of cardiovascular diseases per year, compared with the population without osteoarthritis (in corresponding gender and age distribution).
The study did not investigate the mechanisms behind osteoarthritis and cardiovascular disease and the causal link is not fully known. However, Martin Englund has a theory on the reason behind the results.
“Osteoarthritis causes pain, which often results in people not being as mobile and becoming sedentary instead. Thus, there is a risk of weight gain, which we know leads to secondary diseases, including cardiovascular diseases. There are also other background factors in common for osteoarthritis and cardiovascular disease. Inflammation can be a contributory cause of osteoarthritis, and can also lead to an increased risk of cardiovascular disease. Regardless, it’s important to be physically active and keep body weight in check. In many countries there are special education programs for those suffering from osteoarthritis where you can get information on the disease as well as help and exercise advice”, concludes Martin Englund.