A study that draws on data from more than 100,000 people finds a link between diabetes and an increased risk of osteoporosis, osteoarthritis, and rheumatoid arthritis.

In the United States, over 100 million people are living with diabetes and prediabetes.

Type 2 diabetes is a chronic condition requiring lifelong management; the disease impacts a number of systems in the body.

As scientists spend increasing amounts of time investigating diabetes and its effects, they are discovering relationships with various other conditions.

For instance, previous studies have concluded that people with diabetes are likelier to report musculoskeletal pain than people without diabetes. However, it is unclear whether this increase is due to an increased risk of chronic bone and joint conditions.

Investigating links

Recently, a team at Nordsjaellands University Hospital in Hillerød, Denmark, set out to gain a better understanding of the potential interactions between diabetes, osteoarthritis, rheumatoid arthritis, and osteoporosis.

The results were presented earlier this week at the European Association for the Study of Diabetes Annual Meeting, held in Berlin, Germany.

In order to investigate, the scientists took data from the 2013 Danish National Health Survey; in all, they had access to the records of 109,218 people aged 40 or older. Of these people, 8.5% were diagnosed with diabetes; also, they were more likely to be male, older, and have a higher BMI.

Once the investigators had controlled for risk factors, such as age, gender, and BMI, a significant pattern still emerged.

They found that people with diabetes were 33% more likely to have osteoarthritis; they were also more likely to have rheumatoid arthritis and osteoporosis (the risk increased by 70% and 29%, respectively).

Aside from these specific conditions, when compared with people without diabetes, those with diabetes were 27% more likely to report back pain and 29% more likely to have shoulder and neck pain.

What is driving the association?

The authors believe that the particularly pronounced relationship between rheumatoid arthritis and diabetes could be due to the presence of chronic inflammation in both conditions. There may be other factors at play, the authors explain.

"Whilst steroids are used in the treatment of [rheumatoid arthritis]," they explain, "steroids also increase the risk of the development of type 2 diabetes."

Lead researcher Dr. Stig Molsted offers another possible explanation for the link between arthritis and diabetes, explaining, "It's likely that the chronic pain experienced by people with arthritis may be a barrier to exercising, which is also a risk factor for type 2 diabetes."

To back this up, in another part of the analysis, the researchers demonstrated that people with diabetes who were more active had a reduced risk of back, shoulder, and neck pain. The researchers hope that their findings might help physicians guide their patients.

"Health-care professionals should make patients with diabetes aware that regular exercise is a recognized treatment for diabetes and arthritis, and can have positive effects on both blood sugar control as well as musculoskeletal pain."

–Dr. Stig Molsted

It is important to note that this study was observational, so cause and effect cannot be picked apart. There may be risk factors that these conditions share that we do not yet understand. Also, as the authors explain, the data they used are based on participants' self-reports, which makes them considerably less reliable.

Due to the enormous burden of diabetes, arthritis, and osteoporosis on the US, the relationships between them are important to understand.

By unpicking the way in which chronic diseases interact, scientists can help create meaningful advice for patients; potentially, it could also offer insight into the mechanisms behind these currently incurable conditions.