Investigation of comorbidities associated with osteoarthritis

Osteoarthritis is the most common arthritis worldwide and has an increasing global burden of disability and health care utilization. It is also associated with various comorbidities, and this link has gained attention in recent years.

In the 2023 update of their recommendations for the management of osteoarthritis, EULAR – the European Alliance of Societies for Rheumatology – recognizes osteoarthritis as a serious disease with significant implications for both the individual and society. However, most people with osteoarthritis do not receive optimal management. and this represents a significant unmet need—especially when considering additional systemic comorbidities. To investigate this further, ComOA combined case-control and cohort studies of more than 3 million people in primary care in the UK, the Netherlands, Sweden and Spain. The analyses—shared at the 2024 EULAR conference in Vienna—examined the associations between osteoarthritis and 61 different comorbidities identified before and after the first diagnosis of osteoarthritis. The researchers then tested the similarity of their findings across the four countries—where relevance was determined if all centers’ results were significant and favored in one direction.

There were 845,373 osteoarthritis cases and 2,556,243 controls in the four databases. Pooled prevalence data showed several conditions that were more common in people with osteoarthritis than in matched controls. The conditions with the highest prevalence were chronic low back pain, hypertension, allergy, cataract, vertigo, depression and diabetes. Of the 33 comorbidities studied, 10 such as fibromyalgia, polymyalgia and chronic back pain showed concurrent evidence of association with osteoarthritis at diagnosis in the four countries. The three main comorbidities that developed after the diagnosis of osteoarthritis were fibromyalgia, rheumatoid arthritis, and polymyalgia. No corresponding evidence of association with before or after osteoarthritis diagnosis was found for 14 chronic conditions, including heart failure, diabetes, dementia and chronic obstructive pulmonary disease.

These are important findings to consider in planning the management of people with osteoarthritis and suggest that further research is needed to establish the causal relationship between osteoarthritis and its comorbidities.