OSTEOARTHRITIS (OA) is the most prevalent form of arthritis globally, contributing significantly to disability and healthcare usage. It is also linked to various comorbidities, a connection that has received increasing attention in recent years. In their 2023 update, the European Alliance of Associations for Rheumatology (EULAR) recognized OA as a severe disease with substantial implications for both individuals and society. Despite this recognition, the majority of OA patients do not receive optimal management, which is a critical unmet need, particularly in light of additional systemic comorbidities.
To address this, the ComOA initiative combined case-control and cohort studies, involving over 3 million people from primary care databases in the UK, Netherlands, Sweden, and Spain.
The analyses presented at the 2024 EULAR congress in Vienna examined the associations between OA and 61 different comorbidities identified before and after the initial OA diagnosis. Researchers assessed the consistency of their findings across the four countries, defining congruency as results being significant and consistent in one direction across all centers.
In the four databases, there were 845,373 OA cases and 2,556,243 controls. Pooled prevalence data indicated that several conditions were more common in people with OA than in matched controls. The most prevalent conditions included chronic back pain, hypertension, allergy, cataract, vertigo, depression, and diabetes. Among 33 comorbidities studied, 10, such as fibromyalgia, polymyalgia, and chronic back pain, showed consistent evidence of association with OA at diagnosis across the four countries. The three major comorbidities that developed after an OA diagnosis were fibromyalgia, rheumatoid arthritis, and polymyalgia. No consistent association was found for 14 chronic conditions, including heart failure, diabetes, dementia, and chronic obstructive pulmonary disease, either before or after the OA diagnosis.
These findings are crucial for planning the management of people with OA and suggest that further research is needed to establish the causal relationships between OA and its comorbidities.