Risk factors and burden of osteoarthritis.

Osteoarthritis (OA) is one of the most common joint disorders worldwide. Its prevalence is increasing because of the growing aging of the population in developed and developing countries as well as an increase in risk factors leading to OA, particularly obesity and a sedentary lifestyle. Risk factors of OA can be divided into person-level factors (age, gender, obesity, genetics and diet) and joint-level factors (injury, malalignment and abnormal loading of the joints) that interact in a complex manner. OA is the 11th cause of disability in the world. It is responsible for activity limitations, particularly walking, and affects participation and quality of life. Patients with OA are at greater risk of all-cause mortality, particularly for cardiovascular diseases, than the general population. This excess mortality is closely associated with disability level. Consequently, strategies to reduce burden through primary and secondary prevention programs are increasingly important.