Introduction
DEGENERATIVE JOINT DISEASE
Osteoarthritis(OA) is a degenerative joint disease related to cartilage that affects approximately 300 million people worldwide [Previous studies suggest that the homeostasis regulation of chondrocytes depends on the local renin–angiotensin system. Thus, angiotensin-converting enzyme (ACE) inhibitors or angiotensin-II receptor blockers may have therapeutic potential for knee OA [Mendelian randomization is a statistical method that uses genetic variation as an instrumental variable to estimate the causal relationship between exposure and outcome [