“…Seventeen studies with a total of 1144 RA patients (mean age 49 years, 25% males) and 797 healthy controls (mean age 49 years, 31% males) were assessed [ 29 , 30 , 31 , 32 , 34 , 35 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 45 , 46 , 47 , 48 ]. Ten studies were performed in Asia [ 29 , 30 , 31 , 32 , 34 , 35 , 37 , 38 , 43 , 48 ], five in Europe [ 39 , 41 , 42 , 46 , 47 ], one in America [ 40 ], and one in Africa [ 45 ].…”