 Clinical evaluation of synovitis in rheumatoid arthritis RA is difficult in obese and overweighted patients, due to the fat pad located around the joint, that can over- or under estimate the number of joints regarded as swollen by clinical examination. RA in obese and overweighted patients has several distinctive characteristics as compared to the disease observed in normally weighted subjects: diease activity assessed by composites scores such as Disease Activity Score DAS28 or Simple Disease Activity Index SDAI is higher, while response to treatment and severity asessed by radiographic progression are lower. 