CRP and osteoarthritis: At the beginning of the study, basic data on age, sex, selected biochemical (ESR, CRP, GFR, hemoglobin, plasma albumin, plasma protein), and clinical parameters (the duration of RA, VAS, DAS28, BMI, the presence of cardiovascular disease, diabetes, osteoporosis, osteoporotic fractures, osteoarthritis, neoplasm) were collected.