The article presents the results of studies of immunological and biochemical characteristics of diseases of the osteoarticular system among residents of Bishkek. The studies were carried out on residents of Bishkek, men and women aged 21–74, in the spring of 2019, in the fall of 2019 and in the fall of 2020. A total of 1358 people were examined for ACCP, of which 282 residents of Bishkek were found to have an ACCP content higher than the norm, among which 238 were women and 44 were men. The level of antibodies to cyclic citrullinated peptide (ACCP) was determined in blood serum by immunochemiluminescence analysis. Biochemical studies aimed at identifying the activity of the process and immune inflammation consisted of determining the levels of rheumatoid factor (RF), C-reactive protein (CRP), Antistreptolysin-O (ASL-O) and uric acid (MC) according to generally accepted methods. Out of the selected 282 Bishkek residents, 17 men and 82 women belong to the confirmation group, while 27 men and 156 women are in the group of people with increased levels of ACCP were first established. ACCPs mainly belong to the IgG class and are found in the blood at the earliest stages of rheumatoid arthritis disease (1–2 years before the onset of the first symptoms) and their specificity in rheumatoid arthritis is about 97%. They are detected at very early stages of the disease, which explains the distribution of the surveyed residents of Bishkek by groups. Analysis by sex distribution showed that in all groups women prevail than men, since it is known from scientific literature source that diseases of the osteoarticular system, in particular rheumatoid arthritis, are more susceptible to women than men. Women get sick more often than men 2–5 times more, which was found in our studies, the ratio of men and women is on average 1:3.4–5.6. It has been proven that damage to the osteoarticular system can occur at any age. According to our data, 47.7% of the total number of surveyed men were aged 35–60 years, 45.5% were men aged 61–74 years. At the same time, among women, 37% were aged 35–60 years, 36.3% were women aged 61–74 years. According to scientific literature sources, the incidence of rheumatoid arthritis increases with age, over 60 years old reaches its maximum value (more than 2%), the population is aging when RA grows. Gender differences are also lost, the ratio of women to men is 2:1 or less. At the same time, rheumatoid arthritis can develop at any age, most often from 35 to 50 years, but it can also be in childhood and in the elderly. According to our results, among women under 35 years of age in the confirmation group, the prevalence of RA was 28.3%, at the age of 36-60 years 58.8%, and at the age of over 61 years — 43.6%. And in the group of primary confirmation, women under 35 years old accounted for 16.7%, at the age of 36-60 they make up 20.4% and over 60 years old — 28.5%. As you know, ACCP can be detected in 30% of cases of seronegative rheumatoid arthritis (negative for rheumatoid factor), which is advisable in the diagnosis of early seronegative RA, in differential diagnosis with other rheumatic diseases. Elevated ACCP levels in healthy individuals indicate a significant increase in the risk of developing RA. Rheumatoid factor is an autoimmune antibody, an immunoglobulin protein (IgM) produced by the body's immune system. Autoantibodies attack their own tissues, mistaking them for foreign ones. Although the nature of rheumatoid factor is still poorly understood, its presence is an indicator of inflammatory and autoimmune processes. With rheumatoid arthritis symptoms, high rheumatoid factor levels are likely to indicate seropositive rheumatoid arthritis. However, even a negative test result does not exclude that the patient has these diseases. Antibodies to cyclic citrullinated peptide and RF are currently recognized as an informative serological marker of rheumatoid arthritis. Based on studies carried out at different times of the year (spring, autumn 2019, autumn 2020), it was found that the season does not have a significant effect on the content of the ACCP level, although residents of Bishkek (men and women) often complain of pain in the joints in the fall. than in the spring. This is confirmed by the highest content of ACCP among women, as well as men over 35 years old to 74 years old.