Diabetes mellitus in patients with rheumatoid arthritis in the Republic of Karelia
Objective: to estimate the incidence of diabetes mellitus (DM) in patients with rheumatoid arthritis (RA) in the Republic of Karelia and to analyze the types of carbohydrate metabolism disorders. Patients and methods. The investigation enrolled 889 patients aged 18 years and older with RA treated in the Rheumatology Department, V.A. Baranov Republican Hospital (Petrozavodsk), in 2000 to 2019. Among them, there were 709 (79.8%) women and 180 (20.2%) men; the median age was 59 [52; 66] years; the median duration of RA was 6.5 [1.75; 13] years. Most patients were found to have positive rheumatoid factor (68.3%), the second and more advanced radiological stages (90.6%), and moderate and high RA disease activity (84.8%). Methotrexate as a mainstay disease-modifying anti-rheumatic drug was taken by 68.2%; biological agents and glucocorticoids (GCs) were used in 4.8 and 3.3%, respectively. The incidence of DM and its types and risk factors (RFs) were analyzed. Results and discussion. DM was recorded in 67 (7.5%) RA patients (55 women and 12 men; the median age was 62 [56; 66] years). Among these patients, 9 (1.0%) patients with RA were observed to have type 1 DM, 50 (5.6%) and 8 (0.9%) patients had steroid-induced DM (SIDM), and type 2 DM, respectively. In 55.5% of cases, type 1 DM was represented by latent autoimmune diabetes in adults (LADA), which is of late onset. SIDM was detected in 75% of patients over 60 years of age who had RFs for type 2 DM. In this study, the incidence of type 2 DM in RA patients exceeded official figures in the general population of the Russian Federation, but was close to the predicted prevalence rates of type 2 DM. Patients with RA and type 2 DM had major RFs, such as age over 45 years, hypertension, overweight or obesity; moreover, 60% of patients were found to have a combination of these factors. Conclusion. RA patients showed a higher incidence rate of carbohydrate disorders of different types; the number of cases of type 1 DM and type 2 DM among the examined patients with RA exceeded that in the regional DM registries in the general population in the Republic of Karelia. It seems advisable to screen for carbohydrate disorders in patients with RA, especially in the presence of RFs for type 2 DM and during systemic therapy with GCs.