Factors associated with osteoporosis medication use in Japanese patients with rheumatoid arthritis: Results from the Institute of Rheumatology Rheumatoid Arthritis cohort study

OBJECTIVES: This study aimed to evaluate factors associated with osteoporosis medication use in Japanese patients with rheumatoid arthritis (RA). METHODS: Patients with RA who enrolled in our cohort completed self-administered questionnaires which included questions regarding their osteoporosis medications. Logistic regression was used to determine the association of variables with the use of these medications. RESULTS: Among 5660 Japanese patients with RA who responded to the questionnaires (mean age, 61.8 years; 86.0% female), 1983 patients (35.0%) and 1211 patients (21.4%) reported taking osteoporosis medications and antiresorptive agents, respectively. In multivariate models, age, female sex, lower body mass index (BMI), self-reported fracture history, Japanese Health Assessment Questionnaire-Disability Index (JHAQ-DI), daily dosage of prednisone (PSL), weekly dosage of methotrexate (MTX), and concomitant use of hypertension and hyperlipidemia medications were significantly associated with the use of osteoporosis medications (P < 0.05). Among women with RA, the use of hypertension medications was significantly correlated with the use of both osteoporosis medications and antiresorptive agents (P < 0.05). CONCLUSIONS: Age, female sex, a lower BMI, duration of RA, self-reported fracture history, JHAQ-DI, daily dosage of PSL, weekly dosage of MTX, and the use of medications for hypertension and hyperlipidemia appear to be associated with the use of osteoporosis medications in Japanese patients with RA.