Introduction
In this study, we aimed to identify whether biologics treatment in rheumatoid arthritis (RA) patients was capable of preventing comorbidities in this population [1]. Biologics have been used for more than 15 years in Taiwan, and their efficacy has been discussed elsewhere and confirmed to be protective against joint structure damage in RA patients. Whether biologics’ beneficial effect influences comorbidities throughout the body is still under evaluation.
Among RA patients, the first comorbidities that need to be considered are cardiovascular events, followed by metabolic problems like diabetes and dyslipidemia. Diabetes mellitus, together with a number of risk factors of metabolic origin, can result in an increased risk for early mortality [2]. Considerable evidence has demonstrated that chronic low-grade inflammation caused by activating the innate immune system is vital in the pathogenesis of diabetes and other major complications. Diabetes is also a risk factor for cardiovascular comorbidities itself. In addition to these common comorbidities, RA is an autoimmune disease that can overlap other rheumatic or orthopedic-related comorbidities, such as gout, osteoporotic fractures, inflammatory bowel disease, psoriasis, etc. In the long run, the malignancy could be devastating due to chronic inflammation and tissue damage in RA patients.
Several other comorbidities that need to be considered include infectious diseases caused by the immune deviation of RA patients or the hepatic or nephrotic damage caused by medication side effects. Such pulmonary diseases as interstitial lung disease, asthmatic bronchitis, or chronic obstructive pulmonary disease are all listed in our analysis (Table 1).
The purpose of this study was to determine the long-term effect of biologic agents on RA patients in a real-world setting by using a nationwide database. Therefore, we designed a simulated analytic cohort study with strict selection and matching to determine whether long-term biologic agent use could affect the overall mortality rate of RA patients. In the current retrospective study, we compared the mortality rate between biologics users and non-biologics users in RA patients in Taiwan.