A clear difference was reported between rheumatoid arthritis (RA) patients with and without biological Disease-Modifying Antirheumatic Drugs (bDMARDs) concerning age, comorbid pattern and health care consumption. 

Rheumatoid arthritis is a long-lasting inflammatory disease that is more common in women and occurs mainly at the age of 50 years or above.  Treatment with tumor necrosis factors inhibitors (TNFi) and other bDMARDs, such as Anakinra (interleukin-1 receptor inhibitor), Rituximab (monoclonal antibody against CD20 on B-cells), Abatacept (targeting T-cells activation) and Tocilizumab (interleukin-6 receptor inhibitor) has significantly improved the symptoms and prognosis in RA patients.  It is well recognized that RA is related to both higher morbidity and mortality. Increased risk of cardiovascular disease (CVD) has been noted in various studies. Systemic inflammation contributes to the increased risk of accelerating the atherosclerotic process. Recent studies have shown that the treatment that reduces the systemic inflammation, such as TNF inhibitors, may decrease the cardiovascular risk. But, observational studies like these are all expected to have some remaining confounding by indication in spite of different efforts to overcome this. For example, comorbidities like heart failure, malignant disease, and severe infections establish a total or comparative contraindication for starting bDMARDs therapy. Before beginning treatment with bDMARDs, clinicians must consider other comorbidities and factors as bDMARDs may also result in an increased risk of opportunistic as well as other infections.

Rationale behind the research:

Real life data regarding how comorbidities are dispersed among patients treated or not treated with bDMARDs are limited.

Objective:

To examine the use of bDMARDs in patients with RA and to see whether demographics (age, sex), comorbidities and health care consumption differed between patients treated with or without bDMARDs.

Note: This is a cross-sectional population-based analysis

Study outcomes

Description and comparison of comorbid conditions and healthcare consumption in RA patients with or without bDMARD: Descriptive, comparative, univariate and multiple logistic regression analyses were used to identify factors associated with bDMARDs.

*ARTIS: Anti-rheumatic therapy in Sweden; the Swedish biologic register; VEGA: The regional healthcare database

Outcomes

• Description and comparison of comorbid conditions and health care consumption in RA patients with or without bDMARDs: Patients without bDMARDs included a higher proportion of older age males. In patients without bDMARDs, the incidence of most of the comorbid conditions was considerably higher than patients treated with bDMARDs. While on the other side, patients treated with bDMARDs had more infections. Patients without bDMARDs had longer hospitalizations as compared to patients treated with bDMARDs. Outpatient physician visits in secondary care were more common in patients treated with bDMARDs as compared to the patients without bDMARDs, whereas the opposite was noted for primary health care visits. In general, men had a higher occurrence of comorbid conditions than women, except depression, infections, and fractures. The RA diagnosis was found to be the leading cause of hospitalization in both RA patients with and without bDMARDs, and especially in the group treated with bDMARDs.
• Comorbid conditions and health care consumption associated with bDMARDs or not: Cerebrovascular and ischemic heart disease, heart failure, atrial fibrillation, chronic respiratory disease, chronic renal insufficiency, malignancy, and depression occurred more commonly in patients not treated with bDMARDs. However, the incidence of infections was more frequent in those treated with bDMARDs.

Data are expressed as number (%). n = number of hospitalizations

Table 1: The top ten primary discharge diagnoses in patients with and without bDMARDs

This cross-sectional analysis indicated the difference between RA patients with and without bDMARDs concerning age, comorbid pattern and health care consumption. RA patients treated with bDMARDs were younger, had less comorbid conditions, and consumed more secondary outpatient care, but less primary outpatient care.

Also, the older age and higher period occurrence of other comorbid conditions in patients not treated with bDMARDs may suggest an increased fragility, which may have to lead the clinicians to avoid bDMARDs in these patients. Some previous studies have also shown similar results, lower use of bDMARDs in old patients and that RA patients with less comorbidity were more likely to be treated with bDMARDs. The present study noted infections linked with bDMARDs, which is in concordance with earlier studies that have shown an increased risk of infections in patients with bDMARDs. It is suggested from this study that clinicians must consider the difference in comorbidities between RA patients with or without bDMARDs while evaluating efficacy and safety of bDMARDs in ordinary care.