Undetectable mannose binding lectin is associated with HRCT proven bronchiectasis in rheumatoid arthritis (RA)

Prevalence and risk factors of bronchiectasis in rheumatoid arthritis: A systematic review and meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis for the prevalence and risk factors of rheumatoid arthritis-related bronchiectasis (RA-BR).

METHODS

We queried PubMed and EMBASE databases to identify published literature related to prevalence and risk factors for RA-BR among patients with RA. Data extraction included study design, country, year, method of RA-BR detection, RA characteristics, numerator of RA-BR cases and denominator of patients with RA, and associations with RA-BR presence. We performed a meta-analysis using random or fixed effects models to estimate the prevalence of RA-BR among RA.

RESULTS

Out of a total of 253 studies, we identified 41 total studies that reported on prevalence (n = 34), risk factors (n = 5), or both (n = 2). The included studies had heterogeneous methods to identify RA-BR. Among the 36 studies reporting prevalence, 608 RA-BR cases were identified from a total of 8569 patients with RA. In the meta-analysis, the pooled overall prevalence of RA-BR among RA was 18.7% (95%CI 13.7-24.3%) using random effects and 3.8% (95%CI 3.3-4.2%) using fixed effects. Among studies that used high-resolution chest computed tomography (HRCT) imaging, the prevalence of RA-BR was 22.6% (95%CI 16.8-29.0%) using random effects. When only considering retrospective studies (n = 12), the pooled prevalence of RA-BR among RA was 15.5% (95%CI 7.5-25.5%); among prospective studies (n = 24), the pooled prevalence was 20.7% (95% CI 14.7-27.4%). Risk factors for RA-BR included older age, longer RA duration, genetics (CFTR and HLA), and undetectable circulating mannose binding lectin (MBL) as a biomarker.

CONCLUSION

In this systematic review and meta-analysis, the prevalence of RA-BR was nearly 20% among studies with HRCT imaging, suggesting that bronchiectasis may be a common extra-articular feature of RA. Relatively few factors have been associated with RA-BR. Future studies should standardize methods to identify RA-BR cases and investigate the natural history and clinical course given the relatively high prevalence among RA.

Bronchiectasis Exacerbations: Definitions, Causes, and Acute Management

Pulmonary exacerbations (PExs) are events in the course of bronchiectasis which are defined as an increase in disease symptoms lasting a period of a few days. It is established that the tendency toward having PEx is stable throughout the course of the disease. Certain conditions were found to be associated with an increased risk of developing a PEx. Among these are chronic airway infection with Pseudomonas aeruginosa or Aspergillus species, concomitant airway diseases (asthma, chronic obstructive pulmonary disease, and chronic rhinosinusitis), genetic factors such as primary ciliary dyskinesia, and nutritional factors. The immediate events underlying the onset of a PEx are less clearly determined. Although acute changes in bacterial airway composition have been the paradigm for decades, recent microbiome-focused research has not uniformly established such acute changes at the onset of PEx. Other acute changes such as air pollution, viral infection, and changes in bacterial metabolic activity have also been implicated as causes of a PEx. Despite these gaps in our knowledge of the biology of PEx, antimicrobial therapy directed against the identified pathogens in sputum is currently the recommended therapeutic strategy. Various long-term therapies, including antimicrobial and anti-inflammatory strategies, have been proven effective in reducing the frequency of PEx, leading to a recommendation for the use of these strategies in people with frequent PEx.