Preventable Acute Care Use in Rheumatoid Arthritis: Evidence Synthesis and Consensus-Defined Ambulatory Care Sensitive Conditions

Background: Ambulatory care sensitive conditions (ACSCs) are widely used to assess health system performance in the general population, yet their relevance for RA has not been clearly established. This thesis sought to synthesize the existing evidence on contemporary acute care use by RA cohorts and to determine conditions that may inform disease-specific surveillance and intervention at the population level. Methods: Three complementary studies were conducted, two large scale systematic reviews and a Delphi consensus study involving clinician and patient experts over 5 rounds of voting. Results: Estimates of the frequency of all-cause acute care use were 1.5 to 3.5 times higher in RA cohorts compared to matched non-RA controls. Infections were the most frequently studied reason for hospitalization (38%), followed by cardiac (33%) and musculoskeletal conditions (21%). Congruently, pneumonia, stroke/transient ischemic attack, and RA flares were leading causes of hospitalization (1.7-45.8, 0.9-89.6, and 12.0-33.0 per 1,000 person-years respectively). Clinician and patient experts identified 13 conditions as proposed RA-specific ACSCs: those specific to RA disease activity (RA disease flare, vasculitis), RA-related associations and complications (anemia/pancytopenia, osteoporotic fracture, secondary osteoarthritis, cervical spine instability), as well as acute (upper respiratory infection, influenza/pneumonia, septic arthritis) and opportunistic infections (herpes zoster, tuberculosis reactivation, pneumocystis jirovecii pneumonia, and other). Conclusions: Acute care utilization in RA cohorts persists despite impressive treatment advances and likely increasingly reflects interactions of comorbidity, treatment-related adverse events, and residual inflammation. Proposed RA-specific ACSCs may support population-level monitoring of access to and quality of RA care, though more research is needed to evaluate their performance and utility.