Risk of preventable hospitalization before and after diagnosis among rheumatoid arthritis patients compared to non-rheumatoid arthritis controls.

OBJECTIVE

The purpose of the study is to investigate the risk of preventable hospitalization among patients with rheumatoid arthritis (RA).

METHODS

We identified 11,852 incident RA patients and 59,260 age-, sex-, and index year-matched controls from the Taiwan National Health Insurance Database. Index date was the RA diagnosis date for cases, which was assigned to their matched controls. The odds ratios (OR) of preventable hospitalizations between RA patients and controls were estimated using a mixed effect model adjusted for age, sex, patient characteristics, Elixhauser comorbidity index, medical utilization and regional medical resources.

RESULTS

The overall annualized incidence of preventable hospitalization in RA patients and controls was 38.7 vs. 20.9 events per 1,000 person-years (adjusted OR, 1.61; 95% confidence interval [CI], 1.51-1.71). The adjusted OR of preventable hospitalization in RA patients compared to matched controls was 1.17 (1.00-1.37) one year prior to RA diagnosis and remained elevated after RA diagnosis. Adjusted ORs (95% CI) for specific preventable hospitalization categories were 1.93 (1.58-2.36) for chronic obstructive pulmonary disease, 1.64 (1.21-2.21) for asthma, 1.95 (1.78-2.13) for bacterial pneumonia, and 1.59 (1.44-1.75) for urinary tract infection. When assessing the trend of individual preventable hospitalizations before and after diagnosis, bacterial pneumonia and urinary tract infection hospitalizations had a significantly higher OR in RA patients one year before diagnosis and five years afterward (adjusted OR ranges 2.75 to 4.48 and 1.83 to 3.07 respectively, all P-values<0.05)

CONCLUSION

RA is independently associated with a higher risk of preventable hospitalization specifically for chronic lung diseases and infections.