Table 3.
HCRU incidence rates during the 12‐month observation period for the OCS‐initiator cohort exposure categories and the no‐OCS‐use cohort (N = 27,352)
| All‐cause HCRU, n (%) | Incidence per person‐year | Adjusted IRR (95% CI) a vs. the no‐OCS‐use cohort | P value | |
|---|---|---|---|---|
| No OCS use (n = 11,136) | ||||
| Any visits | 10,917 (98.0) | 25.03 | — | — |
| Outpatient | 10,880 (97.7) | 20.38 | — | — |
| Inpatient | 1367 (12.3) | 0.19 | — | — |
| Emergency department | 2305 (20.7) | 0.47 | — | — |
| Other b | 2856 (25.6) | 3.99 | — | — |
| No 6‐month periods of OCS use >5 mg/day (n = 11,438) | ||||
| Any visits | 11,410 (99.8) | 29.95 | 1.22 (1.19‐1.24) | <0.01 |
| Outpatient | 11,386 (99.5) | 24.74 | 1.23 (1.20‐1.25) | <0.01 |
| Inpatient | 1904 (16.6) | 0.26 | 1.43 (1.33‐1.53) | <0.01 |
| Emergency department | 3430 (30.0) | 0.86 | 1.74 (1.63‐1.85) | <0.01 |
| Other b | 3229 (28.2) | 4.08 | 1.07 (0.98‐1.17) | 0.12 |
| One 6‐month period of OCS use >5 mg/day (n = 3048) | ||||
| Any visits | 3044 (99.9) | 38.84 | 1.39 (1.34‐1.43) | <0.01 |
| Outpatient | 3040 (99.7) | 31.49 | 1.42 (1.38‐1.46) | <0.01 |
| Inpatient | 1114 (36.5) | 0.65 | 2.65 (2.42‐2.90) | <0.01 |
| Emergency department | 874 (28.7) | 0.82 | 1.42 (1.29‐1.56) | <0.01 |
| Other b | 999 (32.8) | 5.88 | 1.19 (1.04‐1.36) | 0.01 |
| Two 6‐month periods of OCS use >5 mg/day (n = 1730) | ||||
| Any visits | 1729 (99.9) | 47.28 | 1.66 (1.60‐1.73) | <0.01 |
| Outpatient | 1727 (99.8) | 36.07 | 1.61 (1.55‐1.68) | <0.01 |
| Inpatient | 779 (45.0) | 0.92 | 3.66 (3.30‐4.06) | <0.01 |
| Emergency department | 586 (33.9) | 1.07 | 1.71 (1.52‐1.93) | <0.01 |
| Other b | 655 (37.9) | 9.22 | 1.98 (1.67‐2.35) | <0.01 |
Note: One patient with unknown sex in the OCS nonuser cohort was excluded from the adjusted analyses.
Abbreviations: CI, confidence interval; HCRU, health care resource use; IRR, incidence rate ratio; OCS, oral corticosteroid.
IRRs and the respective 95% CIs and P values were calculated using generalized linear models with a negative binomial distribution and log link, controlling for the baseline covariates sex, age on index date, geographic region, baseline total health care costs, baseline Charlson Comorbidity Index, baseline use of prescription drugs, baseline disease severity, and baseline flares.
Including ambulance, assisted living facilities, comprehensive rehabilitation facilities, custodial care facilities, hospice/home care services, intermediate care facilities, psychiatric facilities, and skilled nursing facilities.