Table 2: Annualized healthcare utilization in the followup period for SLE patients and their matched controls.

SLE patientsNon-SLE patientsDifferenceP value
N = 14,262N = 14,262

Number of patients with at least 1 inpatient admission during the entire followup (N, %) 8,459 59.3%5,644 39.6%20%<0.001
Among those with at least 1 IP admission, number of inpatient admissions (mean, SD) 1.2 1.6 1.0 1.3 0.2 <0.001
Number of inpatient admissions among all patients (mean, SD) 0.7 1.3 0.4 1.00.3 <0.001
Number of patients with at least 1 ER visit during the entire followup (N, %) 11,202 78.5% 9,494 67.5%11%<0.001
Among those with at least 1 ER visit, number of ER visits (mean, SD) 2.6 4.7 2.1 3.5 0.6 <0.001
Number of ER visits among all patients (mean, SD)2.14.31.42.90.7<0.001
Number of physician office visits (mean, SD) 9.8 8.26.4 7.03.4 <0.001
Number of outpatient hospital visits (mean, SD) 3.3 5.8 2.2 5.01.1 <0.001
Number of other outpatient services (mean, SD) 69.7 86.8 56.8 89.812.9 <0.001

N: number, IP: inpatient admission, ER: emergency room.