Characteristics of included incident cases of SLE, identified from the CPRD between 1 January 2000 and 31 December 2012, stratified by disease severity at diagnosis
| Disease severity at diagnosis | |||
|---|---|---|---|
| Mild-to-moderate (n=1070) | Severe (n=356) | All (n=1426) | |
| Patient characteristics | |||
| Males, n (%) | 932 (74.2) | 324 (25.8) | 1256 (88.1) |
| Females, n (%) | 105 (61.8) | 65 (38.2) | 170 (11.9) |
| Mean age at SLE diagnosis (years, SD) | 48.3 (17.0) | 46.6 (18.7) | 47.9 (17.4) |
| Age at diagnosis, n (%) | |||
| 0–9 years | 5 (0.5) | 2 (0.6) | 7 (0.5) |
| 10–19 years | 45 (4.2) | 40 (11.2) | 85 (6.0) |
| 20–29 years | 92 (8.6) | 28 (7.9) | 120 (8.4) |
| 30–39 years | 190 (17.8) | 60 (16.9) | 250 (17.5) |
| 40–49 years | 251 (23.5) | 58 (16.3) | 309 (21.7) |
| 50–59 years | 200 (18.7) | 70 (19.7) | 270 (18.9) |
| 60–69 years | 144 (13.5) | 51 (14.3) | 195 (13.7) |
| 70–79 years | 116 (10.8) | 42 (11.8) | 158 (11.1) |
| ≥80 years | 27 (2.5) | 5 (1.4) | 32 (2.2) |
| Supporting evidence of SLE diagnosis, n (%) | |||
| Evidence of hospital treatment for SLE | 624 (58.3) | 231 (64.9) | 855 (60.0) |
| Antimalarial prescribing after diagnosis | 790 (72.5) | 242 (68.0) | 1032 (72.4) |
| Oral prednisolone (minimum 3 months) after diagnosis | 257 (24.0) | 318 (89.3) | 575 (40.3) |
| Immunosuppressant prescribing after diagnosis | 127 (11.9) | 227 (63.8) | 354 (24.8) |
| NSAID prescribing (minimum three prescriptions) | 609 (56.9) | 177 (49.7) | 786 (55.1) |
| Therapy for refractory cutaneous LE after diagnosis | 63 (5.9) | 20 (5.6) | 83 (5.8) |
| Evidence of severe systemic involvement at any time after diagnosis | 13 (1.2) | 22 (6.2) | 35 (2.5) |
| Four or more ACR criteria28 29 | 56 (5.2) | 28 (7.9) | 84 (5.9) |
| Four or more SLICC criteria43 | 73 (6.8) | 43 (12.1) | 116 (8.1) |
Disease severity at baseline is defined as severe if the patient had at least one prescription for an immunosuppressant or a prescription for at least 30 days of treatment with oral prednisolone at a dose of 7.5 mg/day or more within 12 months of date of SLE diagnosis. All remaining patients were classified as having mild-to-moderate disease.
ACR, American College of Rheumatology; CPRD, Clinical Practice Research Database; LE, lupus erythematosus; NSAID, non-steroidal anti-inflammatory drugs; SLICC, Systemic Lupus International Collaborating Clinics.