Baseline demographics and clinical characteristics* for patients with newly diagnosed SLE by disease severity
| Variable | All patients (N=2227) | SLE disease severity† | P value | ||
| Mild (n=586) | Moderate (n=1135) | Severe (n=506) | |||
| Demographics | |||||
| Age, mean years (SD) | 50.2 (13.0) | 50.0 (12.2) | 49.7 (13.1) | 51.8 (13.3) | 0.0088 |
| Age category, n (%) | |||||
| 18–44 years | 709 (31.8) | 187 (31.9) | 373 (32.9) | 149 (29.4) | 0.0298 |
| 45–64 years | 1252 (56.2) | 336 (57.3) | 640 (56.4) | 276 (54.5) | |
| ≥65 years | 266 (11.9) | 63 (10.8) | 122 (10.7) | 81 (16.0) | |
| Female, n (%) | 2017 (90.6) | 544 (92.8) | 1030 (90.7) | 443 (87.5) | 0.0113 |
| Race/ethnicity, n (%) | |||||
| Non-Hispanic white | 1212 (54.4) | 318 (54.3) | 621 (54.7) | 273 (54.0) | 0.2913 |
| Non-Hispanic black | 298 (13.4) | 87 (14.8) | 136 (12.0) | 75 (14.8) | |
| Hispanic | 105 (4.7) | 25 (4.3) | 61 (5.4) | 19 (3.8) | |
| Other | 124 (5.6) | 40 (6.8) | 58 (5.1) | 26 (5.1) | |
| Unknown | 488 (21.9) | 116 (19.8) | 259 (22.8) | 113 (22.3) | |
| Region, n (%) | |||||
| Northeast | 415 (18.6) | 92 (15.7) | 211 (18.6) | 112 (22.1) | 0.0517 |
| North central | 289 (13.0) | 75 (12.8) | 139 (12.2) | 75 (14.8) | |
| South | 1303 (58.5) | 354 (60.4) | 681 (60.0) | 268 (53.0) | |
| West | 210 (9.4) | 64 (10.9) | 97 (8.5) | 49 (9.7) | |
| Unknown | 10 (0.4) | 1 (0.2) | 7 (0.6) | 2 (0.4) | |
| Health plan type, n (%) | |||||
| HMO | 219 (9.8) | 60 (10.2) | 114 (10.0) | 45 (8.9) | 0.0873 |
| Indemnity | 169 (7.6) | 43 (7.3) | 74 (6.5) | 52 (10.3) | |
| POS | 244 (11.0) | 73 (12.5) | 119 (10.5) | 52 (10.3) | |
| PPO | 1367 (61.4) | 355 (60.6) | 719 (63.3) | 293 (57.9) | |
| Other | 164 (7.4) | 40 (6.8) | 82 (7.2) | 42 (8.3) | |
| Unknown | 64 (2.9) | 15 (2.6) | 27 (2.4) | 22 (4.3) | |
| Payer type, n (%) | |||||
| Commercial | 1953 (87.7) | 521 (88.9) | 1008 (88.8) | 424 (83.8) | 0.0098 |
| Medicare supplemental | 274 (12.3) | 65 (11.1) | 127 (11.2) | 82 (16.2) | |
| Clinical characteristics | |||||
| Medication use, n (%) | |||||
| Opioids | 1199 (53.8) | 248 (42.3) | 649 (57.2) | 302 (59.7) | <0.0001 |
| Antidepressants | 784 (35.2) | 173 (29.5) | 420 (37.0) | 191 (37.7) | 0.0034 |
| Muscle relaxants | 523 (23.5) | 111 (18.9) | 294 (25.9) | 118 (23.3) | 0.0054 |
| Sedatives | 508 (22.8) | 106 (18.1) | 254 (22.4) | 148 (29.2) | <0.0001 |
| Gabapentin | 189 (8.5) | 23 (3.9) | 116 (10.2) | 50 (9.9) | <0.0001 |
| Antimigraine | 133 (6.0) | 23 (3.9) | 86 (7.6) | 24 (4.7) | 0.0042 |
| CCI, mean (SD) | 1.2 (1.5) | 0.8 (1.1) | 1.1 (1.4) | 1.8 (1.8) | <0.0001 |
| CCI category, n (%) | |||||
| 0 | 895 (40.2) | 301 (51.4) | 461 (40.6) | 133 (26.3) | <0.0001 |
| 1 | 664 (29.8) | 177 (30.2) | 345 (30.4) | 142 (28.1) | |
| 2 | 341 (15.3) | 72 (12.3) | 172 (15.2) | 97 (19.2) | |
| ≥3 | 327 (14.7) | 36 (6.1) | 157 (13.8) | 134 (26.5) | |
| Individual comorbidities from the CCI, n (%) | |||||
| Diabetes mellitus | 298 (13.4) | 50 (8.5) | 147 (13.0) | 101 (20.0) | <0.0001 |
| Cerebrovascular accident | 140 (6.3) | 15 (2.6) | 44 (3.9) | 81 (16.0) | <0.0001 |
| Liver disease | 142 (6.4) | 23 (3.9) | 69 (6.1) | 50 (9.9) | 0.0003 |
| Any malignancy | 135 (6.1) | 28 (4.8) | 68 (6.0) | 39 (7.7) | 0.1280 |
| Peripheral vascular disease | 106 (4.8) | 13 (2.2) | 53 (4.7) | 40 (7.9) | <0.0001 |
| Congestive heart failure | 85 (3.8) | 12 (2.0) | 38 (3.3) | 35 (6.9) | <0.0001 |
| Myocardial infarction | 22 (1.0) | 0 (0.0) | 11 (1.0) | 11 (2.2) | 0.0014 |
| Metastatic disease | 13 (0.6) | 4 (0.7) | 5 (0.4) | 4 (0.8) | 0.5793 |
| Severe liver disease | 2 (0.1) | 0 (0.0) | 2 (0.2) | 0 (0.0) | 0.7317 |
| AIDS | 3 (0.1) | 1 (0.2) | 1 (0.1) | 1 (0.2) | 0.7949 |
| Other SLE-related comorbidities not included in the CCI,‡ n (%) | |||||
| Hypertension | 897 (40.3) | 195 (33.3) | 450 (39.6) | 252 (49.8) | <0.0001 |
| Infections | 759 (34.1) | 176 (30.0) | 385 (33.9) | 198 (39.1) | 0.0066 |
| Rheumatoid arthritis | 522 (23.4) | 126 (21.5) | 285 (25.1) | 111 (21.9) | 0.1630 |
| Myositis | 506 (22.7) | 112 (19.1) | 281 (24.8) | 113 (22.3) | 0.0292 |
| Anaemia | 451 (20.3) | 73 (12.5) | 230 (20.3) | 148 (29.2) | <0.0001 |
| Depression | 347 (15.6) | 78 (13.3) | 173 (15.2) | 96 (19.0) | 0.0330 |
| Anxiety | 273 (12.3) | 50 (8.5) | 140 (12.3) | 83 (16.4) | 0.0004 |
| Rash | 262 (11.8) | 64 (10.9) | 125 (11.0) | 73 (14.4) | 0.1068 |
| Sjögren’s syndrome | 194 (8.7) | 56 (9.6) | 86 (7.6) | 52 (10.3) | 0.1408 |
| Pleuritis | 165 (7.4) | 26 (4.4) | 81 (7.1) | 58 (11.5) | <0.0001 |
| Osteoporosis | 140 (6.3) | 27 (4.6) | 81 (7.1) | 32 (6.3) | 0.1226 |
| Chronic renal failure | 122 (5.5) | 4 (0.7) | 62 (5.5) | 56 (11.1) | <0.0001 |
| Raynaud’s syndrome | 118 (5.3) | 30 (5.1) | 65 (5.7) | 23 (4.5) | 0.5992 |
| Alopecia | 80 (3.6) | 25 (4.3) | 38 (3.3) | 17 (3.4) | 0.5936 |
| Nephritis | 78 (3.5) | 9 (1.5) | 35 (3.1) | 34 (6.7) | <0.0001 |
| Thrombocytopenia | 56 (2.5) | 11 (1.9) | 25 (2.2) | 20 (4.0) | 0.0581 |
| Pulmonary fibrosis | 56 (2.5) | 11 (1.9) | 25 (2.2) | 20 (4.0) | 0.0581 |
| Pulmonary hypertension | 45 (2.0) | 8 (1.4) | 19 (1.7) | 18 (3.6) | 0.0184 |
*During the 1-year period before diagnosis.
†Disease severity was assessed during the 1-year period after diagnosis, and patients were classified to the most severe level during that period.
‡SLE-related non-CCI comorbidity reported if ≥2% among all patients.
CCI, Charlson Comorbidity Index; HMO, health maintenance organisation; POS, point of service; PPO, preferred provider organisation.