Characteristics of the study population.
| Controls | PsA | P | |
|---|---|---|---|
| No. patients | 24,180 | 4836 | - |
| SLE cases | 36 (0.15) | 18 (0.37) | 0.001 |
| Age, yrs, mean ± SD | 56.25 ± 15.26 | 56.31 ± 15.24 | NS |
| Sex, female | 13,015 (53.8) | 2603 (53.8) | NS |
| SES | |||
| 1 | 9082 (40.6) | 1552 (32.2) | < 0.0001 |
| 2 | 8336 (37.3) | 1958 (40.7) | < 0.0001 |
| 3 | 4956 (22.2) | 1306 (27.1) | < 0.0001 |
| Smokers | 9220 (38.3) | 2051 (42.5) | < 0.0001 |
| Ethnicity | |||
| Arab | 4369 (18.5) | 612 (12.7) | < 0.0001 |
| Jewish | 19,296 (81.5) | 4224 (87.3) | |
| BMI, mean ± SD | 27.47 ± 5.44 | 28.65 ± 5.80 | < 0.0001 |
| Comorbidity | |||
| Hyperlipidemia | 13,541 (56) | 3125 (64.6) | < 0.0001 |
| Hypertension | 8383 (34.7) | 2035 (42.1) | < 0.0001 |
| DM | 5339 (22.1) | 1353 (28) | < 0.0001 |
| Malignancy | 2709 (11.2) | 980 (20.3) | < 0.0001 |
| Osteoporosis | 2376 (9.8) | 623 (12.9) | < 0.0001 |
| Obesity | 6790 (28.1) | 1851 (38.3) | < 0.0001 |
| CHF | 758 (3.2) | 218 (4.5) | < 0.0001 |
| IHD | 3000 (12.4) | 766 (15.8) | < 0.0001 |
| CVA | 1312 (5.4) | 304 (6.3) | 0.017 |
| cDMARD | 578 (2.4) | 4090 (84.6) | < 0.0001 |
| bDMARD | |||
| Anti-TNF-α | 97 (0.4) | 1779 (36.8) | < 0.0001 |
| Possible SLE-inducing medication used prior to SLE diagnosis | |||
| Statins | 5 (0.02) | 7 (0.15) | 0.001 |
| PPI | 12 (0.05) | 5 (0.1) | NS |
| Beta blockers | 1 (0.004) | 2 (0.04) | 0.07 |
| ACEi | 7 (0.03) | 1 (0.02) | NS |
| Thiazides | 7 (0.03) | 1 (0.02) | NS |
| Anti-TNF-α | 0 (0.0) | 2 (0.04) | 0.028 |
Values are n (%) unless otherwise specified. The percentages reported were calculated from the actual number, not including missing data. ACEi: angiotensin-converting enzyme inhibitor; anti-TNF-α: anti–tumor necrosis factor-α; bDMARD: biological disease-modifying antirheumatic drug; cDMARD: conventional disease-modifying antirheumatic drug; CHF: congestive heart failure; CVA: cerebrovascular accident; DM: diabetes mellitus; IHD: ischemic heart disease; NS: not significant; PPI: proton pump inhibitor; PsA: psoriatic arthritis; SES: socioeconomic status; SLE: systemic lupus erythematosus.