Table 1 Demographics and health characteristics of the study population. * data missing in some cases
| Variable | RA Group N = 126 | Control group N = 249 | P value |
|---|---|---|---|
| Female % | 70% | 56% | 0.009 |
| Age, mean (SD) | 70 (6.6) | 70 (7.1) | 0.39 |
| Smoking habit % | N = 234* | 0.58 | |
| Current/past smokers N (%) | 78 (61.9%) | 140 (59.8%) | |
| Socio-economic status (SES) | |||
| White collar | 47.6% | 54.2% | 0.75 |
| Blue collar | 52.4% | 45.8% | |
| BMI, mean (SD) | 27 (5.1) | 23 (3.7) | 0.000 |
| Diabetes (including both type I and II) N (%) | 17 (13.5%) | 20 (8.1%) | 0.10 |
| Interstitial lung disease N(%) | 5 (4.0%) | 0 (N = 240*) | 0.002 |
| Angina pectoris N (%) | 15 (11.9%) | 26 (10.5%) N = 247* | 0.69 |
| Myocardial infarct N (%) | 10 (7.9%) | 15 (6.0%) N = 248* | 0.49 |
| Stroke N (%) | 11 (8.7) % | 10 (4.0%) N = 248* | 0.06 |