Table 1.
Baseline characteristics
| IA patients | Matched controls | |
|---|---|---|
| N (ratio 1:2) |
3,354 |
6,708 |
| Sex |
|
|
| Female |
63.7% |
63.7% |
| Age, years |
|
|
| Mean (sd) |
55 (15) |
55 (15) |
| Follow-up, years |
|
|
| Median (iqr) |
2.8 (1.7-4.9) |
2.7 (1.6-4.9) |
| Number of chronic diseases at inclusion* |
|
|
| Median (iqr) |
1 (0–3) |
1 (0–2) |
| Year of inclusion, |
|
|
| 2001 |
<1% |
<1% |
| 2002 |
16% |
16% |
| 2003 |
12% |
12% |
| 2004 |
9% |
9% |
| 2005 |
10% |
10% |
| 2006 |
10% |
10% |
| 2007 |
13% |
13% |
| 2008 |
11% |
11% |
| 2009 |
11% |
11% |
| 2010 | 9% | 9% |
IA = inflammatory arthritis sd= standard deviation, iqr=interquartile range, min= minimum, max=maximum.
*without IA.