Table 1.
Characteristics of rheumatoid arthritis (RA) and non-RA patients
| RA (overall) | Non-RA | RA (incident) | Non-RA | |
|---|---|---|---|---|
| N | 138,891 | 138,891 | 30,562 | 30,562 |
| Age, years | 55.6 (13.3) | 55.6 (13.3) | 54.5 (13.5) | 54.5 (13.5) |
| Female sex, % | 106,254 (76.5) | 106,254 (76.5) | 22,649 (74.1) | 22,649 (74.1) |
| Year of entrya, % | ||||
| 2006 | 43,543 (31.4) | 43,543 (31.4) | 12,636 (41.4) | 12,636 (41.4) |
| 2007 | 11,858 (8.5) | 11,858 (8.5) | 2,916 (9.5) | 2,916 (9.5) |
| 2008 | 25,187 (18.1) | 25,187 (18.1) | 5,903 (19.3) | 5,903 (19.3) |
| 2009 | 17,284 (12.4) | 17,284 (12.4) | 3,596 (11.8) | 3,596 (11.8) |
| 2010 | 16,569 (11.9) | 16,569 (11.9) | 2,994 (9.8) | 2,994 (9.8) |
| 2011 | 11,624 (8.4) | 11,624 (8.4) | 1,653 (5.4) | 1,653 (5.4) |
| 2012 | 7,589 (5.5) | 7,589 (5.5) | 616 (2.0) | 616 (2.0) |
| 2013 | 5,237(3.8) | 5,237(3.8) | 248 (0.8) | 248 (0.8) |
| Time from entry to index date, years | 1.5 (1.7) | 1.5 (1.7) | 3.5 (1.8) | 3.5 (1.8) |
| U.S. region, % | ||||
| Northeast | 23,393 (16.8) | 23,487 (16.9) | 4,806 (15.7) | 4,517 (14.8) |
| North Central | 29,559 (21.3) | 31,941 (23.0) | 6,007 (19.7) | 6,435 (21.1) |
| South | 62,618 (45.1) | 53,884 (38.8) | 14,732 (48.2) | 12,854 (42.1) |
| West | 21,280 (15.3) | 25,669 (18.5) | 4,707 (15.4) | 6,488 (21.2) |
| Unknown | 2,041 (1.5) | 3,910 (2.8) | 310 (1.0) | 268 (0.9) |
| RA medicationsb, % | ||||
| Methotrexate | 86,895 (62.6) | 530 (0.4) | 20,230 (66.2) | 172 (0.6) |
| Hydroxychloroquine | 42,288 (30.5) | 629 (0.5) | 11,252 (36.8) | 234 (0.8) |
| Sulfasalazine | 11,545 (8.3) | 176 (0.1) | 2,879 (9.4) | 69 (0.2) |
| Leflunomide | 13,611 (9.8) | 60 (0.04) | 1,892 (6.2) | 19 (0.06) |
| b/tsDMARDs | 34,177 (24.6) | 265 (0.2) | 3,070 (10.1) | 84 (0.3) |
Values mean (standard deviation) or n (%) of variables at the index date
Abbreviations: RA, rheumatoid arthritis; b/tsDMARDs, biologic or targeted synthetic disease-modifying anti-rheumatic drugs
a
year entering the database during study window
b
RA medications received prior to, or on, the index date