Generalized linear model of annual costs (2003–2008).
| Factor | Cost Ratio | (95% CI) | p |
|---|---|---|---|
| SSc (control patients as Ref.) | 1.988 | (1.773–2.230) | < 0.001 |
| Year (2003 as Ref.) | |||
| 2004 | 1.100 | (0.954–1.268) | 0.191 |
| 2005 | 1.075 | (0.927–1.247) | 0.339 |
| 2006 | 1.161 | (1.002–1.346) | 0.046 |
| 2007 | 1.083 | (0.943–1.245) | 0.260 |
| 2008 | 1.129 | (0.985–1.295) | 0.082 |
| Age (18–44 yrs as Ref.) | |||
| 45–64 | 1.317 | (1.200–1.444) | < 0.001 |
| > 65 | 1.013 | (0.889–1.154) | 0.849 |
| Male (female as Ref.) | 0.861 | (0.749–0.989) | 0.035 |
| Geographic region (South as Ref.) | |||
| Midwest | 1.116 | (0.952–1.307) | 0.175 |
| Northeast | 0.959 | (0.875–1.052) | 0.379 |
| West | 0.972 | (0.864–1.092) | 0.626 |
| Organ involvement (post-index) | |||
| Raynaud’s syndrome | 0.948 | (0.831–1.082) | 0.427 |
| Lung disease | 2.298 | (2.021–2.614) | < 0.001 |
| Pulmonary hypertension | 0.907 | (0.743–1.107) | 0.335 |
| GI bleeding | 1.894 | (1.577–2.273) | < 0.001 |
| Renal disease | 3.074 | (2.406–3.927) | < 0.001 |
| Medications | |||
| Methotrexate | 1.263 | (1.021–1.562) | 0.032 |
| Systemic corticosteroids | 1.650 | (1.484–1.834) | < 0.001 |
| PAH drugs (Bosentan, Ambrisentan, epoprostenol, treprostinil, sildenafil) | 2.599 | (1.969–3.430) | < 0.001 |
| Mean predicted costs, US $ | |||
| SSc patients | 18,395.66 | ||
| Controls | 5,316.05 |
GI: gastrointestinal; PAH: pulmonary arterial hypertension; SSc: systemic sclerosis.