Table 1.

Baseline characteristics of CKD-free patients with rheumatoid arthritis by use of hydroxychloroquine within 90 days after rheumatoid arthritis diagnosis

CharacteristicaHydroxychloroquine Nonusers, n=1407Hydroxychloroquine Users, n=1212
Demographics
 Age, yr51±1452±14
 Men342 (24%)290 (24%)
 Monthly income, new Taiwan dollars18,838±15,98217,689±14,610
 Geographic location
  Northern Taiwanb721 (51%)554 (46%)
  Central Taiwanb277 (20%)320 (26%)
  Southern Taiwan371 (26%)311 (26%)
  Eastern Taiwan and islands38 (3%)27 (2%)
 Clinic visit frequency, visits per yearb26±1627±15
Comorbidities
 Charlson comorbidity index score1.2±1.41.2±1.4
 Hypertension305 (22%)274 (23%)
 Hyperlipidemia183 (13%)146 (12%)
 Diabetes mellitus106 (8%)81 (7%)
 Coronary artery disease107 (8%)84 (7%)
 Congestive heart failure33 (2%)20 (2%)
 Goutb214 (15%)131 (11%)
 Stroke51 (4%)53 (4%)
 Chronic obstructive pulmonary disease146 (10%)111 (9%)
 Peripheral artery occlusive disease11 (0.8%)15 (1%)
 Arrhythmia65 (5%)41 (3%)
Baseline long-term medications
 Antidiabetic drugs63 (4%)64 (5%)
 Antihypertensive drugs244 (17%)220 (18%)
  Angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers103 (7%)94 (8%)
  Diuretics71 (5%)65 (5%)
 Nonsteroidal anti-inflammatory drugs160 (11%)138 (11%)
 Analgesic drugs other than nonsteroidal anti-inflammatory drugsc133 (9%)137 (11%)
 Glucocorticoidsb89 (6%)149 (12%)
 Calcineurin inhibitorsd1 (0.1%)3 (0.3%)
 TNF-α inhibitorsb86 (6%)116 (10%)
 Other immunosuppressantse72 (5%)66 (5%)
Cumulative dose of hydroxychloroquine within 90 d, g43.2±24.8
Propensity scoreb0.45±0.090.48±0.10
  • —, not applicable.

  • a Variables are expressed as mean±SD or n (%).

  • b Statistically significant.

  • c Includes cyclooxygenase-2 inhibitors, aspirin, and acetaminophen.

  • d Includes cyclosporin and tacrolimus.

  • e Includes methotrexate, leflunomide, sulfasalazine, and azathioprine.