Table 3.
Evaluation of the association of patient characteristics with QTc length
| SLE (n=50) |
RA (n=139) |
|||
|---|---|---|---|---|
| Parameter estimate | p Value | Parameter estimate | p Value | |
| Age, years | 0.37 | 0.41 | 0.38 | 0.25 |
| Female sex | 19.7 | 0.35 | 12.2 | 0.03 |
| Race/ethnicity | ||||
| White | −39.5 | 0.17 | −2.8 | 0.73 |
| Hispanic | −13.5 | 0.32 | 14.2 | 0.67 |
| Black | 24.8 | 0.09 | 14.2 | 0.67 |
| Disease duration, years | 0.39 | 0.70 | −0.32 | 0.31 |
| SLEDAI-2K | −0.38 | 0.69 | – | – |
| Lupus nephritis | −11.8 | 0.31 | – | – |
| APS | −0.62 | 0.98 | – | – |
| Moderate–severe disease activity* | −3.8 | 0.75 | 5.3 | 0.36 |
| DAS28-CRP | – | – | 3.2 | 0.24 |
| CRP, mg/L | −0.03† | 0.74 | 0.45 | 0.046 |
| IL-6, pg/mL | – | – | 0.68 | 0.23 |
| Antimalarials | 3.6 | 0.76 | −0.15 | 0.98 |
| MMF | −3.4 | 0.77 | – | – |
| AZA | 34.5 | 0.07 | – | – |
| Non-biologic DMARD | – | – | −7.8 | 0.32 |
| Biologic DMARD | – | – | −3.9 | 0.49 |
| Glucocorticoids | −2.6 | 0.82 | −0.7 | 0.90 |
| ds-DNA antibody | 12.8 | 0.39 | – | – |
| SSA/anti-Ro | 1.56 | 0.90 | – | – |
| SSB/anti-La | −13.4 | 0.30 | – | – |
| Sm antibody | 2.6 | 0.83 | – | – |
| RNP antibody | −1.49 | 0.90 | – | – |
| RF>40 units | – | – | −0.50 | 0.93 |
| Anti-CCP>60 units | – | – | 0.80 | 0.89 |
| Hypertension | −0.92 | 0.94 | 15.9 | 0.14 |
| Diabetes | −3.1 | 0.90 | 3.1 | 0.59 |
| Current smoking | −0.88 | 0.94 | 6.7 | 0.49 |
| Aspirin | −10.0 | 0.52 | −7.3 | 0.22 |
| Statin | −25.9 | 0.17 | 8.8 | 0.2 |
| QT-modifying medications | 18.2 | 0.14 | −4.9 | 0.51 |
| Muscle relaxant, n (%) | −8.1 | 0.84 | 8.2 | 0.50 |
| Antipsychotics, n (%) | −28.0 | 0.34 | 0 | 0 |
| Antidepressants, n (%) | 18.6 | 0.19 | −7.6 | 0.31 |
| Antimicrobials‡, n (%) | −35.6 | 0.39 | 9.8 | 0.68 |
| Antiemetics, n (%) | −1.5 | 0.94 | −8.0 | 0.68 |
| ST-T abnormalities | −4.0 | 0.73 | 9.3 | 0.21 |
Univariable linear regression parameter estimates and corresponding p values of the association of QTc duration with each listed variable.
*Moderate–severe disease activity is defined as SLEDAI-2K >6 or DAS28 CRP >3.2.
†n=40.
‡Antimicrobials include macrolides, fluoroquinolones and HIV retrovirals.
Anti-CCP, anticitrullinated cyclic peptide; APS, antiphospholipid antibody syndrome; AZA, azathioprine; CRP, C reactive protein; DAS28, Disease Activity Score in 28 joints; DMARD, disease-modifying antirheumatic drug; IL-6, interleukin 6; MMF, mycophenolate mofetil; QTc, corrected QT-interval; RA, rheumatoid arthritis; RF, rheumatoid factor; SLE, systemic lupus erythematosus; SLEDAI-2K, Systemic Lupus Erythematosus Disease Activity Index 2000.