Table 2 Initial hydroxychloroquine prescription dose in relation to dosing recommendations
Characteristics | Dose > 6.5 mg/kg/day, ideal body weight (prior recommendation) | Dose > 5 mg/kg/day, actual body weight (latest recommendation) | ||||
|---|---|---|---|---|---|---|
Number (%) | Crude OR (95% CI) | Multivariablea OR (95% CI) | Number (%) | Crude OR (95% CI) | Multivariablea OR (95% CI) | |
Year of initial prescript | ||||||
 2007–2008 | 1099 (40) | 1.00 (Reference) | 1.00 (Reference) | 1055 (38) | 1.00 (Reference) | 1.00 (Reference) |
 2009–2010 | 1406 (39) | 0.98 (0.88–1.08) | 1.00 (0.89–1.11) | 1348 (38) | 0.97 (0.88–1.08) | 0.99 (0.89–1.11) |
 2011–2012 | 1597 (38) | 0.92 0.83–1.02) | 0.95 (0.85–1.05) | 1519 (36) | 0.91 (0.82–1.00) | 0.92 0.83–1.03) |
 2013–2014 | 1511 (37) | 0.88 (0.80–0.97) | 0.90 (0.76–1.00) | 1408 (35) | 0.84 (0.76–0.93) | 0.88 (0.79–0.99) |
 2015–2016 | 1073 (36) | 0.84 (0.76–0.94) | 0.85 (0.76–0.95) | 901 (30) | 0.70 (0.62–0.78) | 0.76 (0.68–0.86) |
Sex | ||||||
 Male | 268 (7) | 1.00 (Reference) | 1.00 (Reference) | 998 (25) | 1.00 (Reference) | 1.00 (Reference) |
 Female | 6418 (47) | 11.71 (10.30–13.32) | 12.52 (10.99–14.26) | 5233 (38) | 1.76 (1.62–1.90) | 1.98 (1.81–2.15) |
Age | ||||||
  ≤ 55 years | 3647 (38) | 1.00 (Reference) | 1.00 (Reference) | 3453 (36) | 1.00 (Reference) | 1.00 (Reference) |
  > 55 years | 3039 (38) | 1.00 (0.94–1.08) | 1.23 (1.15–1.32) | 2778 (35) | 0.95 (0.89–1.01) | 1.18 (1.10–1.27) |
BMI (kg/m2) | ||||||
 Underweight (< 18.5) | 104 (28) | 0.74 (0.59–0.93) | 0.66 (0.52–0.84) | 176 (48) | 0.82 (0.66–1.01) | 0.78 (0.63–0.97) |
 Normal (18.5 – < 25) | 2114 (35) | 1.00 (Reference) | 1.00 (Reference) | 3215 (53) | 1.00 (Reference) | 1.00 (Reference) |
 Overweight (25 – < 30) | 2134 (36) | 1.07 (1.00–1.12) | 1.28 (1.19–1.39) | 2319 (39) | 0.58 (0.54–0.63) | 0.61 (0.57–0.66) |
 Obese (≥ 30) | 2334 (44) | 1.51 (1.40–1.63) | 1.61 (1.49–1.75) | 521 (10) | 0.10 (0.09–0.11) | 0.10 (0.09–0.11) |
Smoking | ||||||
 Current smoker | 1245 (36) | 0.89 (0.83–0.96) | 1.06 (0.98–1.16) | 1294 (37) | 1.10 (1.02–1.19) | 1.03 (0.95–1.13) |
 Non-smoker | 5426 (39) | 1.00 (Reference) | 1.00 (Reference) | 4924 (35) | 1.00 (Reference) | 1.00 (Reference) |
CKD | ||||||
 CKD stage > 3 | 516 (37) | 0.97 (0.86–1.08) | 0.88 (0.73–1.00) | 429 (31) | 0.81 (0.72–0.91) | 0.87 (0.76–0.99) |
 No CKD | 6170 (38.1) | 1.00 (Reference) | 1.00 (Reference) | 5802 (36) | 1.00 (Reference) | 1.00 (Reference) |
Diabetes | ||||||
 Yes | 726 (38) | 0.99 (0.90–1.09) | 1.05 (0.94–1.17) | 483 (25) | 0.58 (0.52–0.65) | 0.92 (0.81–1.03) |
 No | 5960 (38) | 1.00 (Reference) | 1.00 (Reference) | 5748 (37) | 1.00 (Reference) | 1.00 (Reference) |
Tamoxifen use | ||||||
 Yes | 113 (51) | 1.67 (1.29–2.18) | 1.16 (0.89–1.52) | 94 (42) | 1.32 (1.01–1.73) | 1.16 (0.87–1.55) |
 No | 6573 (38) | 1.00 (Reference) | 1.00 (Reference) | 6137 (35) | 1.00 (Reference) | 1.00 (Reference) |
Indication for HCQ | ||||||
 RA/inflammatory arthritis | 3651 (36) | 1.00 (Reference) | 1.00 (Reference) | 3491 (35) | 1.00 (Reference) | 1.00 (Reference) |
 SLE | 628 (37) | 1.03 (0.93–1.15) | 0.84 (0.75–0.94) | 590 (35) | 1.04 (0.93–1.17) | 0.87 (0.77–0.98) |
 SARD | 287 (43) | 1.34 (1.14–1.56) | 1.07 (0.91–1.26) | 272 (41) | 1.29 (1.10–1.51) | 1.09 (0.92–1.30) |
 Primary dermatologic disease | 745 (41) | 1.23 (1.11–1.36) | 1.11 (0.99–1.25) | 655 (36) | 1.04 (0.95–1.15) | 1.12 (0.99–1.26) |
 Other | 1375 (41) | 1.24 (1.14–1.34) | 1.16 (1.06–1.27) | 1223 (37) | 1.10 (1.01–1.19) | 1.14 (1.04–1.25) |