Table 1.
Baseline characteristics of studies included in the meta-analysis
| Study (year) | N | Male (%) | Mean Age |
Therapy | Regimen | Therapy Duration |
End-point | Median FU (years) |
Relapse definition |
Relapse | Person-years | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High Dose 4-aminoquinolines | ||||||||||||
| No phlebotomy | Malkinson (1980)(11) | 6 | 42(66.7) | 50.9 | HCQ | varying dose that increased up to 400 mg daily | 5–13 months | UP 15–281 (ULN<26) mcg/d | 2.4 | Biochemical and/or Clinical | 4 (67%) | 14.4 |
| Tsega (1987)(25) | 46 | 44(95.7) | 46 | Chloroquine | 500 mg/d | 10 days | - | 2.7 | Biochemical and Clinical | 6 (13%) | 124.2 | |
| Phlebotomy | Wennersten (1982)(24) | 21 | 14(66.7) | 55.3 | Chloroquine | 250 mg/d* | 7 days | Drug course | 2.5 | Clinical or Biochemical | 9 (43%) | 52.5 |
| Petersen (1992)(26) | 65 | 42 (64.6) | 43 | HCQ | 250 mg three times daily** | 3 days | Drug course | 2.8 | Clinical and/or Biochemical | 23 (35%) | 182 | |
| Rossmann-Ringdahl (2007)(27) | 57 | 36(63.2) | 59.7 | Chloroquine | 250 mg/d*** | 7 days | Drug course | 11 | Biochemical | 27 (47%) | 627 | |
| Total | 195 | 69 (35%) | 1000.1 | |||||||||
| Low Dose 4-aminoquinolines | ||||||||||||
| Kordac (1977)(28) | 112 | - | - | Chloroquine | 125 mg biw | 8–18 months | UP<100 mcg/d | 4 | - | 38 (34%) | 448 | |
| Ashton (1984)(29) | 7 | 7(100) | 57 | Chloroquine | 125 mg biw | 14.9 months | UP<~100 nmol/d | 2.4 | Biochemical | 4 (57%) | 16.8 | |
| Valls (1994)(30) | 53 | 51 (96.2) | 47.4 | Chloroquine | 125 mg biw x 2wks. then 250 mg biw | 1–12 months (median 8 months) | UP<100 mcg/L | 3 | - | 22 (49%) | 159 | |
| Wollina (2009)(31) | 55 | 41 (65.1) | - | Chloroquine | 125 or 250 mg biw | 12 months | Normal UP | 1 | Biochemical and Clinical | 16 (29%) | 63 | |
| Singal(2015)(32) | 15 | - | - | HCQ | 100 mg twice weekly | - | Plasma porphyrin concentration < 0.9 mcg/dl with cessation of skin lesions | 1 | Biochemical | 8 (53%) | 15 | |
| Total | 242 | 88 (36.3%) | 701.8 | |||||||||
| Phlebotomy | ||||||||||||
| Epstein (1968)(33) | 20 | 14 (70) | Phlebotomy | 0.5 L every ~2 weeks | 2.5–8.5 months | Reduced hemoglobin, serum iron or iron saturation | 3 | Biochemical | 2 (10%) | 60 | ||
| Lundvall (1982)(34) | 44 | - | Phlebotomy | 0.4–0.5 L weekly | 1–7 months | Hemoglobin constantly 10–11 mg/dL | 6 | Biochemical | 9 (20%) | 264 | ||
| Singal (2015)(32) | 24 | - | Phlebotomy | - | - | Plasma porphyrin concentration < 0.9 mcg/dl with cessation of skin lesions | 1 | Biochemical | 7(29%) | 24 | ||
| Total | 88 | 18 (20.5%) | 348 | |||||||||
*
1–2 phlebotomies 300 mL each at 3–7-day interval,
**
Phlebotomy 500 mL 1–3 weeks before in 32 patients with very high UP or cirrhosis,
***
2–3 phlebotomies of average 750 mL of blood,
-; missing data in the original studies, biw; bi-weekly, CI; confidence internal, HCQ; hydroxychloroquine, N; total number of cases, MINORS; Methodological index for non-randomized studies, ULN; upper limit of normal, UP; uroporphyrin, wk.; week,