TABLE 3.

Clinical determinants associated with QTc prolongation

Factor	Clinical determinants associated with:
	ΔQTcSSB interval prolongation						Absolute QTcSSB interval prolongation
	≤30 msa	31–60 ms	>60 ms	P value for:			≤450 msa	451–480 ms	481–500 ms	>500 ms	P value for:
				≤30 ms vs 31–60 ms	≤30 ms vs >60 ms	All groups					≤450 ms vs 451–480 ms	≤450 ms vs 481–500 ms	450 ms vs >500 ms	All groups
No. (%) of patients	638 (64.2)	286 (28.8)	70 (7.0)				481 (48.4)	408 (41.0)	78 (7.8)	27 (2.7)
No. (%) female	322 (50.5)	161 (56.3)	33 (47.1)	0.117	0.617	0.186	229 (47.6)	234 (57.4)	39 (50.0)	14 (50.0)	0.004b	0.715	0.696	0.036b
No. (%) with hypokalemia (<3.5 mmol/liter)	87 (13.6)	52 (18.2)	7 (10.0)	0.090	0.463	0.101	65 (13.5)	63 (15.4)	11 (14.1)	6 (22.2)	0.444	0.860	0.247	0.580
Body temp (°C) [median (IQR)]	37.1 (36.6–37.8)	37.5 (36.8–38.4)	37.6 (36.8–38.6)	<0.0001b	0.006b	<0.0001b	37.2 (36.6–38.0)	37.3 (36.7–38.0)	37.4 (36.8–37.9)	37.0 (36.5–37.3)	>0.999	>0.999	0.543	0.437
Age (yr) [median (IQR)]	7 (5–14)	8 (5–12)	8 (5–10)	>0.999	>0.999	0.873	8 (5–15)	7 (4–13)	8 (5–11)	9 (6–12)	0.675	>0.999	>0.999	0.489
Potassium (mmol/liter) [median (IQR)]	4.05 (3.70–4.47)	4.01 (3.70–4.40)	4.16 (3.80–4.49)	0.332	0.383	0.111	4.10 (3.70–4.50)	4.00 (3.70–4.40)	4.01 (3.60–4.38)	3.88 (3.60–4.30)	0.351	0.837	0.164	0.126
Baseline QTcSSB interval (ms) [median (IQR)]	425 (413–435)	422 (406–434)	415 (391–433)	0.015b	0.002b	0.0004b	416 (403–427)	428 (419–439)	436 (424–450)	435 (425–450)	<0.0001b	<0.0001b	<0.0001b	<0.0001b
Piperaquine Cmax (ng/ml) [median (IQR)]	694 (442–1,030)	814 (546–1,110)	830 (550–1,120)	0.0004b	0.083	0.0003b	651 (421–960)	783 (517–1,100)	962 (656–1,320)	905 (664–1,150)	<0.0001b	<0.0001b	0.045b	<0.0001b

^aReference groups.

^bStatistically significant.