TABLE 4.

Summary of Studies Reporting IGF-1 Index As a Predictor of Treatment Failure

Study	N	Median IGF-1 index (range)	IGF-1i threshold assessed	HR (95% CI), P value
Pollock et al, 200737	46	2.25 (1.05-7.0)	2.25	2.9 (1.2-6.9), .02
Losa et al, 200841	83	1.83 (1.35-2.56)b	1.83	2.6 (1.3-5.1), .01
Liu et al, 201242	40	1.9 (0.8-4.6)	1.5	9.7 (2.3-40), .002
Kong et al, 201940	138	NR	2.0	2.3 (1.2-4.5), .01
Present study (IGF-1i ≥ 2.25)a	102	1.66 (1.37-3.22)b	2.25	2.0 (1.1-3.8), .02

HR, hazard ratio; IGF-1_i, insulin-like growth factor-1 index; IQR, interquartile range; NR, not reported.

^aCohort partially overlaps with Pollock et al³⁷; data reported Table 4 transformed to HR for treatment failure, to facilitate interpretation.

^bIQR reported.