Hellström Ann, Engström Eva, Hård Anna-Lena, Albertsson-Wikland Kerstin, Carlsson Björn, Niklasson Aimon, Löfqvist Chatarina, Svensson Elisabeth, Holm Sture, Ewald Uwe, Holmström Gerd, Smith Lois E H
Göteborg Pediatric Growth Research Center, Department of Pediatrics, Institute of the Health of Women and Children, Sweden.
Pediatrics. 2003 Nov;112(5):1016-20. doi: 10.1542/peds.112.5.1016.
Insulin-like growth factor I (IGF-I) is necessary for normal development of retinal blood vessels in mice and humans. Because retinopathy of prematurity (ROP) is initiated by abnormal postnatal retinal development, we hypothesized that prolonged low IGF-I in premature infants might be a risk factor for ROP.
We conducted a prospective, longitudinal study measuring serum IGF-I concentrations weekly in 84 premature infants from birth (postmenstrual ages: 24-32 weeks) until discharge from the hospital. Infants were evaluated for ROP and other morbidity of prematurity: bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), and necrotizing enterocolitis (NEC).
Low serum IGF-I values correlated with later development of ROP. The mean IGF-I +/- SEM level during postmenstrual ages 30-33 weeks was lowest with severe ROP (25 +/- 2.41 micro g/L), 29 +/- 1.76 micro g/L with moderate ROP, and 33 +/- 1.72 micro g/L with no ROP. The duration of low IGF-I also correlated strongly with the severity of ROP. The interval from birth until serum IGF-I levels reached >33 micro g/L was 23 +/- 2.6 days for no ROP, 44 +/- 4.8 days for moderate ROP, and 52 +/- 7.5 days for severe ROP. Each adjusted stepwise increase of 5 micro g/L in mean IGF-I during postmenstrual ages 30 to 33 weeks decreased the risk of proliferative ROP by 45%. Other complications (NEC, BPD, IVH) were correlated with ROP and with low IGF-I levels. The relative risk for any morbidity (ROP, BPD, IVH, or NEC) was increased 2.2-fold (95% confidence interval: 1.41-3.43) if IGF-I was <or=33 micro g/L at 33 weeks' postmenstrual age.
These results indicate that persistent low serum concentrations of IGF-I after premature birth are associated with later development of ROP and other complications of prematurity. IGF-I is at least as strong a determinant of risk for ROP as postmenstrual age at birth and birth weight.
胰岛素样生长因子I（IGF-I）对小鼠和人类视网膜血管的正常发育至关重要。由于早产儿视网膜病变（ROP）是由出生后视网膜异常发育引发的，我们推测早产儿长期低IGF-I水平可能是ROP的一个危险因素。
我们进行了一项前瞻性纵向研究，从出生（孕龄：24 - 32周）起每周测量84例早产儿的血清IGF-I浓度，直至出院。对婴儿进行ROP及其他早产相关疾病评估：支气管肺发育不良（BPD）、脑室内出血（IVH）和坏死性小肠结肠炎（NEC）。
血清IGF-I水平低与ROP的后期发生相关。孕龄30 - 33周期间，重度ROP患儿的平均IGF-I±SEM水平最低（25±2.41μg/L），中度ROP患儿为29±1.76μg/L，无ROP患儿为33±1.72μg/L。IGF-I水平低的持续时间也与ROP的严重程度密切相关。从出生到血清IGF-I水平达到>33μg/L的间隔时间，无ROP患儿为23±2.6天，中度ROP患儿为44±4.8天，重度ROP患儿为52±7.5天。孕龄30至33周期间，平均IGF-I每调整性逐步升高5μg/L，增殖性ROP的风险降低45%。其他并发症（NEC、BPD、IVH）与ROP及低IGF-I水平相关。如果孕龄33周时IGF-I≤33μg/L，任何疾病（ROP、BPD、IVH或NEC）的相对风险增加2.2倍（95%置信区间：1.41 - 3.43）。
这些结果表明，早产出生后持续低血清IGF-I浓度与ROP及其他早产并发症的后期发生有关。IGF-I至少与出生时的孕龄和出生体重一样，是ROP风险的重要决定因素。
