|Year : 2015 | Volume
| Issue : 7 | Page : 914-918
Incidence and Risk Factors of Retinopathy of Prematurity in Two Neonatal Intensive Care Units in North and South China
Yi Chen1, Deng Xun1, Ya-Cong Wang2, Bin Wang3, Shao-Hui Geng2, Hui Chen3, Yan-Tao Li2, Xiao-Xin Li1
1 Department of Ophthalmology, People's Hospital, Peking University, Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing 100044, China
2 Department of Ophthalmology, The Fourth Hospital of Shijiazhuang, Shijiazhuang, Hebei 050011, China
3 Department of Pediatric, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong 510282, China
|Date of Submission||05-Jan-2015|
|Date of Web Publication||31-Mar-2015|
Prof. Xiao-Xin Li
Department of Ophthalmology, People's Hospital, Peking University, 11 Xizhimen South Street, Xicheng District, Beijing 100044
Source of Support: None, Conflict of Interest: None
Background: To investigate the incidence and risk factors of retinopathy of prematurity (ROP) in two Neonatal Intensive Care Units in North and South of China, respectively.
Methods: We studied data concerning 472 infants with gestational age (GA) ≤34 weeks or birth weight (BW) ≤2000 g who were admitted to the Zhujiang Hospital of Southern Medical University and the Fourth Hospital of Shijiazhuang between January 1, 2011 and December 31, 2011. Clinical information about perinatal neonates was collected and was confirmed by reviewing medical charts. The incidence and severity of ROP were assessed in the screened population. Main outcome measures are the incidence and severity of ROP. The relationship of clinical risk factors and the development of ROP were analyzed.
Results: The overall incidence of ROP was 12.7%, and the overall incidence of type 1 ROP was 2.3%; 9.4% of infants in Zhujiang Hospital had ROP compared to 15.0% infants in the Fourth Hospital of Shijiazhuang developed ROP, and the difference is statistically significant. ROP was significantly associated with GA (odds ratio [OR]: 0.77 [0.62-0.95], P = 0.015), BW (OR: 0.998 [0.996-0.999], P = 0.008), maternal supplemental oxygen administration before and during delivery (OR: 4.27 [1.21-15.10], P = 0.024) and preeclampsia (OR: 6.07 [1.73-21.36] P = 0.005). The risk factors for ROP are different in two hospitals. In Zhujiang Hospital, BW is the independent risk factors for ROP while GA, BW and preeclampsia in the Fourth Hospital in Shijiazhuang
Conclusions: Retinopathy of prematurity incidence is different based on area. Incidence of ROP is still high in China. More efforts need to prevent ROP.
Keywords: Birth Weight; Gestational Age; Incidence; Retinopathy of Prematurity
|How to cite this article:|
Chen Y, Xun D, Wang YC, Wang B, Geng SH, Chen H, Li YT, Li XX. Incidence and Risk Factors of Retinopathy of Prematurity in Two Neonatal Intensive Care Units in North and South China. Chin Med J 2015;128:914-8
|How to cite this URL:|
Chen Y, Xun D, Wang YC, Wang B, Geng SH, Chen H, Li YT, Li XX. Incidence and Risk Factors of Retinopathy of Prematurity in Two Neonatal Intensive Care Units in North and South China. Chin Med J [serial online] 2015 [cited 2018 Dec 14];128:914-8. Available from: http://www.cmj.org/text.asp?2015/128/7/914/154294
| Introduction|| |
Retinopathy of prematurity (ROP) is a vasoproliferative eye disease, first described in 1942.  It is a major cause of preventable blindness of children in the developing and developed world.  The survival of premature infants has increased with the improvement of neonatal care.  Consequently, this may have been accompanied by an increase in the incidence of ROP. , However, the incidence estimates from population-based studies vary among countries with similar Neonatal Intensive Care Unit (NICU).  In a prospective study of Sweden,  ROP was detected in 73% infants with a gestational age (GA) <27 weeks at birth. In a study in Norway  in infants with a GA of <28 weeks at birth, ROP was reported in 33% infants. Different incidences were also reported in Belgium,  Australia and New Zealand,  Austria  and Finland.  ROP is under constant epidemiological study around the world.
Improved neonatal care in China has increased the survival of very low birth weight (VLBW) premature infants and has consequently increased the incidence of ROP.  Study from Beijing, China  of infants with birth weight (BW) <2000 g or GA <34 weeks at birth ROP was reported in 10.8% infants. Nevertheless, there are limited studies on the incidence and risk factors of this important morbidity among preterm infants in a different area of China. Although significant advances have been made in perinatal care, ROP remains a serious complication in prematurely born individuals.
Low GA, ,,,, low BW ,,,, and prolonged exposure to supplementary oxygen  have been shown consistent and significant association with ROP. Other risk factor includes plasma insulin-like growth factor-1,  postnatal weight gain, , hyperglycemia,  insulin use,  nutrition,  neonatal infection, ,, blood transfusion, , genetic factors,  mechanical ventilation,  sepsis,  intraventricular hemorrhage,  surfactant therapy  and anemia  and apnea.  The precise of these factors in the progression of ROP has not been determined. In China, several studies elucidated that the incidence of ROP is lower in the developed regions such as Shanghai and Guangdong in the South of China than in the less developed regions in the North of China  despite the reason is unclear.
The aim of this prospective study was to evaluate the incidence of ROP in preterm infants at the Zhujiang Hospital in the South of China and the Fourth Hospital in Shijiazhuang in the North of China, to identify the prenatal, postnatal and regional risk factors for its development.
| Methods|| |
The prospective study was carried out at the Zhujiang Hospital of Southern Medical University in South of China and the Fourth Hospital of Shijiazhuang in North of China between January 1, 2011 and December 31, 2011. The Neonatal Department of Zhujiang Hospital in Guangzhou and the Fourth Hospital of Shijiazhuang in Shijiazhuang are both high-risk perinatal centers. About 500 preterm infants are admitted to the NICUs in Zhujiang Hospital every year, about 200 of them need to be screened for ROP. While about 300 preterm infants need to be screened in the Fourth Hospital of Shijiazhuang every year. All preterm infants admitted to the NICU between January 1, 2011 and December 31, 2011, who received eye examination for ROP, were eligible for the study. Ethical Committee clearance from the institution was obtained.
Eye examination schedules
The screening examinations were performed on all infants who met the criteria bellowed:
- All preterms with GA ≤34 weeks and/or BW ≤2000 g
- Selected preterm infants who had prolonged exposure to oxygen who were at risk for ROP.
Infants were examined according to the 2004 Chinese Ministry of Health guidelines on oxygenation policies and prevention and treatment of ROP.  The first examination was at 4 weeks after birth.
Eye examination methods
Ophthalmologists who had sufficient knowledge and experience to identify the location and sequential retinal changes of ROP performed all examinations. Pupils were dilated with 0.5% tropicamide and 0.5% phenyleprine drops 2 h before examination. Indirect ophthalmoscopy was routinely performed used a lid speculum and scleral indentation after topical anesthesia. Digital retinal images were also obtained using Retcam for objective documentation of retinal findings.
Monitoring and management
Examination was performed on a weekly or biweekly basis, depending on the retinal findings and continued until vascularization had reached zone 3, or the disease progressed to type 1 ROP defined as early treatment for ROP (ET-ROP) or established ROP was definitely regressing. The retinal findings were classified according to the International Classification of ROP including the stage, extent, zone, and presence or absence of plus disease.  Indication for treatment is the type 1 ROP according to ET-ROP study.
Genders of newborn and delivery pattern were recorded. The perinatal variables documented included preeclampsia (defined as systolic blood pressure >140 mmHg or diastolic blood pressure >90 mmHg with proteinuria) and presence of fetal distress, maternal supplemental oxygen administration before and during delivery. The following risk factors occurring during the first 4 weeks after birth were recorded: GA, BW, respiratory distress syndrome, surfactant administration, intraventricular hemorrhage, hyperbilirubinemia, blood transfusion, sepsis, duration of oxygen and duration of continuous positive airway pressure.
Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS version 16, SPSS Inc, Chicago, IL, USA) program. GA and BW in different groups were compared using t-test. Chi-square tests were used to compare the rate of ROP in different groups. Univarate analysis was used to explore variables associated with ROP with the appropriate significance of P < 0.05, and those found to be significant were included in a logistic regression model using a backward stepwise method. In the model, comparison was made between the groups without ROP and with ROP. The odds ratio (OR) and 95% confidence interval (CI) for each possible risk factor were also calculated.
| Results|| |
During the study period, 472 infants who met the inclusion criterion were admitted to the two hospitals. Totally, 202 infants were admitted to the Zhujiang Hospital of Southern Medical University and the rest to the Fourth Hospital in Shijiazhuang. Totally, 4 of the 472 babies were lost to follow-up.
Data were available on 468 babies, and 61.5% of whom were male. Only 6 had a GA of <28 weeks and 3 weighed <1000 g. GA ranged from 26.0 to 36.9 (mean 32.3 [2.0]) weeks and BW from 850 to 2450 (mean 1646.6 [292.4.8] g). Any stage of ROP was detected in 58/468 babies (12.4%) and distribution of ROP by GA and BW is shown in [Table 1]a and [Table 1]b. The rate of type 1 ROP was high in very premature babies that is <30 weeks (6/43, 14.0%) [Table 1]a. Only 0.9% of infants with gestational weeks ≥30 weeks developed type 1 ROP (P < 0.001). Low BW infants were more at risk than bigger babies, as 16.4% (21/128) with BW <1500 g developed any stage ROP compared with 10.9% (37/340) among babies with BW ≥1500 g [Table 1]b.
The GA showed no significant difference between the two hospitals (P = 0.839), while babies admitted to Zhujiang Hospital had bigger BW (P = 0.029) and more male gender babies were admitted to the Zhujiang Hospital (P = 0.015) [Table 2]. The incidence of ROP is higher in Shijiazhuang Fourth Hospital than that in the Zhujiang Hospital with significant statistical difference (P = 0.048) and the incidence of type 1 ROP is higher in Shijiazhuang Fourth Hospital without significant difference (P = 0.199) [Table 2].
|Table 2: Comparison of characteristics and incidence of ROP between two hospitals|
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The mean GA of infants with ROP was significantly lower than those without ROP (mean 31.2 [2.0] weeks vs. 32.5 [1.9] weeks, P < 0.001). Furthermore, the means GA of type 1 ROP were also significantly lower than those without ROP and mild ROP (mean 29.6 [2.4] weeks vs. 32.4 [1.9] weeks, P < 0.001). The mean BW of infants without ROP was 1674.0.1 ± 294.5 g, while it was 1440.0 ± 172.1 g with ROP (P < 0.001). When it comes to infants with no ROP plus mild ROP and type 1 ROP, the mean BW was 1649.6 ± 293.1 and 1426.0 ± 147.3 g (P = 0.020), respectively.
Results of univariate analysis of maternal and postnatal factors for ROP are shown in [Table 3]. In the multivariate logistic regression analysis, four variables were identified as significant, independent risk factors for ROP [Table 4]: GA, BW, preeclampsia and maternal oxygen administration.The risk factors for ROP are different in two hospitals. In Zhujiang Hospital, BW is the independent risk factors for ROP, while GA, BW and preeclampsia in the Fourth Hospital in Shijiazhuang [Table 5].
|Table 3: Univariate analysis of maternal and postnatal risk factor for retinopathy of prematurity|
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|Table 5: Independent maternal and postnatal risk factors for the retinopathy of prematurity in Zhujiang Hospital and the Fourth Hospital in Shijiazhuang|
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| Discussion|| |
Our study indicates that the incidence of any ROP and type 1 ROP was 12.7% and 2.3% respectively. It is corresponded to the incidence reported in six NICUs in Beijing, China  but very different from the studied in developed countries. , This variation might be partly accounted for by differences in the proportions of infants at high risk of ROP who survive when born at an early GA. In addition, the screening criteria for inclusion were BW ≤2000 g or GA ≤34 weeks, being much wider than those used in other studies. For example, the cry therapy of retinopathy of prematurity (CRTO-ROP)  included infants with weights of <1250 g and showed an incidence of 65.8%. We used the criteria recommended by the Chinese Medical Association, which was based on a review of criteria used in other countries , and on clinical experience of China.  Our study showed the mean BW of babies developing ROP to be 1440.0 (172.1) g and the mean GA was 31.2 (2.0) weeks suggesting that current screening criteria are suitable for these two hospitals.
In 1993, a study in the first Affiliated Hospital of Peking University reported the incidence of any stage of ROP was 20.3%.  In 2005, six NICUs in Beijing screened 639 babies (using the same criteria as the current study) and 10.8% of babies developed ROP and 3.6% developed threshold ROP  compared with 12.7% and 2.3% respectively in current study (P = 0.33, P = 0.21). It is disappointed that the data suggested that the incidence had no changed substantially over time since efforts had been done. Perhaps increased survival of very immature infants at high risk for the disease balanced against improved neonatal intensive care for ROP can account for this finding. Although no individual study has been conclusive as to the best SpO 2 target, strict management of oxygen to minimize alternating hypoxia and hyperoxia and avoidance of undesired high oxygen saturations seem to be the most promising strategies to prevent ROP. 
In this study, GA and BW were independently associated with ROP that were consistent with many other studies. ,, We also found preeclampsia, and maternal oxygen administration to be significant risk factors of any stage of ROP. Few studies have been published to determine the association of preeclampsia with ROP and the results reported are conflicting. ,,, Fortes Filho et al.  reported that preesclapmsia reduced the risk for any stage of ROP by 60% in early preterm infants (<32 weeks). Holmström et al., in a population-based study, reported that preeclampsia was less common in the non-ROP group, but the difference was not statistically significant.  Another retrospective study of 252 VLBW infants in Taiwan  found that maternal preeclampsia (OR: 2.52, 95% CI: [1.32, 4.7]) predicted the development of threshold ROP. More studies and a meta-analysis are needed to investigate the impact of preeclampsia on ROP.
In addition, our study found that the incidence of ROP is lower in Zhujiang Hospital in South of China than in The Fourth Hospital in Shijiazhuang in the north with P = 0.048. This is consistent with other results published in Chinese journals.  The discrepancy is probably associated with the child healthcare in different regions including prenatal care, delivery care, and postnatal care as well as general socioeconomic conditions, such as household income, educational levels and government initiatives.  It was also established in our study that different regions have different risk factors of ROP. This could also be an explanation of the prevalence variation of ROP. The incidence of threshold ROP is lower in Zhujiang Hospital but without significantly difference. Difference risk factors of threshold ROP in two hospitals may be responsible. Some of the differences could due to observer differences, changes in the indications for treatment and variation in exposure to risk factors. At the same time, the mean BW of infants in Zhujiang Hospital was higher than those in the Fourth Hospital in Shijiazhuang. It also may contribute to the difference of the incidence of ROP between two hospitals.
The follow-up of infants with threshold ROP is essential to minimize blindness and long-term visual morbidity in these infants. More efforts need to be done not only to reduce the incidence of ROP but also improve the guideline to ensure that all babies at risk receive a timely screening examination.
| References|| |
Terry TL. Extreme prematurity and fibroblastic overgrowth of persistent vascular sheath behind each crystalline lens. Am J Opthalmol 1942;25:203-6.
Coats DK, Miller AM, Hussein MA, McCreery KM, Holz E, Paysse EA. Involution of retinopathy of prematurity after laser treatment: Factors associated with development of retinal detachment. Am J Ophthalmol 2005;140:214-22.
Domanico R, Davis DK, Coleman F, Davis BO. Documenting the NICU design dilemma: Comparative patient progress in open-ward and single family room units. J Perinatol 2011;31:281-8.
Valentine PH, Jackson JC, Kalina RE, Woodrum DE. Increased survival of low birth weight infants: Impact on the incidence of retinopathy of prematurity. Pediatrics 1989;84:442-5.
Gibson DL, Sheps SB, Uh SH, Schechter MT, McCormick AQ. Retinopathy of prematurity-induced blindness: Birth weight-specific survival and the new epidemic. Pediatrics 1990;86:405-12.
Hellström A, Smith LE, Dammann O. Retinopathy of prematurity. Lancet 2013;382:1445-57.
Austeng D, Källen KB, Ewald UW, Jakobsson PG, Holmström GE. Incidence of retinopathy of prematurity in infants born before 27 weeks' gestation in Sweden. Arch Ophthalmol 2009;127:1315-9.
Markestad T, Kaaresen PI, Rønnestad A, Reigstad H, Lossius K, Medbø S, et al.
Early death, morbidity, and need of treatment among extremely premature infants. Pediatrics 2005;115:1289-98.
Allegaert K, de Coen K, Devlieger H, EpiBel Study Group. Threshold retinopathy at threshold of viability: The EpiBel study. Br J Ophthalmol 2004;88:239-42.
Darlow BA, Hutchinson JL, Henderson-Smart DJ, Donoghue DA, Simpson JM, Evans NJ, et al.
Prenatal risk factors for severe retinopathy of prematurity among very preterm infants of the Australian and New Zealand Neonatal Network. Pediatrics 2005;115:990-6.
Weber C, Weninger M, Klebermass K, Reiter G, Wiesinger-Eidenberger G, Brandauer M, et al.
Mortality and morbidity in extremely preterm infants (22 to 26 weeks of gestation): Austria 1999-2001. Wien Klin Wochenschr 2005;117:740-6.
Tommiska V, Heinonen K, Lehtonen L, Renlund M, Saarela T, Tammela O, et al.
No improvement in outcome of nationwide extremely low birth weight infant populations between 1996-1997 and 1999-2000. Pediatrics 2007;119:29-36.
Quinn GE, Gilbert C, Darlow BA, Zin A. Retinopathy of prematurity: An epidemic in the making. Chin Med J (Engl) 2010;123:2929-37.
Chen Y, Li XX, Yin H, Gilbert C, Liang JH, Jiang YR, et al.
Risk factors for retinopathy of prematurity in six neonatal intensive care units in Beijing, China. Br J Ophthalmol 2008;92:326-30.
Bardin C, Zelkowitz P, Papageorgiou A. Outcome of small-for-gestational age and appropriate-for-gestational age infants born before 27 weeks of gestation. Pediatrics 1997;100:E4.
Regev RH, Lusky A, Dolfin T, Litmanovitz I, Arnon S, Reichman B, et al.
Excess mortality and morbidity among small-for-gestational-age premature infants: A population-based study. J Pediatr 2003;143:186-91.
Allegaert K, Vanhole C, Casteels I, Naulaers G, Debeer A, Cossey V, et al.
Perinatal growth characteristics and associated risk of developing threshold retinopathy of prematurity. J AAPOS 2003;7:34-7.
Dhaliwal CA, Fleck BW, Wright E, Graham C, McIntosh N. Retinopathy of prematurity in small-for-gestational age infants compared with those of appropriate size for gestational age. Arch Dis Child Fetal Neonatal Ed 2009;94:F193-5.
Kim TI, Sohn J, Pi SY, Yoon YH. Postnatal risk factors of retinopathy of prematurity. Paediatr Perinat Epidemiol 2004;18:130-4.
Hellström A, Engström E, Hård AL, Albertsson-Wikland K, Carlsson B, Niklasson A, et al.
Postnatal serum insulin-like growth factor I deficiency is associated with retinopathy of prematurity and other complications of premature birth. Pediatrics 2003;112:1016-20.
Gyllensten LJ, Hellstrom BE. Experimental approach to the pathogenesis of retrolental fibroplasia. III. Changes in the eye induced by exposure of newborn mice to general hypoxia. Br J Ophthalmol 1955;39:409-15.
Kaempf JW, Kaempf AJ, Wu Y, Stawarz M, Niemeyer J, Grunkemeier G. Hyperglycemia, insulin and slower growth velocity may increase the risk of retinopathy of prematurity. J Perinatol 2011;31:251-7.
Hansen-Pupp I, Löfqvist C, Polberger S, Niklasson A, Fellman V, Hellström A, et al.
Influence of insulin-like growth factor I and nutrition during phases of postnatal growth in very preterm infants. Pediatr Res 2011;69:448-53.
Mittal M, Dhanireddy R, Higgins RD. Candida sepsis and association with retinopathy of prematurity. Pediatrics 1998;101:654-7.
Manzoni P, Maestri A, Leonessa M, Mostert M, Farina D, Gomirato G. Fungal and bacterial sepsis and threshold ROP in preterm very low birth weight neonates. J Perinatol 2006;26:23-30.
Tolsma KW, Allred EN, Chen ML, Duker J, Leviton A, Dammann O. Neonatal bacteremia and retinopathy of prematurity: The ELGAN study. Arch Ophthalmol 2011;129:1555-63.
Cooke RW, Clark D, Hickey-Dwyer M, Weindling AM. The apparent role of blood transfusions in the development of retinopathy of prematurity. Eur J Pediatr 1993;152:833-6.
Giannantonio C, Papacci P, Cota F, Vento G, Tesfagabir MG, Purcaro V, et al.
Analysis of risk factors for progression to treatment-requiring ROP in a single neonatal intensive care unit: Is the exposure time relevant? J Matern Fetal Neonatal Med 2012;25:471-7.
Husain SM, Sinha AK, Bunce C, Arora P, Lopez W, Mun KS, Reddy MA, Adams GG. Relationships between maternal ethnicity, gestational age, birth weight, weight gain, and severe retinopathy of prematurity. J Pediatr 2013;163:67-72.
Shah VA, Yeo CL, Ling YL, Ho LY. Incidence, risk factors of retinopathy of prematurity among very low birth weight infants in Singapore. Ann Acad Med Singapore 2005;34:169-78.
Gupta VP, Dhaliwal U, Sharma R, Gupta P, Rohatgi J. Retinopathy of prematurity - risk factors. Indian J Pediatr 2004;71:887-92.
Xu Y, Zhou X, Zhang Q, Ji X, Zhang Q, Zhu J, et al.
Screening for retinopathy of prematurity in China: A neonatal units-based prospective study. Invest Ophthalmol Vis Sci 2013;54:8229-36.
Chinese Medical Association. Guidelines on oxygenation policies and on prevention and treatment of retinopathy of prematurity. Zhonghua Yan Ke Za Zhi 2005;41:375-6.
International Committee for the Classification of Retinopathy of Prematurity. The International Classification of Retinopathy of Prematurity revisited. Arch Ophthalmol 2005;123:991-9.
Gilbert C, Fielder A, Gordillo L, Quinn G, Semiglia R, Visintin P, et al.
Characteristics of infants with severe retinopathy of prematurity in countries with low, moderate, and high levels of development: Implications for screening programs. Pediatrics 2005;115:e518-25.
Palmer EA, Flynn JT, Hardy RJ, Phelps DL, Phillips CL, Schaffer DB, et al.
Incidence and early course of retinopathy of prematurity. The Cryotherapy for Retinopathy of Prematurity Cooperative Group. Ophthalmology 1991;98:1628-40.
Jiang YR, Li XX, Qi HJ. A study on risk factors of retinopathy of prematurity. Zhonghua Yan Ke Za Zhi 1994;30:427-30.
Kopylov U, Sirota L, Linder N. Retinopathy of prematurity - Risk factors. Harefuah 2002;141:1066-9, 89.
Zayed MA, Uppal A, Hartnett ME. New-onset maternal gestational hypertension and risk of retinopathy of prematurity. Invest Ophthalmol Vis Sci 2010;51:4983-8.
Fortes Filho JB, Costa MC, Eckert GU, Santos PG, Silveira RC, Procianoy RS. Maternal preeclampsia protects preterm infants against severe retinopathy of prematurity. J Pediatr 2011;158:372-6.
Holmström G, Thomassen P, Broberger U. Maternal risk factors for retinopathy of prematurity - A population-based study. Acta Obstet Gynecol Scand 1996;75:628-35.
Yang CY, Lien R, Yang PH, Chu SM, Hsu JF, Fu RH, et al.
Analysis of incidence and risk factors of retinopathy of prematurity among very-low-birth-weight infants in North Taiwan. Pediatr Neonatol 2011;52:321-6.
Yanping W, Lei M, Li D, Chunhua H, Xiaohong L, Mingrong L, et al.
A study on rural-urban differences in neonatal mortality rate in China, 1996-2006. J Epidemiol Community Health 2010;64:935-6.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
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