Retinopathy of prematurity and maternal age

Trends in Retinopathy of Prematurity Among Preterm Infants in California, 2012 to 2021

Importance

The incidence of retinopathy of prematurity (ROP) has been increasing in the US since 2003. Understanding the progression of and racial disparities in ROP incidence in California can provide a contrasting perspective that may guide future research and practice in the management and prevention of ROP.

Objective

To describe how the screening and incidence of ROP among very preterm infants in California changed from January 1, 2012, to December 31, 2021.

Design, Setting, and Participants

This study used a cohort of very preterm infants (defined as infants born prior to 32 weeks' gestational age or weighing less than 1500 g) admitted to 60 neonatal intensive care units across California from January 1, 2012, to December 31, 2021. Among this cohort, several factors were examined, including (1) the clinical and sociodemographic covariates of the population with and without ROP, (2) trends in screening for ROP, and (3) the incidence of ROP in total and by race and ethnicity. Data analysis was performed in April 2024.

Exposures

Race and ethnicity and other birthing parental and infant descriptive characteristics.

Main Outcomes and Measures

Incidence rates of ROP and severe ROP. The primary measures were rates of ROP screening and incidence rates of ROP and severe ROP. Time trends in the risk of ROP and severe ROP were estimated using robust Poisson regression models.

Results

In this cohort of 39 269 very preterm infants (<32 weeks' gestational age) eligible for ROP screening, the mean (SD) infant gestational age was 28.6 (2.6) weeks. The mean (SD) birth weight was 1075 (274) g, and 48.6% of infants were female. The birthing parents of the population were 12.6% Asian, 13.3% Black, 44.9% Hispanic White or Hispanic other race, 0.7% Native American/Alaskan, 24.7% non-Hispanic White, and 1.0% Pacific Islander. From January 1, 2012, to December 31, 2021, in California, ROP screening rates remained steady at 95% or greater for eligible infants less than 30 weeks of gestational age for all race and ethnic subgroups. In this study cohort among all very preterm infants (<32 weeks' gestational age), the incidence of ROP decreased from 31% in 2012 to 29% in 2021. Incidence rates of ROP among Asian and Hispanic individuals decreased the most quickly compared to other racial and ethnic groups, narrowing disparities.

Conclusions and Relevance

In this cohort study, in contrast to increasing national trends, the total incidence of and racial and ethnic disparities in ROP incidence remained steady or decreased from 2012 to 2021 in California.

Risk Factors for Retinopathy of Prematurity in Preterm Infants in Kerman, Iran

Purpose

Retinopathy of prematurity (ROP) is the main cause of blindness in premature infants. Despite developments in neonatal care and management guidelines, ROP is becoming increasingly prevalent worldwide. Hence, the identification of risk factors for ROP is critical to diminish the burden of the disease.

Methods

This cross-sectional study included all infants with gestational age ≤ 36 weeks referred to the ophthalmology clinic at Shafa hospital, Kerman, Iran from 2014 to 2015. Ophthalmologic examinations were performed followed by demographic and ophthalmic data collection and analysis.

Results

A total of 579 preterm neonates were screened including 325 boys and 254 girls. The incidence of ROP was 17.96%. Mean birth weight (BW) and gestational age (GA) were 1668.0 grams and 31.2 weeks, respectively. The results indicated that BW, GA, duration of hospitalization and oxygen therapy were significantly related to the development of ROP, however, after multivariate logistic regression analysis, only BW and duration of hospitalization remained significant. There were no significant associations between gender, type of delivery, or assisted reproductive technologies, and ROP (P = 0.461, 0.461, and 0.826, respectively).

Conclusion

BW and duration of hospitalization were significant risk factors for ROP in the current study. BW was also strongly associated with the need for therapy.

Impact of advanced maternal age on neonatal morbidity: a systematic review

OBJECTIVE

This systematic review aimed to understand the impact of advanced maternal age (AMA) on the neonatal morbidity, based on the available scientific evidence.

METHODS

A systematic search was conducted on 22 November 2021, using the PubMed and Scopus databases to identify studies that compared the morbidity of neonates delivered to AMA mothers with that of neonates delivered to non-AMA mothers.

RESULTS

Sixteen studies that evaluated the effect of AMA on the neonatal morbidity were included in this review. Nine of these studies found some association between AMA and increased neonatal morbidity (with two of them only reporting an increase in asymptomatic hypoglycemia, and one only reporting an association in twins), six found no association between AMA and neonatal morbidity and one study found a decrease in morbidity in preterm neonates. The studies that found an increase in overall neonatal morbidity with AMA considered older ages for the definition of AMA, particularly ≥40 and ≥45 years.

CONCLUSION

The current evidence seems to support a lack of association between AMA and the neonatal morbidity of the delivered neonates. However, more studies focusing on the neonatal outcomes of AMA pregnancies are needed to better understand this topic.

Effects of TIMP-2 Polymorphisms on Retinopathy of Prematurity Risk, Severity, Recurrence, and Treatment Response

Tissue inhibitors of metalloproteinases (TIMPs) play a crucial role in endogenous angiogenesis besides the regulation of matrix metalloproteinase (MMP) activity. Associations between TIMP-2 gene polymorphisms and the risk of retinopathy of prematurity (ROP) were examined. Premature infants born between 2009 and 2018 were included. Five single-nucleotide polymorphisms (SNPs) of TIMP-2 were analyzed with real-time polymerase chain reaction (PCR). Multivariate logistic regression was applied to model associations between TIMP-2 polymorphisms and ROP susceptibility and severity. The GA+AA genotype in individuals with the TIMP-2 polymorphism of rs12600817 was associated with a higher risk of ROP (odds ratio [OR]: 1.518, 95% confidence interval [CI]: 1.028-2.242) compared with their wild-type genotypes. The AA genotype (OR: 1.962, 95% CI: 1.023-3.762) and the AA+GA genotype (OR: 1.686, 95% CI: 1.030-2.762) in individuals with the rs12600817 polymorphism had higher risks of severe, treatment-requiring ROP relative to their wild-type counterparts. In patients with treatment-requiring ROP, the AG+GG genotypes in the TIMP-2 polymorphism of rs2889529 were correlated with the treatment response (p = 0.035). The TIMP-2 polymorphism of rs12600817 help in predicting ROP risks in preterm infants, while the polymorphism of rs2889529 can serve as a genetic marker in evaluating the ROP treatment response.

The role of anti-vascular endothelial growth factor in treatment of retinopathy of prematurity-a current review

The review aims to evaluate the uses of conventional laser therapy and intravitreal injection of various anti-VEGF in terms of efficacy and side effects for the treatment of retinopathy of prematurity. A literature search of the publication, concerning conventional laser treatment and intravitreal injection of anti-VEGF for ROP. A total of 40 articles were reviewed after curation by the authors for relevance. Intravitreal anti-VEGF showed better ocular efficacy in zone I ROP while laser therapy had a lower recurrence rate in zone II. Comparing the two mainstay anti-VEGF agents, bevacizumab showed lower ROP recurrence rate than ranibizumab. Anti-VEGF has a higher chance in developing persistent peripheral avascularisation compared to conventional laser therapy, but a lower chance of developing high myopia. Ranibizumab has a lower systemic absorption than bevacizumab, despite having no difference in the incidence of persistent peripheral avascularisation. In conclusion, it is advised that intravitreal anti-VEGF should be used as the first-line treatment for zone I ROP while laser therapy should be the mainstay for zone II ROP owing to the different pathogenetic mechanisms. In patients with recurrence after initial anti-VEGF injection, that given ranibizumab may opt to repeat the injection while that given bevacizumab should consider supplement laser ablative treatment.

Development and Validation of a Deep Learning Model to Predict the Occurrence and Severity of Retinopathy of Prematurity

Importance

Retinopathy of prematurity (ROP) is the leading cause of childhood blindness worldwide. Prediction of ROP before onset holds great promise for reducing the risk of blindness.

Objective

To develop and validate a deep learning (DL) system to predict the occurrence and severity of ROP before 45 weeks' postmenstrual age.

Design, Setting, and Participants

This retrospective prognostic study included 7033 retinal photographs of 725 infants in the training set and 763 retinal photographs of 90 infants in the external validation set, along with 46 characteristics for each infant. All images of both eyes from the same infant taken at the first screening were labeled according to the final diagnosis made between the first screening and 45 weeks' postmenstrual age. The DL system was developed using retinal photographs from the first ROP screening and clinical characteristics before or at the first screening in infants born between June 3, 2017, and August 28, 2019.

Exposures

Two models were specifically designed for predictions of the occurrence (occurrence network [OC-Net]) and severity (severity network [SE-Net]) of ROP. Five-fold cross-validation was applied for internal validation.

Main Outcomes and Measures

Area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity to evaluate the performance in ROP prediction.

Results

This study included 815 infants (450 [55.2%] boys) with mean birth weight of 1.91 kg (95% CI, 1.87-1.95 kg) and mean gestational age of 33.1 weeks (95% CI, 32.9-33.3 weeks). In internal validation, mean AUC, accuracy, sensitivity, and specificity were 0.90 (95% CI, 0.88-0.92), 52.8% (95% CI, 49.2%-56.4%), 100% (95% CI, 97.4%-100%), and 37.8% (95% CI, 33.7%-42.1%), respectively, for OC-Net to predict ROP occurrence and 0.87 (95% CI, 0.82-0.91), 68.0% (95% CI, 61.2%-74.8%), 100% (95% CI, 93.2%-100%), and 46.6% (95% CI, 37.3%-56.0%), respectively, for SE-Net to predict severe ROP. In external validation, the AUC, accuracy, sensitivity, and specificity were 0.94, 33.3%, 100%, and 7.5%, respectively, for OC-Net, and 0.88, 56.0%, 100%, and 35.3%, respectively, for SE-Net.

Conclusions and Relevance

In this study, the DL system achieved promising accuracy in ROP prediction. This DL system is potentially useful in identifying infants with high risk of developing ROP.

Retinopathy prematurity: a systematic review and meta-analysis study based on neonatal and maternal risk factors

BACKGROUND

Retinopathy of prematurity is the abnormal development of retinal arteries in preterm neonates less than 32 weeks and weighing 1500 g, and less, which can lead to visual impairment during life and blindness. This study aims to investigate the relationship between some clinical characteristics of neonates and mothers with Retinopathy of prematurity in the world via a systematic review and meta-analysis.

MATERIALS AND METHODS

The present study is a systematic review and meta-analysis on the relationship between maternal and neonatal clinical variables with Retinopathy of prematurity in the world from the beginning of 2000 to the end of 2020. Accordingly, all English articles published on the topic were searched in scientific databases of Web of Science, PubMed, Google Scholar, Science Direct, and Scopus. The articles were searched independently by two researchers. Statistical analysis of data was performed using fixed and random effects model statistical tests in the meta-analysis, Cochran, meta-regression, I² index, Funnel plot, and Begg's by STATA software program, version 14.

RESULT

A total of 191 studies with a sample size of 140,921 persons were including in the meta-analysis. Accordingly, Preterm delivery ≤28 weeks (OR:6.3, 95% CI:4.9-8.1), Birth Weight ≤1000 g (OR:5.8, 95% CI:4.8-6.8), Birth Weight ≤1500 g (OR:4.8, 95% CI:3.8-6.1), PROM (OR:1.2, 95% CI:1.0-1.4), induced fertility (OR:1.9, 95% CI:1.1-3.0) and Chorioamnionitis (OR:1.5, 95% CI:1.0-2.2) There was a statistically significant association with retinopathy.

CONCLUSION

Based on the results of the present meta-analysis, the risk of retinopathy of prematurity in neonates born at 28 weeks and less, LBW (weight 1500 g and less), neonatal hypotension, chorioamnionitis, and induced fertility increases.

Maternal smoking as an independent risk factor for the development of severe retinopathy of prematurity in very preterm infants

BACKGROUND/OBJECTIVES

Retinopathy of prematurity (ROP) is a severe neonatal complication potentially leading to visual impairment and blindness. Known risk factors include preterm birth, low birth weight and respiratory support. Limited and contradictory data exist on the risk of maternal smoking during pregnancy on the development of ROP. This study aims to investigate smoking as an independent risk factor for the development of severe ROP (≥stage 3).

SUBJECTS/METHODS

This is a single centre retrospective case-control study of prospectively collected clinical data of infants born before 32 weeks of gestation between 2001 and 2012 at a tertiary care university hospital. The association between maternal smoking during pregnancy and the development of severe ROP was analyzed by multivariate logistic regression.

RESULTS

In total, n = 751 infants born < 32 weeks of gestation were included in this study. In total, 52.9% (n = 397) were diagnosed with ROP and 10.8% (n = 81) developed ROP ≥ stage 3. In total, 8.4% (n = 63) mothers presented with a history of smoking during pregnancy, which was associated to a higher rate of ROP (OR 2.59, 95% CI 1.10-6.12). Low gestational age, low birth weight and prolonged respiratory support were confirmed as independent risk factors for the development of severe ROP.

CONCLUSIONS

To date, this is the largest study evaluating the effect of maternal smoking on the development of ROP. Maternal smoking during pregnancy is identified as an independent risk factor for the development of severe ROP in preterm infants born < 32 weeks of gestation.

Retinopathy of prematurity: a review of risk factors and their clinical significance

Retinopathy of prematurity (ROP) is a retinal vasoproliferative disease that affects premature infants. Despite improvements in neonatal care and management guidelines, ROP remains a leading cause of childhood blindness worldwide. Current screening guidelines are primarily based on two risk factors: birth weight and gestational age; however, many investigators have suggested other risk factors, including maternal factors, prenatal and perinatal factors, demographics, medical interventions, comorbidities of prematurity, nutrition, and genetic factors. We review the existing literature addressing various possible ROP risk factors. Although there have been contradictory reports, and the risk may vary between different populations, understanding ROP risk factors is essential to develop predictive models, to gain insights into pathophysiology of retinal vascular diseases and diseases of prematurity, and to determine future directions in management of and research in ROP.

Incidence and Risk Factors of Retinopathy of Prematurity From 2 Neonatal Intensive Care Units in a Hong Kong Chinese Population

PURPOSE

To determine the incidence and risk factors of retinopathy of prematurity (ROP) in very low birth weight (VLBW) preterm Chinese infants.

DESIGN

Retrospective review.

METHODS

Medical records were reviewed for all neonates screened for ROP between January 2007 and December 2012 in Hong Kong. Screening was offered to VLBW (≤1500 g) and/or preterm (gestation, ≤32 weeks) neonates using the Royal College of Ophthalmologists ROP guideline and the International Classification of ROP by 3 pediatric ophthalmologists. Maternal and neonatal covariates were analyzed using univariate and multivariable logistic regression analyses for both ROP and type 1 ROP.

RESULTS

Of the 513 screened infants, the mean gestational age (GA) was 30.0 ± 2.5 weeks and the mean birth weight (BW) was 1232.6 ± 325.2 g. The incidence of ROP and type 1 ROP was 18.5% and 3.7%, respectively. In univariate analysis, a lighter BW, lower GA, blood transfusion, patent ductus arteriosus, nonsteroidal anti-inflammatory drug use, postnatal hypotension, inotropes usage, low Apgar scores, sepsis, mechanical ventilation, supplementary oxygen use, respiratory distress syndrome, anemia, surfactant use, and bronchopulmonary dysplasia were found to be associated with the development of both ROP and type 1 ROP (P < 0.05). In multivariable logistic regression analysis, BW, GA, and intraventricular hemorrhage were significant risk factors for ROP. Preeclampsia and eclampsia were the only protective factors for ROP development on multivariable logistic regression analysis (P = 0.02).

CONCLUSIONS

In VLBW preterm Chinese infants, lower GA, lighter BW, and intraventricular hemorrhage were significant risk factors for ROP, whereas preeclampsia and eclampsia were protective.

Role of Serum Levels of Vascular Endothelial Growth Factor and Its Receptor in Retinopathy of Prematurity

Background:

Retinopathy of prematurity (ROP) is a disorder of developing retina of low birth weight preterm infants which can lead to blindness. One theory attributes the fibrosis seen in ROP to deregulation of vascularization in the retina. Vascular endothelial growth factor (VEGF) is one of the important mediators involved in vascularization.

Objectives:

This study was carried out to assess the role of VEGF and its receptor in retinopathy of prematurity.

Patients and Methods:

Around 200 preterm infants born in SSK hospital were screened at 33 - 34 weeks. These babies were followed up according to the international classification of retinopathy of prematurity (ICROP) criteria. Those infants who developed ROP at 38 - 40 weeks were enrolled in group A while an equal number of infants who did not develop ROP were included in group B. Each group comprised of 30 subjects each. Venous sampling was carried out twice, once at 33 - 34 weeks and then again at 38 - 40 weeks. VEGF and VEGF-R2 were estimated by commercially available ELISA kits.

Results:

There was no statistically significant difference between the levels of VEGF and VEGF-R2 in both groups at first visit as well as the follow up visit. However, the intra-group difference was significant between the first and the final visit in VEGF and VEGF-R2 levels in the cases with ROP. In the control population, the VEGF levels were significantly lower in the follow up visit as compared to the initial visit.

Conclusions:

Our study demonstrates that a significant difference is seen in the serum VEGF and VRGF-R2 in the second visit of the infants with ROP demonstrating that VEGF might be responsible for the initiation and aggravation of ROP.

Maternal Iron Deficiency Anemia as a Risk Factor for the Development of Retinopathy of Prematurity

BACKGROUND

Retinopathy of prematurity is a proliferative vascular disease affecting premature newborns and occurs during vessel development and maturation. The aim of this study was to evaluate the maternal iron deficiency anemia as possible risk factors associated with the development of retinopathy of prematurity among premature or very low birth weight infants.

METHODS

In this study, mothers of 254 infants with retinopathy of prematurity were analyzed retrospectively, and their laboratory results of medical records during pregnancy were reviewed for possible iron deficiency anemia.

RESULTS

In a cohort of 254 mothers of premature infants with retinopathy of prematurity, 187 (73.6%) had iron deficiency, while the remaining 67 (26.4%) mothers had no deficiency. Babies born to mothers with iron deficiency anemia with markedly decreased hemoglobin, hematocrit, mean corpuscular volume, serum iron, and ferritin levels were more likely to develop retinopathy of prematurity.

CONCLUSIONS

Our results are the first to suggest that maternal iron deficiency is a risk factor for the development of retinopathy of prematurity. Our data suggest that maternal iron supplementation therapy during pregnancy might lower the risk of retinopathy of prematurity.

Natural history of retinopathy of prematurity: two-year outcomes of a prospective study

PURPOSE

To investigate the 2-year outcomes of the natural history of retinopathy of prematurity (ROP) in Taiwan.

METHODS

A prospective study was conducted at two tertiary medical centers. Premature infants were screened and examined for ROP. The postmenstrual ages of developing each stage of ROP and the associated risk factors were recorded.

RESULTS

A total of 698 infants were included. The incidences of ROP and treatment-requiring ROP in all patients with ROP were 29.7% and 37.2%. When only including patients with birth weight of 1,250 g or less, the incidences were 62.2% and 39.1%, respectively. In patients with ROP with birth weight over 1,250 g, 25% of them developed treatment-requiring ROP. The median postmenstrual ages for the development of Stage 1, Stage 2, and Type 1 ROP were 33.0, 34.0, and 34.7 weeks, respectively. Gestational age at birth and birth weight were the most important factors associated with treatment-requiring ROP (hazard ratios of 0.3 and 0.6).

CONCLUSION

Our hospital-based study reveals an earlier postmenstrual age of developing ROP in this Asian population than in the Early Treatment for ROP study. Infants with birth weight over 1,250 g could still develop treatment-requiring ROP. Suboptimal oxygen control, different genetic dispositions among different races, inconsistencies in ROP diagnosis, and earlier screening might account for such a phenomenon.

Association of Maternal Age to Development and Progression of Retinopathy of Prematurity in Infants of Gestational Age under 33 Weeks

Aim. To find predictive and indicative markers of risk for development of retinopathy of prematurity (ROP) and its progression to the stage requiring laser treatment, in premature infants whose gestational age (GA) was under 33 weeks. Methods. We retrospectively reviewed medical records of 197 premature infants born in 2005-2010 whose GA < 33 weeks and underwent eye screening at Keio University Hospital. The association between candidate risk factors and development or progression of ROP was assessed. Results. Among the 182 eligible infants (median GA, 29.1 weeks; median birth weight (BW), 1028 g), 84 (46%) developed any stage of ROP, of which 45 (25%) required laser treatment. Multivariate analysis using a stepwise method showed that GA (P = 0.002; 95% confidence interval (CI), 0.508-0.858), BW (P < 0.001; 95% CI, 0.994-0.998), and lower maternal age (P = 0.032; 95% CI, 0.819-0.991) were the risk factors for ROP development and GA (P < 0.001; 95% CI, 0.387-0.609) and lower maternal age (P = 0.012; 95% CI, 0.795-0.973) were for laser treatment. The odds ratio of requiring laser treatment was 3.3 when the maternal age was <33 years. Conclusion. ROP was more likely to be developed and progressed in infants born from younger mother and low GA.

Neonatal intensive care unit-specific screening criteria for retinopathy of prematurity

This study investigated the incidence of retinopathy of prematurity (ROP) and its risk factors in a tertiary referral hospital in Taiwan to evaluate the applicability of the ROP screening guidelines published by the American Academy of Pediatrics, American Academy of Ophthalmology, and American Association for Pediatric Ophthalmology and Strabismus in 2006 (2006 guidelines). A pediatric ophthalmologist applied the 2006 guidelines to screen for ROP and to treat with laser photocoagulation in each case. We retrieved all records of premature infants referred for ROP screening at the hospital during 2004 to 2008. Univariate logistic regression analysis was applied firstly to identify factors correlating with stage 3 ROP or with laser treatment, and then those significant (p < 0.05) risk factors were analyzed by multivariate logistic regression. In the 138 male and 118 female premature infants in this study, mean gestation age was 30.8 ± 2.8 weeks, and mean birth weight was 1464.7 ± 434.2 g. The percentage of infants with ROP in at least one eye was 38.7%. Thirty two (12.5%) had ROP stage 3 or higher in at least one eye. Multivariate logistic regression analysis showed that the best predictors of type 1 pre-threshold ROP (requiring laser treatment) were young gestational age, low birth weight and male gender. As medical care of extremely premature infants improves, timely identification and treatment of conditions such as ROP are essential. Although the incidence of ROP in this institute was comparable to that in developing countries and higher than that in developed countries, the 2006 guidelines originally developed for a United States population were still applicable. However, the 2006 guidelines should be modified for a Taiwan population by considering gender.

Retinopathy of prematurity in southern Taiwan: a 10-year tertiary medical center study

BACKGROUND/PURPOSE

Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. This retrospective study investigated ROP, including incidence, demographic information,risk factors, treatments, and refractive outcomes, in southern Taiwan over a 10-year period.

METHODS

The authors retrieved the National Cheng Kung University Hospital database between the years 2000 and 2009 for newborns with a gestational age less than 32 weeks and/or with a birth weight less than 1500 g who had been screened for ROP. We recorded sex, birth weight, gestational age, in-hospital versus out-of-hospital birth, paternal and maternal ages, whether there were multiple gestations, parity, Apgar scores, length of hospital stay, risk factors, presence and severity of ROP and whether it was treated, and refraction at the last visit. Regression analyses were performed to identify risk factors for ROP.

RESULTS

A total of 503 live births were included. ROP was identified in 190 (37.8%) and met criteria for treatment in 59 (11.7%).ROP was diagnosed as stage 1, 2, 3, 4, and 5 in 61 (12.1%), 36 (7.2%), 81 (16.1%), 11 (2.2%), and 1 (0.2%) infant, respectively. Lower birth weight and younger gestational age were risk factors for greater severity of ROP (p < 0.001). Of the 167 with extremely low birth weight (<1000 g), 118 (70.7%) had ROP and 49 (29.3%) required treatment. On univariate analysis, low birth weight, younger gestational age, and risk factors such as respiratory distress syndrome, chronic lung disease, patent ductus arteriosus, surfactant usage, indomethacin usage, sepsis, upper gastrointestinal bleeding, blood transfusion, and necrotizing enterocolitis were associated with ROP. Multivariate logistic regression analysis showed that only lower birth weight was a significant and independent risk factor for ROP. Myopia (76%)and anisometropia (28%)were common in advanced ROP.

CONCLUSION

Low birth weight is a major risk factor for ROP. Infants with extremely low birth weight had a higher risk of severe ROP. Common ocular sequelae of advanced ROP were myopia and anisometropia.

Low gestational age and chronic lung disease are synergistic risk factors for retinopathy of prematurity

AIMS

This retrospective, population based study was designed to investigate risk factors for development of retinopathy of prematurity (ROP) and their possible interrelationships, in neonates of gestational age (GA) <32 weeks born in a well-defined geographical region. STUDY DESIGN-SUBJECTS: The study population included all preterm infants born alive with GA 24-32 weeks in Northwestern Greece during a 9-year period and hospitalised in the regional neonatal intensive care unit (NICU).

OUTCOME MEASUREMENTS

The association was assessed of the presence of ROP with maternal factors: age, pathology of pregnancy, in-vitro fertilisation, multiple gestation, mode of delivery, perinatal factors: gender, antenatal steroids, transportation, resuscitation, GA, birth weight (BW), small for GA status and postnatal morbidity: chronic lung disease (CLD), intraventricular haemorrhage (IVH), necrotizing enterocolitis (NEC), respiratory distress syndrome (RDS), maximum O(2) needs, hypoxic/hyperoxic episodes, patent ductus arteriosus (PDA), sepsis, using multiple logistic regression analysis.

RESULTS

Of 189 infants without congenital anomalies born at GA 24-32 weeks ROP was diagnosed in 24 (12.7%) (>grade 2: 6). Logistic regression analysis showed ROP to be strongly associated with GA, odds ratio (OR) 2.1, confidence interval (CI) 1.3-3.3, p<0.01 and CLD, OR 10.2, CI 2.3-44, p<0.01, respectively, independent of confounding factors. By estimating interaction on an additive scale it was shown that the combined risk effect of GA and CLD was larger than the sum of the individual risk effects, implying synergistic effect.

CONCLUSIONS

ROP was closely and independently related to both low GA and the diagnosis of CLD, which were interrelated in the development of ROP.

Effects of maternal and placental inflammation on retinopathy of prematurity

PURPOSE

To identify maternal and placental risk factors for the occurrence and progression of retinopathy of prematurity (ROP).

METHODS

This was a retrospective cohort study. The study cohort consisted of 246 infants with gestational age ≤ 32 weeks, with histologic examinations of their placentas. Medical records of eligible preterm infants were retrospectively reviewed. A regression model was constructed with control for known or potential factors associated with ROP. Occurrences of ROP, severe ROP (≥ stage 3), and clinically significant ROP requiring laser treatment were assessed.

RESULTS

ROP was diagnosed in 82 of 246 infants (33.3%), including 49 with mild ROP and 33 with severe ROP. Laser treatment was performed on 27 infants (11%: 27/246). Multivariate regression analysis indicated clinical chorioamnionitis and elevated maternal WBC count on admission to be associated with ROP occurrence [odds ratio (OR) = 4.370, P = 0.046; and OR = 1.104 per 1,000 cells/mm(3) incremental increase, P = 0.019, respectively], while the use of tocolytics was associated with reduced occurrence of ROP (OR = 0.278, P = 0.006). Elevated maternal WBC count on admission was also independently associated with ROP progression requiring laser treatment (OR = 1.171 per 1,000 cells/mm(3) incremental increase, P = 0.026). However, neither histologic chorioamnionitis nor funisitis was associated with the occurrence or progression of ROP.

CONCLUSIONS

Clinical chorioamnionitis and elevated maternal WBC count, but not histologic chorioamnionitis, were significantly and independently associated with ROP. These findings support the hypothesis that maternal systemic inflammation may play a role in the pathogenesis of ROP.

Current update on retinopathy of prematurity: screening and treatment

PURPOSE OF REVIEW

Despite current treatments, retinopathy of prematurity (ROP) remains a major cause of blindness in premature infants and the incidence is increasing with increased survival of infants born at very early gestational ages. This review summarizes the recent literature on ROP with a special focus on recent advances in treatment options as well as newly developed methods for disease screening.

RECENT FINDINGS

Genetic studies find a genetic predisposition to ROP-linking genes in the Wnt pathway with development of severe ROP. With regard to diagnosis, a new screening method has been developed that allows prediction of ROP risk based on postnatal body weight gain alone. Formerly weight gain postnatally in combination with insulin-like growth factor levels was found to predict treatable ROP. New treatment options for severe cases of ROP have been proposed targeting vascular endothelial growth factor (VEGF). Whether anti-VEGF treatment is well tolerated in preterm infants, however, has to be further evaluated in controlled clinical trials. Finally, new reports from the early treatment ROP group suggest that early laser treatment for type 1 but not type 2 high-risk prethreshold ROP improves visual acuity outcomes at 6 years of age.

SUMMARY

With the increasing survival of premature infants and increased incidence of ROP, it is important to screen for ROP risk and treat at-risk patients in a timely manner to preserve their visual function and reduce complications.