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Blindness is decreasing among children born preterm during the last four decades in Denmark
Hajer A Al-Abaiji1, Kamilla Nissen1, Carina Slidsborg1
1Department of Ophthalmology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark.
Insights
Visual impairment (VI) in preterm children has decreased significantly over four decades. While blindness from prematurity is nearly eliminated, non-ocular causes and comorbidities remain a concern for these vulnerable infants.
Area of Science:
- Ophthalmology
- Neonatology
- Pediatrics
Background:
- Preterm birth is a known risk factor for visual impairment (VI).
- Advances in neonatal care have improved survival rates for extremely preterm infants, potentially altering the spectrum of associated morbidities.
- Understanding temporal trends in VI among ex-preterm populations is crucial for public health initiatives.
Purpose of the Study:
- To analyze the prevalence and causes of visual impairment in a Danish ex-preterm population over the past 40 years.
- To identify changes in the spectrum of VI causes and associated comorbidities.
- To assess the impact of improved neonatal intensive care and retinopathy of prematurity management.
Main Methods:
- Utilized the National Register of Blind and Visually Impaired Children (NRVIC) in Denmark.
- Included ex-preterm infants born before 32 weeks gestational age between 1988 and 2020.
- Analyzed temporal changes in the main cause of VI, severity of VI, and systemic comorbidities.
Main Results:
- Prevalence of VI decreased from 26/1000 in the 1980s to 15/1000 in the 2000s.
- Blindness due to prematurity is now rare (1/1000).
- Sequelae of retinopathy of prematurity (ROP) decreased as a cause of VI (51% to 34%), while non-ocular causes increased (1% to 36%).
- Comorbidities were present in 64% of cases.
Conclusions:
- Improved neonatal intensive care and ROP management have significantly reduced severe VI and blindness in ex-preterm children.
- Non-ocular causes of VI and comorbidities remain significant risks for preterm infants.
- Continued vigilance and research into non-ocular VI causes are essential for this population.
Purpose:
Children born preterm are believed to be at increased risk of visual impairment (VI). The increased survival rate of extremely preterm children may have changed the spectrum of diseases occurring postnatally. The aim of this study was to analyse the prevalence and causes of VI in an ex-preterm Danish population during the last 4 decades.
Methods:
The study was based on the National Register of Blind and Visually Impaired Children (NRVIC). Ex-preterms born at gestational age (GA) <32 weeks and enrolled in NRVIC at any time between 1988 and 2020 were included. The main cause of VI, the severity of VI and systemic comorbidities were analysed for temporal changes.
Results:
A total of 335 patients were included. The prevalence of VI decreased from 26/1000 preterm children in the 1980s to 15/1000 in 2000s. Blindness due to preterm birth is almost eliminated affecting 1/1000 today. Sequelae to retinopathy of prematurity (ROP) was the most common cause of VI (51% of cases) in the 1980s but decreased to 34% in 2010s, whereas non-ocular causes of VI increased from 1% to 36%, respectively. More than half of the children (64%) had combined comorbidities and 36% had isolated VI.
Conclusion:
The improved monitoring in neonatal intensive care units and management of ROP has reduced the prevalence of severe VI due to ROP and almost eliminated blindness over the last decades in Denmark. However, preterm children are still at risk of non-ocular causes of VI and comorbidities following the premature delivery.
