Retinopathy of prematurity, a decrease in frequency and severity. Trends over 16 years in a Danish county

Purpose: To analyse the trends over 16 years (1982-97) in a Danish county regarding the clinical appearance of retinopathy of prematurity (ROP), Methods: The data for birth years 1993-97 regarding the regular ophthalmic surveillance for ROP in the region have been analysed. With gestational age (GA) 32 weeks and/or a birthweight (BW) 1750 g as attempted screening limits a total of 177 premature infants were surveyed. Comparison was made with studies of a similar set-up from the preceding four 3-year periods comprising a total of 814 subjects. Results: The number of survivors regarded at a higher risk of developing ROP (GA and BW both <32 weeks/1750 g, n = 478) showed an even increase over the five investigation periods. The ROP frequency, however, fell from a level of 39% to 10%, there were fewer with severe sequels to ROP, and the children surveyed 'above limits' eventually avoided ROP, Conclusions: Using the ROP profile as a yardstick for the quality of the neonatal service given to the most immature newborns over the period 1982-97, the risk limits regarding GA and BW have gone down. More and more of the heavier preterm babies now escape ROP. A significant decrease in frequency of ROP in the more immature groups has been observed, and fewer cases have progressed to visual impairment.