Abstract
Purpose :
To investigate the effect of baseline choroidal thickness and axial length on axial growth after 5-year follow-up of 730 children aged 11-years.
Methods :
The Copenhagen Child Cohort 2000 (CCC2000) eye study is a prospective, population-based observational study where 741 Danish children have been examined at 11 years of age and at 16 years of age with best corrected visual acuity (ETDRS), non-cycloplegic refraction, ocular biometry and enhanced depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT). Eight children were excluded due to a best corrected visual acuity < 80 ETDRS letters and 3 due to missing axial length measurements when aged 11 years.
Results :
We analysed data from rights eyes of 730 children (44.3% boys, 55.7% girls). The mean (± SD) age at baseline was 11.6 (± 0.38) years and 16.6 (± 0.26) years at follow-up and the mean follow-up interval was 4.99 (±0.38) years. The mean axial length was 23.16 ± 0.80 mm at baseline and 23.47 ± 0.90 mm at follow-up. The mean growth rate in axial length was 61.3 µm/year (± 47.4 µm/year, median 49.6 µm/year, upper range 346 µm/year) with no difference between boys and girls (p=0.26).
Eyes in the upper (23.5-26.9 mm) and the middle tertile of axial length at baseline grew 25.3 µm/year (95% CL (16.5 to 34.2), p<0.0001) and 10.6 µm/year (95% CL (2.2 to 19.1), p=0.0140) faster than eyes in the lower tertile of axial length (20.1-22.8 mm), respectively, adjusted for age at follow-up and gender.
Choroidal thickness at 11-years of age did not predict growth rate in axial length in neither the crude analyses, when adjusting for axial length, or when stratifying the analysis on axial length tertiles at 11-years of age.
Conclusions :
In the CCC2000 cohort, having a longer eye at 11 years of age was associated with an increased axial length elongation over the next 5 years. There was no detectable effect of baseline choroidal thickness on subsequent change in axial length.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.