Fangfei Wei, Anke Raaijmakers, Zhen-Yu Zhang, Theun Pieter van Tienoven, Qi-Fang Huang, Wen-Yi Yang, Lutgarde Thijs, Harry Struijker-Boudier, Peter Verhamme, Karel Allegaert, and Jan Staessen
Background: The retinal microvasculature can be visualized noninvasively and mirrors the status of the cerebral vasculature. We therefore investigated in 93 prematurely born infants (birth weight < 1000 g) and 87 controls born at term whether neurocognitive performance at ∼11 years is associated with the diameter of retinal microvessels. Methods: We post-processed retinal photographs by a semi-automated software (Singapore I Vessel Assessment, version 3.6) and administered the Wechsler Non-Verbal test, Dutch version (Pearson, The Netherlands) to estimate the intelligence quotient (IQ) by combining matrix reasoning and spatial span. Results: Compared with the controls, cases had lower IQ (92.5 vs. 108.7; P < 0.001), smaller central retinal arteriolar (CRAE; 162.7 vs. 174.0 mm; P < 0.001) and venular (CRVE; 234.7 vs. 242.7 mm; P = 0.003) diameters and CRAE/CRVE ratio (AVR; 0.70 vs. 0.72; P = 0.002) and lower body mass index (17.0 vs. 17.7 kg/m2; P = 0.044), but higher mean arterial pressure (82.7 vs. 77.7 mmHg; P < 0.001). In all children, the effect sizes associated with a 1-SD increase in CRAE were +3.87 (P < 0.001), +1.80 (P = 0.004) and +2.26 (P = 0.003) for total IQ, matrix reasoning, and spatial span, respectively. In models adjusted for body mass index and mean arterial pressure, these estimates were +3.21 (P = 0.009), +1.57 (P = 0.020), and +1.84 (P = 0.024), respectively. The associations of IQ and matrix reasoning with AVR also attained significance (P ≤ 0.031). Conclusions: In conclusion, our findings suggest that underdevelopment of the microcirculation in prematurely born children might have lasting effects on their cognitive performance.