%0 Journal Article %T Blepharoptosis and cognitive performance: a population-based study of 1.4 million adolescents. %A Nitzan I %A Derazne E %A Afek A %A Gur Z %A Weinstein O %A Twig G %A Zloto O %J Eur J Pediatr %V 183 %N 1 %D 2024 Jan 23 %M 37870609 %F 3.86 %R 10.1007/s00431-023-05294-5 %X The purpose of this study is to examine the association between blepharoptosis and cognitive performance in late adolescence. This population-based, retrospective, cross-sectional study included 1,411,570 Israeli-born adolescents (620,107 women, 43.9%) aged 16-19 years who were medically examined before compulsory military service between 1993 and 2017. The diagnosis of blepharoptosis was verified by an ophthalmologist. Cognitive performance was assessed by a validated intelligence-quotient-equivalent test, comprising four domains (problem-solving, verbal abstraction and categorization, verbal comprehension, and mathematical abilities). Cognitive Z-scores were calculated and categorized as high (≥ 1 standard deviation (SD)), medium (- 1 to < 1 SD), and low (less than - 1 SD). Relationships were analyzed using regression models adjusted for sociodemographic variables including sex, year of birth, residential socioeconomic status, education level, body mass index, and familial country of origin. A total of 577 (41 per 100,000, 32.2% women) adolescents were diagnosed with blepharoptosis. The proportions of unilateral and bilateral visual impairment among adolescents with blepharoptosis were 13.0% and 3.5%, respectively. In a multivariable analysis, blepharoptosis was associated with a 0.18 SD reduction in cognitive Z-score (p < 0.001). The adjusted odds ratios for low and high cognitive Z-scores in adolescents with blepharoptosis were 1.54 (1.25-1.89) and 0.80 (0.62-1.04), respectively. This relationship persisted when adolescents with normal best-corrected visual acuity or unimpaired health status were analyzed separately.  Conclusions: Blepharoptosis is associated with reduced cognitive performance determined in late adolescence. Future prospective studies should investigate the causes of this link and their underlying mechanisms. What is Known: • While earlier investigations have examined the effects of blepharoptosis on vision and quality of life, the association between blepharoptosis and cognitive outcomes in youth has remained unexplored. What is New: • This nationwide study involving 1.4 million Israeli adolescents found a correlation between blepharoptosis and reduced cognitive performance. • Our findings suggest a potential interplay between blepharoptosis and cognitive development in the pediatric population, calling for increased focus on the educational needs of affected individuals.