title: Association between Exposure to Smartphones and Ocular Health in Adolescents.
abstract: Smartphone use has dramatically increased in recent years. Smartphones may have adverse health effects, particularly on the eyes, because users stare at the screen for a much longer time than they do with ordinary mobile phones. The objective of this study was to elucidate the relationship between smartphone use and ocular symptoms among adolescents.
  
  
  
  Information on smartphone use and ocular symptoms (blurring, redness, visual disturbance, secretion, inflammation, lacrimation and dryness) related to eye fatigue and strain from 715 adolescent subjects from three cities in Korea was obtained using a structured questionnaire. Ocular health was scored using number of ocular symptoms. Odds ratios (ORs), 95% confidence intervals (95% CIs) and p-values for ocular symptoms were calculated with binomial and multinomial logistic regression models.
  
  
  
  Higher prevalence rates for ocular symptoms were observed in groups with greater exposure to smartphones (p < 0.05). Longer daily smartphone use was associated with a higher likelihood of having multiple ocular symptoms (5-7 symptoms out of 7 symptoms; p = 0.005). Excessive/intermittent use (>2 hours daily and ≤2 hours continuously) and excessive/persistent use (>2 hours daily and >2 hours continuously) compared to shorter use (<2 hours daily) were associated with multiple ocular symptoms (OR 2.18, 95% CI 1.09-4.39; OR 2.26, 95% CI 1.11-4.57, respectively). A higher lifetime exposure to smartphones was associated with a higher likelihood of having multiple ocular symptoms (OR 3.05, 95% CI 1.51-6.19; p = 0.001).
  
  
  
  Increasing exposure to smartphones can have a negative impact on ocular health in adolescents.
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Joowon
authors.initials: J
authors.lastname: Kim
authors.affiliation: b Department of Preventive Medicine , Seoul National University College of Medicine , Seoul , Korea.|c Cancer Research Institute, Seoul National University , Seoul , Korea.|d Department of Biomedical Science , Seoul National University Graduate School , Seoul , Korea.
authors.forename: Yunji
authors.initials: Y
authors.lastname: Hwang
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Seungheon
authors.initials: S
authors.lastname: Kang
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Minhye
authors.initials: M
authors.lastname: Kim
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Tae-Shin
authors.initials: TS
authors.lastname: Kim
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Jay
authors.initials: J
authors.lastname: Kim
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Jeongmin
authors.initials: J
authors.lastname: Seo
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Hyojeong
authors.initials: H
authors.lastname: Ahn
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Sungjoon
authors.initials: S
authors.lastname: Yoon
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Jun Pil
authors.initials: JP
authors.lastname: Yun
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Yae Lim
authors.initials: YL
authors.lastname: Lee
authors.affiliation: a Seoul National University College of Medicine , Seoul , Korea.
authors.forename: Hyunsoo
authors.initials: H
authors.lastname: Ham
authors.affiliation: e Department of Ophthalmology , Seoul National University , Seoul , Korea.
authors.forename: Hyeong Gon
authors.initials: HG
authors.lastname: Yu
authors.affiliation: b Department of Preventive Medicine , Seoul National University College of Medicine , Seoul , Korea.|c Cancer Research Institute, Seoul National University , Seoul , Korea.|d Department of Biomedical Science , Seoul National University Graduate School , Seoul , Korea.
authors.forename: Sue K
authors.initials: SK
authors.lastname: Park
mesh_terms: D000293:Adolescent; D005260:Female; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D000068997:Smartphone / Q000706:statistics & numerical data*; D014786:Vision Disorders / Q000453:epidemiology* / Q000209:etiology
keywords: Adolescent; computer vision syndrome; lifetime exposure; ocular symptoms; smartphone