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Binocular Dynamic Visual Acuity in Eyeglass-Corrected Myopic Patients
Published on: March 29, 2022
Passive smoking exposure might be associated with hypermetropia
1Ophthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt. shazlyamany@yahoo.co.uk
Summary
Children exposed to passive smoking showed higher levels of nicotine metabolites, correlating with refractive error. Specifically, hypermetropia was linked to increased passive smoking exposure in children.
Area of Science:
- Ophthalmology
- Environmental Health
- Pediatrics
Background:
- Childhood refractive errors are a significant public health concern.
- Passive smoking is a widespread environmental exposure with known health risks.
- The impact of passive smoke exposure on pediatric eye development requires further investigation.
Purpose of the Study:
- To investigate the association between passive smoking and refractive errors in children.
- To quantify nicotine exposure in children through urinary cotinine levels.
- To determine if passive smoke exposure influences the type or degree of refractive error.
Main Methods:
- A cohort of 300 children aged 5-12 years underwent ophthalmological examinations, including cycloplegic refraction.
- Detailed history on parental smoking and passive smoke exposure was collected.
- Urinary cotinine levels, normalized by creatinine, were measured to assess nicotine exposure.
Main Results:
- Refractive error distribution: 40.7% hypermetropic, 28.7% myopic, 30.7% emmetropic.
- Higher urinary cotinine levels and cotinine/creatinine ratio (CCR) were observed in hypermetropic children compared to myopic and emmetropic children.
- Significant correlations were found between spherical equivalent refractive error and parental smoking, CCR, and urinary cotinine levels.
Conclusions:
- Passive smoking indices, including urinary cotinine and CCR, are associated with the degree of refractive error in children.
- Children with hypermetropia exhibited significantly higher passive smoking exposure markers.
- Findings suggest a potential link between passive smoking and a refractive error shift towards hypermetropia in children.
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