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Increased hyperopia with ageing based on cycloplegic refractions in adults: the Tehran Eye Study.
H Hashemi1, R Iribarren, I G Morgan
1Epidemiology and Biostatistics Department, School of Public Health, Tehran University of Medical Sciences, Postal Box 14155-6446, Tehran, Iran.
The British Journal of Ophthalmology
|August 21, 2009
Summary
The prevalence of hyperopia increases significantly with age in Tehran, Iran, particularly after age 35. This population-based study highlights age as a key factor in hyperopic shifts.
Area of Science:
- Ophthalmology
- Public Health
- Epidemiology
Background:
- Hyperopia prevalence and its age-related trends are not well-established in many populations.
- Understanding these trends is crucial for public health planning and vision care.
Purpose of the Study:
- To investigate the prevalence and age-specific trends of hyperopia in the adult population of Tehran, Iran.
- To identify factors associated with hyperopia in this demographic.
Main Methods:
- A population-based, stratified random cluster sample of individuals aged 5 years and older in Tehran.
- Cycloplegic autorefraction was performed 30 minutes after instillation of cyclopentolate eye drops.
- Prevalence rates were calculated for various hyperopia cut-off points (≥+0.5, +1.0, +2.0, +3.0 D) and stratified by age.
Main Results:
- The prevalence of hyperopia (spherical equivalent ≥+0.5 D) was 56.6%, with rates of 28.1% (≥+1.0 D), 6.3% (≥+2.0 D), and 2.2% (≥+3.0 D).
- Hyperopia prevalence was lowest in the 25-35-year age group and increased significantly with age up to 70 years.
- Multivariable analysis indicated that age was the only significant predictor of hyperopia, out of age, gender, diabetes, and cataract.
Conclusions:
- This study provides the first population-based evidence in Tehran demonstrating a clear increase in hyperopia with advancing age, using cycloplegic refraction.
- The findings suggest that age-related changes in refraction, leading to hyperopic shifts, are primarily driven by factors other than a small contribution from decreased accommodation.
- Further research is warranted to elucidate the underlying mechanisms responsible for the age-related hyperopic shift in refractive error.
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