Subjective Accommodative Function and Defocus Curve Metrics in Phakic Adults Aged 45-65 Years

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• Presbyopia, the age-related loss of accommodation, affects visual function in adults.
• Understanding changes in accommodative amplitude (AA), accommodative lag (LAG), and defocus curve (DC) is crucial for managing presbyopia.

Purpose of the Study:

• To evaluate accommodative amplitude (AA), accommodative lag (LAG), and defocus curve (DC) metrics in phakic adults aged 45-65 years.
• To investigate the relationships between these visual function metrics and age.

Main Methods:

• An observational cross-sectional study included 77 subjects aged 45-65, stratified into four age groups.
• Accommodative amplitude (AA) was measured using the push-up method.
• Accommodative lag (LAG) and monocular defocus curves (DC) were assessed using an open-field autorefractometer.

Main Results:

• Accommodative amplitude (AA) significantly decreased with age (p < 0.001).
• Accommodative lag (LAG) remained stable across all age groups (p > 0.27).
• Defocus curve (DC) metrics showed significant age-related declines, with reduced area under the curve (AUC) and less defocus cut-off in older groups (p < 0.001).

Conclusions:

• Accommodative amplitude (AA) and defocus curve (DC) metrics decline with age, while accommodative lag (LAG) remains stable.
• The weak association between these metrics suggests they capture distinct aspects of visual function.
• Defocus curve (DC) analysis provides valuable insights into functional near vision, complementing traditional accommodative measurements for presbyopia evaluation.