Presbyopia

Pathophysiology

The American Medical Association suggests that presbyopia occurs as part of the natural aging process when the crystalline lens loses its ability to change shape and focus on near objects, resulting from age-related loss of lens flexibility beginning around age 45 years 1, 2, 3
Loss of lens flexibility and increased lens stiffness prevents adequate accommodation for near vision, according to the American Medical Association 1, 2, 4

The American Medical Association states that presbyopia typically begins affecting individuals around age 40-45 years and progresses thereafter, with the prevalence of presbyopia increasing with age 1, 2, 4
By age 55, most individuals require some form of near vision correction, as reported by the American Medical Association 1, 2

Myopia (nearsightedness) causes difficulty seeing distant objects, not near objects, and its prevalence actually decreases with age, as noted by the American Medical Association 1, 2
Hyperopia (farsightedness) can affect near vision but is not specifically caused by decreased lens compliance, according to the American Academy of Ophthalmology 1, 5
Astigmatism results from irregular corneal or lenticular curvature, not decreased lens compliance, as reported by the American Academy of Ophthalmology 5, 6
Emmetropia is the absence of refractive error (normal vision), as defined by the American Academy of Ophthalmology 5, 6