Can Keratoconus Progress After Age 40?
By Dr. Adel Barbara, MD, FRCOphth — Ophthalmologist, Cornea & Refractive Surgery
Last medically reviewed: September 2026
Keratoconus often progresses more slowly as people age, but it does not automatically stop at 40. Stability should be demonstrated by clinical evidence rather than assumed from age alone.
Why does age matter?
Natural corneal stiffening may reduce the tendency to change over time. Population data nevertheless show that progression can occur later, particularly when there are new refractive or visual changes.
Signs that require review
- A changing prescription or increasing astigmatism.
- Reduced corrected vision.
- New distortion, glare or contact-lens intolerance.
- Consistent change in anterior or posterior tomography or thickness profile.
Does change always require CXL?
No. Scan quality, dry eye and contact-lens wear can affect measurements. When true progression is confirmed, CXL may be considered after 40 if the cornea is medically suitable.
Professional sources
General information only.
