You may be suffering from presbyopia, an age-related refractive error that occurs to people in their 40s. There are certain vision changes related to age that you will begin to experience, such as the need for more light, difficulty reading and doing close work, glare, among others. These changes result from the natural lens inside your eye gradually thickening or hardening. It loses flexibility or elasticity over time. Age also causes changes in the muscle fibers around the lens so that the lens becomes less elastic, causing problems with focusing the eyes on close objects.