This is a common belief, but intermittent catheterization is not directly correlated with age. There are many reasons why someone may need to use intermittent catheters but "old age" is not one of them.
Sometimes it’s due to a physical problem. Sometimes it’s because of a problem related to brain signals, known as ‘neurogenic bladder’. There are a range of conditions, but intermittent catheters are recommended to help take back control from urinary incontinence - regardless of age. For some intermittent catheter users it's only for a short time and for some it's for life.