I am trying to determine why my kidney function dropped to 45% from 49%, apparently in 3 months time. Also would like to know why, with intensive testing foir health problems over a two-year period, my function dropped to under 50% without it being noticed. Also trying to understand if this is normal with aging (I am 83), or if it signifies a more serious, possibly fatal, condition. I do not have the results of the blood testing that revealed the problem, but I can probably get them.