Which of the following is a common age-related change in renal function?

A common age-related change in renal function is a decrease in renal blood supply, leading to a decline in overall renal function. As individuals age, there are several physiological changes that occur within the kidneys. One significant change is the reduction in the number of functional nephron units, which can contribute to diminished renal mass. This decrease in nephron number and activity often results in reduced renal blood flow, further compromising kidney function.

While increased creatinine clearance would suggest improved renal function, aging generally leads to a gradual decline in both glomerular filtration rate (GFR) and creatinine clearance due to structural and functional changes such as glomerulosclerosis and tubular atrophy. The risk of developing renal adenocarcinoma may increase with age, but it is not classified as a common age-related change in renal function itself; instead, it is a disease risk factor rather than a functional change.

Thus, the correct response concerning the physiological and functional alterations that are typically seen with aging would be the decreased renal blood supply, which significantly impacts renal function over time.