How does age affect kidney function?

Age can negatively impact kidney function, leading to a gradual decline in its ability to filter waste from the blood.

As we age, our bodies undergo various physiological changes, and the kidneys are no exception. The kidneys are responsible for filtering waste products from the blood, maintaining fluid and electrolyte balance, and regulating blood pressure. However, with age, the number of functioning nephrons (the filtering units of the kidney) decreases. This reduction in nephrons can lead to a decrease in the overall filtering capacity of the kidneys.

Additionally, the blood vessels supplying the kidneys can become hardened or damaged over time, a condition known as atherosclerosis. This can reduce the blood flow to the kidneys, impairing their ability to function effectively. The kidneys' ability to concentrate urine and conserve water also decreases with age, leading to increased frequency of urination, especially at night.

Furthermore, the ageing process can affect the kidneys' ability to regulate the balance of acids and bases in the body. This can lead to a condition called metabolic acidosis, where there is too much acid in the body fluids. Age-related changes in the endocrine system can also affect the kidneys' ability to respond to hormones that help regulate blood pressure and fluid balance.

Lastly, the ageing immune system may not respond as effectively to infections, including urinary tract infections, which can further compromise kidney function. Age-related changes in the urinary system, such as an enlarged prostate in men or bladder prolapse in women, can also lead to urinary retention and increase the risk of kidney infections and damage.

In summary, age can affect kidney function in several ways, including a reduction in the number of functioning nephrons, damage to the blood vessels supplying the kidneys, changes in the body's acid-base balance, and an increased risk of infections.