The kidneys filter the blood and help remove wastes and extra fluid from the body. The kidneys also help control the body's chemical balance.
The kidneys are part of the urinary system, which also includes the ureters, bladder, and urethra.
Muscle changes and changes in the reproductive system can affect bladder control.
Aging Changes and Their Effects on the Kidneys and Bladder
As you age, your kidneys and bladder change. This can affect their function.
Changes in the kidneys that occur with age:
- Amount of kidney tissue decreases.
- Number of filtering units (nephrons) decreases. Nephrons filter waste material from the blood.
- Blood vessels supplying the kidneys can become hardened. This causes the kidneys to filter blood more slowly.
Changes in the bladder:
- The bladder wall changes. The elastic tissue becomes tough and the bladder becomes less stretchy. The bladder cannot hold as much urine as before.
- The bladder muscles weaken.
- The urethra can become blocked. In women, this can be due to weakened muscles that cause the bladder or vagina to fall out of position (prolapse). In men, the urethra can become blocked by an enlarged prostate gland.
In a healthy aging person, kidney function remains normal. But illness, medicines, and other conditions can affect kidney function.
Aging increases the risk of kidney and bladder problems such as:
- Bladder control issues, such as leakage or urinary incontinence (not being able to hold your urine), or urinary retention (not being able to completely empty your bladder)
- Bladder and other urinary tract infections (UTIs)
- Chronic kidney disease
When to Contact a Medical Professional
Call your health care provider right away if you have any of the following:
- Signs of a urinary tract infection, including fever or chills, burning when urinating, nausea and vomiting, extreme tiredness, or low back pain
- Very dark urine or fresh blood in the urine
- Trouble urinating
- Urinating more often than usual
- Sudden need to urinate (urinary urgency)
As You Grow Older, You Will Have Other Changes, Including:
- In the bones, muscles, and joints
- In the male reproductive system
- In the female reproductive system
- In organs, tissues, and cells
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Patel SR, Wiggins J. Renal and electrolyte disorders. In: Duthie EH, Katz PR, Malone ML, eds. Practice of Geriatrics. 4th ed. Philadelphia, PA: Elsevier Mosby; 2007:chap 44.
Smith PP, Kuche GA. Aging of the urinary tract. In: Fillit HM, Rockwood K, Woodhouse K, eds. Brocklehurst's Textbook of Geriatric Medicine and Gerontology. 7th ed. Philadelphia PA: Elsevier Saunders; 2010:chap 18.
Update Date 10/27/2014
Updated by: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.