Lesson 1, Topic 1
In Progress

Changes in Anatomy, Physiology, and Diseases of the Urinary and Reproductive Systems

April 11, 2024

Learning Objective: Examine the changes in anatomy, physiology, and diseases of the urinary and reproductive systems.
      TABLE 30.7 summarizes the changes to the urinary and reproductive systems and what can be done to promote healthy aging. The following sections provide more detail about the changes to those systems.


Urinary System
Learning Objective: Explain the changes in the anatomy and physiology of the urinary system caused by aging.
      As the body ages, structural changes in the kidneys cause the urinary system to become less efficient. Between the ages of 40 and 80, the kidney loses about 20% of its mass. The number of functional nephron units decreases. Blood flow to the kidneys is reduced because of a decrease in cardiovascular efficiency. Because of the reduced blood flow to the kidneys and the decreased number of nephrons, the kidneys become less efficient at filtering waste from the blood. This results in a more diluted, less concentrated urine. The kidneys require more water to excrete the same amount of waste. Medication takes longer to be removed from the body. Older adults are at increased risk for toxic levels of medication in the bloodstream because of this reduced filtration rate.
      Fibrous connective tissue replaces the smooth muscle and elastic tissue in the bladder. This thickening of the bladder wall reduces the bladder’s ability to expand. The bladder’s capacity to store fluid comfortably is reduced from 400 to 250 mL. These structural changes lead to increased frequency of urination and urinary retention. Older adults are at increased risk of urinary tract infections because of residual urine. Sleep is interrupted by the need to void during the night. The sensation of bladder fullness is not recognized as quickly by the older brain. Reduced time between awareness of the need to void and involuntary urination can cause anxiety. Often, older adults reduce their fluid intake to prevent possible embarrassment. Unfortunately, this causes dehydration and an increased risk of urinary tract infections. Another change is the loss of muscle tone in the urethra. In addition, the pelvic floor muscles in an aging woman relax due to decreased estrogen levels or previous pregnancy and childbirth.
      Despite these changes, the kidneys have great reserve capacity and are able to continue functioning normally. Urinary incontinence, the involuntary loss of urine, is a significant problem for aging patients but is not a normal part of the aging process. Changes in the urinary system make older people more vulnerable to incontinence, but factors such as infection, confusion, difficulty with mobility, and side effects of medications contribute to the development of the problem. Incontinence is both an emotional and a physical problem. To avoid the risk of an embarrassing accident, people with this problem may avoid social occasions or activities they enjoy. Often people are too embarrassed to admit they have this condition or believe it is just part of aging. Once the condition has been diagnosed by a urologist, pelvic floor muscle exercises, medication, or surgery may be recommended.

Reproductive System
Learning Objective: Explain the changes in the anatomy and physiology of the reproductive system caused by aging.
      Aging brings a decrease in circulating levels of the female hormones estrogen and progesterone, whereas androgen levels increase. The results of this decrease are changes in the genital tract. The vagina diminishes in width and length and becomes less elastic. The cervix, uterus, and ovaries decrease in size. Vaginal secretions decline; therefore, lubrication diminishes, resulting in vaginal dryness. Bacterial or yeast infections may occur because vaginal secretions are less acidic. Estrogen cream applied to vaginal tissue may be prescribed by the provider to help with dryness and thinning of the vaginal tissue. The patient should discuss the benefits and risks of estrogen replacement therapy with the provider to determine whether it should be used.
       Even though sperm production may decline in men over age 50, men remain virile well into old age. However, they experience a change in hormonal levels of testosterone, and these changes can affect the prostate gland. The prostate enlarges over time and presses down on the urethra, causing difficulty with urination. Surgery may be required to remove excess portions of the gland. Unfortunately, the operation may cause impotence, which can be treated medically with erectile dysfunction medications.
      Men experience some changes in sexual functioning as they age. It takes longer for the penis to become erect, longer for an orgasm to occur, and longer to recover. Direct stimulation may be required before an erection occurs, and when it does, it may be less firm than in younger years.
      Some drugs and illnesses can interfere with sexual function. Drugs used to control high blood pressure, antihistamines, antidepressants, and some stomach acid blockers, in addition to the diseases diabetes, arthritis, and arteriosclerosis, can have an adverse effect on sexual function. People who have had heart surgery or a heart attack are often concerned about sexual activity. Patients need to feel comfortable and should not be embarrassed to discuss their concerns openly with their providers. It is important for healthcare practitioners to dismiss the myth that older patients have lost the desire for and interest in sexual intercourse.