Johns Hopkins Health Alert
What Causes BPH?
If you experience a frequent urge to urinate, urinary incontinence, or intermittent urine flow, you may have an enlarged prostate or BPH – a common, non-cancerous condition affecting one in four men by age 55. What is BPH? Here is an explanation, in brief.
Although the cause of enlarged prostate hyperplasia (BPH) is not well understood, normal levels of testosterone and aging are essential for the development of the condition. Studies in dogs suggest that the female sex hormone estrogen may also play a role in BPH.
The word hyperplasia refers to any abnormal accumulation of cells that causes enlargement of a body part or organ. BPH occurs when an increase in the number of prostate cells produces discrete nodules in the prostate. The increase in nodules is due to a slowing of the normal rate of death of these cells, rather than to a heightened production.
Whether or not the resulting enlargement puts pressure on the urethra and increases resistance to urine flow depends on the location of the nodules. Although the transition zone accounts for only about 5 percent of the prostate mass, the nodules in men with BPH occur primarily in this region.
Because the transition zone directly envelops the urethra, excess tissue tends to obstruct urine flow. Contractions of the smooth muscle cells surrounding the nodules can also obstruct the urethra.
Consequently, some men with a very enlarged prostate may have no urethral obstruction, while others with mild enlargement may have marked symptoms because a nodule is located where it compresses the urethra, or because smooth muscles tighten. To compensate for urethral narrowing, the muscular wall of the bladder contracts more strongly to expel urine. These stronger contractions lead to a thickened bladder wall, which decreases the bladder's capacity to store urine.
Over time, the bladder holds smaller and smaller amounts of urine, resulting in a need to urinate more frequently. As the urethral obstruction worsens, the contractions can no longer empty the bladder completely. Urine retained in the bladder may then become infected or lead to the formation of bladder stones. Less often, the kidneys become damaged, either as a result of increased pressure on them from the overworked bladder or because an infection has spread from the bladder to the kidneys.
Posted in Enlarged Prostate on October 27, 2009
Reviewed September 2011
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What is the case when the person is in his early 30ies ? Does the frequency of having sex has any effect?
Posted by: Pedro | October 31, 2009 3:06 PM