One of the most serious problems associated with BPH is called urinary retention. This means that a man can no longer pass urine, that his prostate has become so swollen that it has essentially blocked off his urine channel completely. This can be extremely painful. The normal male bladder holds approximately 400 ml or about 13 oz of urine. We see men in the emergency room with urinary retention who, when they have catheters placed, have more than a litre of urine (33 oz) in their bladders and this, as you can imagine, is excruciatingly painful. When a man is in urinary retention, he needs to have his urine drained, and this is most frequently accomplished with the placement of a catheter through the penis, via the prostate, into the bladder. The most common catheter used is known as the Foley catheter, but there are a variety of catheters that urologists have at their disposal to bypass the blockage. Sometimes a man can have such enlargement of the prostate that placing a catheter through the penis is impossible and he needs one placed through the abdominal wall, known as a suprapubic catheter. Most men who have histories of urinary retention are going to require some significant intervention, usually surgery, for their prostates. One of the more common causes of older men passing into urinary retention is the use of over-the-counter cold medicines, which cause over-contraction of the prostate and bladder neck. So be cautious using these medications if your prostate is enlarged.
Another problem that BPH causes is changes in the bladder muscle. We know that when the bladder is contracting against increased pressure at the level of the prostate, over the course of time, it will undergo hypertrophy (bulking up) and scarring (collagen deposition). This scarring is probably a major factor in the development of symptoms such as nocturia, frequency of urination and urgency. Most importantly, when the BPH is treated, whether medically or surgically, if a man has had long-standing prostate enlargement, then it is likely that these symptoms mentioned above, known as irritative symptoms, will remain even if the prostate no longer exists as a result of the irreversible structural changes in the bladder.
Yet another problem that men with very large prostates may experience is the development of bladder stones. The chronic obstruction causes failure to empty the bladder, minerals will deposit in the urine that is left behind in the bladder, and these will eventually form stones. These may require a surgical procedure to be removed or fragmented. Finally, in extreme cases, pressure build-up can get so great that kidney damage can occur. It is common for urologists to see men who have urinary retention who also have reduced kidney function, although this is generally reversible. However, if left unattended for a long enough period of time, the kidney function can be irreversibly damaged.
If you have symptoms consistent with LUTS, then a conversation with your physician is important. Much of what is done regarding BPH and LUTS is related to the patient’s “bother index.” How bothered is he? If a man has a very large prostate gland, has normal urinary function, does not have much nocturia and has normal kidney function, then no treatment may be the best course of action. However, for men with even mild enlargement of the prostate gland who have tremendous symptoms (for example, getting out of bed five times every night and going to the bathroom once every hour during the day) even with normal kidney function, even without bladder stones, or a history of urinary retention, a medical or surgical option may be appropriate. Surgical therapy is generally reserved for patients who have failed medical therapy.
III. Treatment of BPH/LUTS
Most patients who have BPH and LUTS are encouraged to limit their caffeine intakes as well as their alcohol intakes. Alcohol is a diuretic, and caffeine is a well recognized bladder-irritant. The first line treatment for BPH/LUTS is medication. There are two classes of drugs that are used for the treatment of BPH; the first is known as alpha-blockers (also known as alpha-adrenergic antagonists), and the second is known as 5–alpha reductase inhibitors. Alpha-blockers (Table 2) are drugs that have been around for many decades, but in their most current form are very effective treatments for BPH and LUTS. Drugs in this class include doxazosin (Cardura), terazosin (Hytrin), tamsulosin (Flomax) and alfuzosin (Uroxatral). These medications have a dual action in that they can reduce LUTS as well as treat a man’s blood pressure.The newer prostate drugs,such as Flomax and Uroxatal,have very little effect on blood pressure and are more specific to the prostate. The belief is that these medications work through reducing muscle tone in the prostate, bladder neck, and urethra. Interestingly, there are many men who have relatively small prostate glands who have tremendous symptoms, and it is proposed that this is not a mechanical obstruction in the sense that the prostate is not large enough to compress the urethra; however, the muscle tone inside the prostate is very high. These are patients who are generally highly sensitive to alpha-blocker therapy.
Another difference between the older (Hytrin, Cardura) and newer alpha-blockers (Flomax, Uroxatral) is that the older ones needed titration, that is, a tweaking of the dose in a sequential fashion to find the correct dose. This is not true for Flomax or Uroxatal. Approximately 60% of men with LUTS will have significant improvement in their symptoms with the use of alpha-blockers. These drugs typically act rapidly (in contrast to 5–alpha reductase inhibitors), but are associated with some side effects. These side effects include lethargy, nasal congestion and, with the older agents, blood pressure drop when the patient moves from a lying or sitting to a standing position (known as postural hypotension).
Another side effect that is worth noting is that they can cause retrograde ejaculation. As I mentioned in Chapter 1, semen is deposited through the ejaculatory ducts and prostate ducts into the urethra as it runs through the prostate. At the same time, the bladder neck closes and the external sphincter below the prostate closes also. This causes the development of a high-pressure zone within the prostate. The external sphincter then opens and the semen is propelled out of the urethra through the penis by rhythmic contractions of the muscles surrounding the urethra. However, in men who have a bladder neck that does not close properly, such as those men who are on alpha blockers, there is a propensity for the semen to travel in a retrograde fashion back into the bladder rather than out through the urethra. This is not a dangerous situation, but it does result in the presence of a dry orgasm, which is alarming for some men.
5–alpha reductase inhibitors (Table 2) are a fairly new drug class available to physicians. They were first introduced to the US in 1996. There are two drugs that are currently available in the United States: finasteride (Proscar) and dutasteride (Avodart). These work in an entirely different fashion to alpha-blockers.They actually shrink the prostate by blocking the production of 5–alpha reductase. Remember that 5–alpha reductase is that enzyme that degrades testosterone to DHT, the latter being the primary hormone that causes prostate growth. These agents can take between three to six months to effect any significant reduction in prostate size and usually, at best, men have a 30 to 50% reduction in their prostate size. It is also important to understand that 5–alpha reductase inhibitors will reduce the PSA level by approximately 50%, and therefore, it is critical that a man have his PSA level checked before starting one of these drugs. 5–alpha reductase inhibitors are also used for male pattern baldness. In fact, the first commercially available male baldness drug, Propecia, is low-dose finasteride.
| Table 2 • Medications for LUTS |
| Alpha-Blocking Agents |
| Doxazosin (Cardura) |
| Terazosin (Hytrin) |
| Tamsulosin (Flomax) |
| Alfuzosin (Uroxatral) |
| 5–Alpha Reductase Inhibitors |
| Finasteride (Proscar) |
| Dutasteride (Avodart) |
Most urologists tend to reserve the use of 5–alpha reductase inhibitors