Benign Prostatic Hyperplasia (BPH)

By Rajveer S. Purohit, MD, MPH

Background
Benign prostatic hyperplasia or BPH is a common condition that increasingly affects men as they age. The National Institutes of Health has suggested that up to 75% of men over the age 70 will be affected by this condition. Typically, patients present with gradual worsening of urinary symptoms but occasionally have an acute and dramatic change in their condition such as a complete inability to urinate (urinary retention) or severe pain with urination caused by an infection. BPH is not cancer and will not become prostate cancer although occasionally prostate cancer can also cause urinary symptoms.

Anatomy
The prostate is a gland present only in men. It is involved in reproduction and sits deep in the pelvis below the bladder. The bladder stores urine and empties itself through a channel (urethra) that runs through the prostate gland and downstream through the penis and out (hopefully) into the toilet.

As men age, the prostate gland will grow and begin to block the channel the urine flows through. It is like a tunnel whose walls gradually begin to thicken and grow narrowing the roadway and causing traffic to slow down. However, it is not only the volume of tissue that causes obstruction but there is also increased “tension” within the prostate which “squeezes” the channel and causes urinary symptoms. Because of this, though larger prostate glands typically cause obstruction, prostate size itself does not always predict the severity of urinary symptoms.

Symptoms
Symptoms of BPH typically include both irritative and obstructive urinary symptoms. Irritative symptoms include urinary frequency, urgency and waking up to urinate at night.  Obstructive symptoms include a weak stream, urinary hesitancy (which is an initial delay in ability to void) and double voiding (which is urinating twice to empty more completely). Nighttime urination, called nocturia, can be caused by an enlarged prostate gland but frequently has other causes. In addition to bothersome symptoms, BPH can also cause other acute problems such as urinary tract infections, recurrent episodes of bleeding in the urine and inability to urinate. Long-term problems include structural changes in the bladder muscle that will cause it to no longer function normally and permanent kidney damage.  Occasionally, men will present with urinary incontinence secondary to BPH if they have a full bladder or urinary retention, that can no longer hold any further urine and starts to leak, a condition called overflow incontinence.

Diagnosis
The diagnosis of BPH is made by a doctor who should take a careful medical history focusing on urinary symptoms such as urgency, frequency, nocturia, double voiding, urinary hesitancy and a weak urinary stream. Additional clues suggesting a diagnosis of BPH include episodes of urinary retention or urinary tract infections, and hydronephrosis or a swelling in the tube that connects the kidney to the bladder, seen on radiolologic imaging. The examination should be a full physical exam including a digital rectal exam to evaluate the prostate.

Laboratory analyses that are useful include tests for kidney function (creatinine) and a PSA (prostate specific antigen) that has been commonly used for screening for prostate cancer but is also a useful surrogate for prostatic size. In addition to this, I routinely assess the urinary flow rate using a machine that measures the speed of urination. A slow speed suggests either an obstructed urinary flow or a weak bladder muscle - both of which can be caused by BPH. An ultrasound done after urination can determine the presence of any residual urine and suggest the degree of obstruction. In patients who have evidence of symptomatic BPH I routinely use a 24 hour voiding diary to clarify and quantify urinary symptoms.

Other tests that can help determine the severity of BPH include an ultrasound of the prostate to determine its size and an ultrasound of the kidneys to rule out evidence that urine has backed up the ureters from the bladder into the kidneys (hydronephrosis). In some patients, a cystoscopy, a anesthesia and a video-urodynamics, which assess bladder and prostate function and determines the extent of prostate obstruction, can be very helpful.

Treatment
Once the diagnosis of BPH has been made, patients and doctors have a number of options for treatment. Not all patients who have BPH need to be treated. If symptoms are not bothersome and patients do not have a history of recurrent infections, bleeding, or evidence of bladder or kidney damage, in consultation with their urologist, patients may safely choose to just closely monitor their condition. This is called "watchful waiting" or "observation."

For patients who choose to be treated, options include medications or a surgical procedure. Broadly speaking, there are two classes of medications available for treatment of BPH: alpha-blockers and 5-alpha reductase inhibitors. Alpha-blockers, which affect the smooth muscle in the prostate, tend to decrease its “tension” and include medications such as tamsulosin (Flowmax®), alfuzosin (Uroxatral®), silodosin (Rapaflo®), terazosin (Hytrin) and doxazosin (Curdura). Side effects are not common but include lightheadedness, headaches and decreased ejaculated volume. The 5-alpha reductase inhibitors work by decreasing the effects of testosterone on the prostate and include finasteride (Proscar®) and dutasteride (Avodart®). Unlike alpha-blockers, they work by decreasing the size of the prostate gland. Side effects include decreased ejaculatory volume, erectile dysfunction and decreased libido. Some patients may find benefit by taking a medication from both classes.

Medications usually provide some benefit for most patients but in my experience, the most dramatic improvement in symptoms usually occurs from surgical treatment of BPH. There are many variations of procedures that can be done and these range from minimally invasive, office-based treatments using heat or some other form of energy to reduce the size of the gland or increase the "channel" in the prostate through which urine passes during urination. The most common of these procedures is microwave thermotherapy. These are typically done under light sedation and local anesthesia and are well tolerated by patients. The “gold” standard has traditionally been considered a transurethral resection of the prostate (TURP). In this procedure, a scope is placed into the urethra and the prostate is “cored” out from the inside-out, leaving a rim of outer prostate behind and a large cavity where once obstructing tissue existed. The procedure has high success rates in appropriately diagnosed and selected patients, hence the term "gold" standard. Common side effects include blood in the urine and longer lasting decreased quantity of ejaculate. Patients also experience longer hospital stays and some may need to have a Foley catheter placed after the procedure. An alternative I use is the GreenLight® laser photoselective vaporization of the prostate (PVP) which is an outpatient procedure that has equal efficacy and a substantially lower chance of bleeding and other side effects. There are many other variations of BPH treatments, and it is important that patients understand the different advantages and side effects of each and use a doctor familiar, experienced and well-trained in the procedure.

Summary
In summary, BPH is a disorder that becomes more common in men as they age and can be diagnosed based on a thorough physical exam, history and diagnostic tests. Symptoms typically include urinary frequency, urgency, slow urinary stream and nighttime voiding. If left untreated, patients can develop urinary infections, bladder damage, retention and even kidney failure. Quality of life can be impaired. However, the majority of men can be treated with relief of their symptoms with medications or surgery, with minimal adverse effects.

About the author:
Rajveer S. Purohit, MD, MPH, is a clinical assistant professor of urology at the Weill Medical College of Cornell University