Urology/Re: Overactive bladder and BPH
I have a question about the overactive bladder and outflow obstruction due to the BPH. I read anticholinergic drugs are contradicted with the relief of the outflow obstruction and Alpha Blockers. Is it common the BPH patient has the overactive bladder? What is the effective treatment to the patient who has both of overactive bladder and BPH? Thank you for your answer.
Ray, overactive bladder is a symptom complex that can be due to many causes. By far the most common in men is BPH. This is due to the enlarged prostate growing into the urethra as well as under the very sensitive bladder floor (trigone area) producing these irritative symptoms. Most men with BPH have some degree of overactive bladder. Other causes for overactive bladder include bladder stones, infection, excessive fluid consumption, excessive consumption of diuretic substances (coffee, tea, beer, etc.), anxiety, although in many cases a specific etiology cannot be determined. To follow is a "macro" I have written on BPH that will provide additional information. In addition, I will comment on why anticholinergics are contraindicated.
Benign enlargement of the prostate gland (benign prostatic hyperplasia or BPH) occurs to varying degrees in all men as they age. The prostate surrounds the urinary canal (urethra) just after its connection to the urinary bladder. Inward growth of the prostate either into the bladder neck (opening) or into the urethra itself can cause difficulty with urinating. The prostate is checked by digital examination through the rectum. This gives the doctor an idea as to the size and benignity of the gland. However, it does not always correlate to symptoms as a small gland may have significant inward growth and a large glands enlargement may be entirely peripheral.
The ability to urinate involves the urinary bladder muscle actually becoming stronger as it works against increasing resistance from the enlarged prostate. This delicate balance can be upset by any factor that decreases the bladder muscles ability to contract with sufficient force to open the prostate (such as medications, anesthesia, too much alcohol, ignoring the desire to urinate, etc.) or those factors that might cause the prostate to suddenly swell (ie acute prostatitis, sitting for extended periods of time, biking, horseback riding, etc.). Anticholinergics, although helpful in relieving irritating urinary symptoms in many causes of overactive bladder, are contraindicated with BPH because relaxing the bladder muscle may not allow it to generate sufficient force to open the prostatic urethra and empty the bladder. As a result, in men with BPH, this could result in urinary retention.
The typical symptoms that occur include diurnal frequency (daytime), nocturia (night-time frequency), urgency, hesitancy, slow stream and dribbling after voiding. This complex of symptoms is termed “prostatism”. If the obstruction to flow progressively worsens, the bladder eventually may not be able to empty completely. This leads to the accumulation of “residual urine” which may predispose to urinary infections and kidney damage from back pressure.
However, relatively asymptomatic men with BPH do NOT necessarily require therapy. Treatment is indicated to relieve symptoms and prevent complications. In many cases medications can be used. Alpha - blockers (ie Hytrin, Cardura, Flomax, Uroxatral etc.) work by relaxing the bladder neck and urethra so the pressure generated by a bladder contraction has less resistance to work against. Natural herbal products such a saw palmetto and pygeum often provide symptomatic relief but the exact mechanism of action has not yet been defined. The prescription drugs Proscar and Avodart actually shrink the prostate. They work best in the larger glands and improvement may not be noted for up to 6 months. In cases refractory to medication, interventional measures are indicated. The “gold standard” for treatment is the time honored transurethral resection (TUR) of the prostate. For huge glands, open surgery may be necessary. In the past decade a number of other less invasive interventional therapies have been developed to reduce the obstructing prostate tissue utilizing various forms of energy. These include laser prostatectomy, microwave (TUMP or transurethral microwave of the prostate), and radiofrequency (TUNA or transurethral needle ablation of the prostate). TUMP is actually a minimally invasive, out-patient treatment that can be tried initially if the patient's gland size is appropriate.
Here is an explanation of a TUR of the prostate gland. The prostate gland can be thought of as being composed basically of three parts which from inside to out are: the prostatic portion of the urethra (urinary canal), the prostatic glandular tissue causing the obstruction (adenoma) and the compressed capsule of the prostate. In a TUR, the prostatic urethra and adenoma are removed leaving only the capsule. This surgery can be likened to coring out an apple from the inside leaving only the skin. The prostate is resected into many tissue slivers which wash into the bladder and then are removed at the end of the operation by suction. This leaves a raw bed, which, over a period of 6-8 weeks, regenerates a new urethra! At the termination of the procedure, one can look from the far end of the prostate into the bladder without residual obstruction. A catheter is left in for a few days to drain the bladder and to initiate the healing process. Good luck!