UPDATE - Issue 03 - June 1999
Prostate Enlargement
We review a condition likely to affect almost all men
Benign enlargement (hyperplasia) of the prostate, known as BPH usually begins in the fourth decade of life. Over 50% of men over 50 have it and 75% of those over 80. So if one lives long enough you are likely to have the condition. The good news is that not all men with BPH have symptoms. Community studies show that 28% of men over 40 and 43% over 60 exhibit symptoms.
The Causes
The exact cause of BPH remains unknown but advancing age and androgens are important factors. The development of BPH requires testosterone. Many other factors including genetic variation contribute to its development. Bladder outflow obstruction, which gives rise to the main symptoms, can develop from either static obstruction - that is the increasing bulk of the gland creating pressure on the bladder and urethra - or dynamic obstruction due to an increase in tension of the smooth muscle in the prostate. Once the bladder fails to generate sufficient power to empty itself, residual urine remains after voiding which reduces the effective bladder capacity and predisposes to other conditions such as urinary infections and bladder stone formation.
The Symptoms
BPH produces two main groups of symptoms, obstructive and irritative. Obstructive symptoms include a reduced urinary stream, hesitancy, intermittency and terminal dribbling. Irritative symptoms, which patients find the more distressing, include frequency, urgency and urge incontinence notably at night.
When a patient goes to his doctor with the symptoms of BPH, he is likely to be asked a number of questions about the precise symptoms and the resulting quality of life. From these a standardised prostate symptom score is derived with results ranging from mild through moderate to severe. Other tests may then follow, flow rate measurements, ultrasound examination, digital rectal examination, biopsy and blood tests. The last two are necessary to rule out a diagnosis of prostatic cancer.
Current Treatments
Quite a high proportion of patients(40%) require no treatment for the time being, just routine check ups. Of these, over half will be no worse five years later, which illustrates how slow to develop the condition often is. About 50% of patients will require some form of medical treatment and 10% require surgery.
The drug therapies which are prescribed have been developed either to attack the increased tension in the prostatic smooth muscle (selective alpha blocker drugs) or to reduce the size of the prostate gland (5 alpha-reductase inhibitors). Selective alpha blocker drugs are usually tried first for patients with mild to moderate symptoms. Adverse side effects of tiredness, stuffy nose and postural hypotension are unfortunately quite common.
The 5 alpha-reductase inhibitors take at least six months to become effective, so it is important not to give up on the treatment. The adverse effects include loss of interest in sex, delayed ejaculation and tiredness. In patients with severe symptoms and those who have not responded to drug therapy after a few months, surgery is indicated. The 'gold standard' remains transurethral prostatectomy. Unfortunately, this procedure is associated with an 8% to 10% risk of complications and a significant proportion of patients (as many as 20%) are likely to be dissatisfied with the results.
New Treatments
Several new, much less invasive, treatments - electrovaporisation and laser enucleation - have been developed in recent years in response to the high risks associated with the normal operation. These endeavour to achieve the same as the conventional operation but with reduced risk of bleeding and a shorter hospital stay. As with all new treatments the short term results are good but the long term results have not yet been established. The Department of Health is currently funding a systematic review at the University of Newcastle of research into minimally invasive therapies for BPH. These minimally invasive treatments are available at some but not all NHS hospitals.