What Is Benign Prostatic Hyperplasia

Benign prostatic hyperplasia (BPH) is a common cause of lower urinary tract symptoms in men.^1,11 Benign prostatic hyperplasia is known by other names such as benign prostatic enlargement and bladder outlet obstruction. While BPH describes the histological changes in the prostate gland, benign prostatic enlargement (BPE) refers to an increased size of the prostate gland and bladder outlet obstruction (BOO) relates to urinary obstruction.^1,2 Benign prostatic hyperplasia is not a cancer.

Hyperplasia refers to an increase in the number of cells. Benign prostatic hyperplasia is characterized by the proliferation (increase) of stromal and epithelial cells in the prostate transition zone, which eventually compresses the urethra and obstructs bladder outflow.^3,8 This results in lower urinary tract symptoms such as frequently getting up at night to urinate, a sense of urgency to pass urine, dribbling after passing urine and leaking of urine.⁶ There are about 3 million men in the UK who have BPH-related lower urinary tract symptoms associated with BPH.⁵

Benign prostatic hyperplasia is a major health concern in older men.¹³ The burden worldwide has been increasing in recent years due to population growth and ageing, especially in low-income and middle-income countries.⁴ The true incidence of benign prostatic hyperplasia is underreported because not all men develop symptoms (and thus visit the hospital) while some of those who develop symptoms decide to manage it.^3,13 However, the prevalence is highest in men aged 75–79 years.^4,11 In the UK, the incidence ranges from approximately 50% among men between 50-60 years to 90% for men older than 80 years of age.⁵

Overview

The prostate is part of the male reproductive system. The prostate is located below the bladder and in front of the rectum. The urethra passes through the prostate. In healthy adults, the prostate is the size of a walnut, weighs about 30 grams and has a volume of approximately 20ml.^6,7 The prostate gland can be divided into three glandular zones: the transition zone which is the innermost part and surrounds the urethra; the central zone which surrounds the transition zone; and the peripheral zone which is the outermost and largest part of the prostate gland.^8,9,10 The prostate’s function is during sexual intercourse when it produces a fluid (which contains the prostate-specific antigen [PSA] enzyme) which mixes with the sperm cells (from the testes) and other fluid (from the seminal vesicle and bulbourethral gland) to form the semen.^6,7 The contraction of prostate muscles then expels the semen into the urethra during ejaculation.

Causes of benign prostatic hyperplasia

The cause of benign prostatic hyperplasia is unknown though it is believed changes in androgenic hormonal levels lead to the loss of homeostasis (balance) between proliferation and death of the prostate cells, resulting in uncontrolled cell proliferation.¹¹ Testosterone is produced in the testes and transported to the prostate where it is converted to dihydrotestosterone (DHT) by the 5-alpha-reductase 2 enzyme in the stromal cells of the prostate.^1,12 

Signs and symptoms of benign prostatic hyperplasia

Symptoms can be classified as storage or voiding.^6,13

Storage symptoms include:

• Frequent urge to pass urine, especially at night when one keeps getting up to use the toilet.
• Sudden urge to pass urine immediately.
• Urine incontinence and leakage, that is the unintentional passing of urine.
• Recurrent urine infections.

Voiding symptoms include:

• Weak urine flow.
• Urine hesitancy that is, straining or difficulty starting to pass urine when in the toilet
• A sense of incomplete emptying of the bladder, even after passing urine
• Intermittency, that is, urine flow that is not continuous and involves multiple start-stop when passing urine
• Urine dribbling (post-void dribble) which is an involuntary loss of urine immediately after urinating

Management and treatment for benign prostatic hyperplasia

Treatment of benign prostatic hyperplasia depends on the severity of symptoms and impact on the individual’s quality of life.¹¹

Lifestyle changes include weight loss, drinking less fizzy drinks, alcohol, caffeine and artificial sweeteners as these can irritate the bladder and make urinary symptoms worse; drinking less fluid in the evening and at least 2 hours before going to bed; emptying your bladder before long journeys or before events where toilets are not easily accessible; reviewing medications with your doctor, such as antidepressants or decongestants which might worsen urinary symptoms; eating more fibre (fruit, vegetables and wholegrain cereals) which prevent constipation, and reduce the pressure on the bladder; using absorbent pads inside your underwear to soak up any leaks; and bladder training programme that helps you hold urine longer in the bladder.^1,16

Medical treatment options include alpha-adrenergic receptor antagonists such as tamsulosin and alfuzosin which relax the prostate muscle and make urinating easier; anticholinergics which relax the bladder muscle if it's overactive; 5-alpha reductase inhibitors such as finasteride and dutasteride which shrink the prostate gland if it's enlarged; diuretics which reduce the amount of urine produced during the night if taken during the day; and desmopressin which reduce the amount of urine produced at night.^11,15

Surgical options include:^12,13 

• Transurethral resection of the prostate (TURP) where the central and peripheral zones are removed
• Transurethral incision of the prostate (TUIP) which is recommended for prostate glands less than 30g, Where one or two small cuts are made in the prostate gland to relieve urine obstruction
• Open prostatectomy which is recommended for prostate glands weighing more than 100g
• Transurethral electro-vaporization of the prostate (TUVP)
• Laser prostatectomy
• Transurethral microwave therapy (TUMT) 

Diagnosis

Diagnosis of benign prostatic hyperplasia combines medical history, physical examination, and laboratory tests.^1,11,13,14

When discussing your medical history with a doctor, the doctor may decide to use a questionnaire called the International Prostate Symptom Score (IPSS) to objectively evaluate the severity of your symptoms. A score of 0 to 7 suggests symptoms are mild; a score of 8 to 19 suggests moderate symptoms and a score of 20 to 35 suggests severe symptoms.

During a physical examination, the doctor will palpate the abdominal area for any signs of a full bladder or residual urine. The testis and external genitalia will also be examined. Next, a digital rectal exam is done to assess the size, shape, symmetry, quality, nodularity, and consistency of the prostate.

Finally, prostate-specific antigen (PSA) tests and urinalysis are done. PSA is a biomarker for prostate cancer but can be used to diagnose BPH. The doctor will provide full information on PSA before the test is done. Optional laboratory tests (depending on the doctor’s findings from all of the above) include urine culture, blood glucose, postvoid residual measurement, urodynamic pressure flow study, cystoscopy, and transrectal ultrasound (TRUS).

Risk factors

Common risk factors that provide the background for BPH are race (black), positive family history of prostate disease, smoking, age (above 50 years), obesity, metabolic syndrome, sedentary lifestyle, diabetes, and excessive consumption of meat.^11,12

Complications

Complications of BPH include acute urine retention, chronic urine retention, urinary tract infection (due to incomplete emptying), haematuria (blood in urine), bladder calculi (bladder stones that form due to incomplete emptying), and obstructive uropathy (rare but most severe complication).^1,11,12,13

FAQs

How can I prevent benign prostatic hyperplasia?

Prevention of benign prostatic hyperplasia is through lifestyle changes such as regular exercise and weight loss; drinking less alcohol; and eating more fibre.

How common is benign prostatic hyperplasia?

The true incidence of benign prostatic hyperplasia is underreported because not all men develop symptoms while some of those who develop symptoms decide to manage it. However, the prevalence is highest in men aged 75–79 years. In the UK, the incidence ranges from approximately 50% among men between 50-60 years, and 90% in men older than 80 years of age.

When should I see a doctor?

See your doctor if you have any of these symptoms:¹⁶

• Frequent urge to urinate
• Need to get up many times during the night to urinate
• Blood in urine or semen
• Pain or burning urination
• Painful ejaculation
• Frequent pain or stiffness in the lower back, hips, pelvic or rectal area, or upper thighs
• Dribbling of urine

Summary

Benign prostatic hyperplasia (BPH) is a common cause of lower urinary tract symptoms in men. It is characterized by the proliferation (increase) of stromal and epithelial cells in the prostate transition zone, which compresses the urethra and obstructs bladder outflow, eventually resulting in lower urinary tract symptoms such as frequently getting up at night to urinate, a sense of urgency to pass urine, dribbling after passing urine, and leaking of urine. The true incidence of benign prostatic hyperplasia is underreported because not all men develop symptoms (and thus visit the hospital) while some of those who develop symptoms decide to manage it. The prevalence is highest in men aged 75–79 years. Diagnosis is through a combination of medical history, physical examinations, and laboratory tests. Treatment options include changes in lifestyle, medical treatments, and surgical procedures.