Benign prostatic hyperplasia (BPH), commonly referred to as an enlarged prostate, is the most common urological condition affecting men over the age of 50. By the age of 60, approximately half of all men have BPH; by 80, this rises to 80-90%. In Singapore, where the male population is ageing, BPH represents one of the most prevalent and most undertreated conditions in men's health.
BPH is not cancer and it is not a precursor to cancer. But its symptoms, frequent urination, weak stream, waking at night to urinate, difficulty starting and stopping, significantly affects sleep, concentration, daily activities, and quality of life. And in a subset of men, untreated BPH may lead to serious complications including acute urinary retention, bladder damage, and kidney impairment.
What is the Prostate and What is Benign Prostate Hyperplasia (BPH)?
The prostate is a walnut-sized gland located directly below the bladder in men, surrounding the urethra, the tube through which urine passes from the bladder out of the body. The prostate's primary function is to produce seminal fluid that nourishes and transports sperm.
The prostate goes through two main growth phases in a man's life: rapid growth during puberty, and a second, slower phase of growth that begins around age 25 and continues throughout life. For most men, this gradual enlargement has no consequences in their 30s and 40s. But as the prostate grows, it can press on and narrow the urethra, making it progressively harder for urine to flow freely. This is BPH.
The term 'benign' is important -- it means the enlargement is not caused by cancer and carries no direct cancer risk. BPH is driven by hormonal changes, particularly the accumulation of dihydrotestosterone (DHT) within prostate tissue, which stimulates continued cell growth. The smooth muscle component of the prostate also contributes by contracting and further narrowing the urethra.
Symptoms: Understanding Lower Urinary Tract Symptoms (LUTS)
BPH causes lower urinary tract symptoms (LUTS) -- a group of urinary symptoms that can be categorised by when in the urination cycle they occur. Recognising which type of symptoms predominate helps guide treatment selection.
Storage (Irritative) LUTS
- Urgency: A sudden, compelling urge to urinate that is difficult to defer.
- Frequency: Passing urine more often than every 2 hours during the day.
- Nocturia: Waking one or more times per night to void.
- Urgency incontinence: Leaking urine before reaching the toilet.
These symptoms arise from the bladder responding to obstruction with increased contractility and reduced capacity.
Voiding (Obstructive)LUTS
- Hesitancy: Difficulty initiating urination despite a full bladder.
- Poor stream: Reduced force and calibre of urine flow.
- Straining: Needing to push or strain to initiate or maintain flow.
- Intermittency: Urine flow that starts and stops.
These symptoms arise directly from the mechanical obstruction of the urethra by the enlarged prostate.
Post-Micturition Symptoms
- Incomplete emptying: A persistent sensation that the bladder has not emptied fully.
- Post-micturition dribble: Involuntary leakage of urine immediately after finishing voiding, caused by urine pooling in the bulbar urethra.
These symptoms are particularly common in BPH and represent a combination of obstructive and residual urine effects.
When Symptoms Signal Complications
Haematuria (blood in the urine), recurrent urinary tract infections, bladder stones, or significantly elevated post-void residual urine on scan suggest that BPH is causing complications and warrants prompt urological assessment and likely active treatment rather than continued watchful waiting.
Causes and Risk Factors
What causes the prostate to enlarge?
BPH results from a combination of:
- Hormonal changes with ageing -- declining testosterone and rising oestrogen levels alter the balance of growth signals in prostate tissue
- Dihydrotestosterone (DHT) accumulation -- DHT, derived from testosterone by the enzyme 5-alpha reductase, accumulates in the prostate and stimulates cell proliferation
- Smooth muscle hypertrophy -- the smooth muscle component of the prostate enlarges and contracts, contributing to urethral obstruction alongside the glandular tissue
Risk factors
- Age: The most significant risk factor. BPH is rare under 40 and nearly universal by 80
- Family history: Men with a first-degree relative with BPH are significantly more likely to develop it themselves
- Metabolic syndrome: Diabetes, hypertension, obesity, and dyslipidaemia are associated with an increased risk and faster progression of BPH
- Sedentary lifestyle: Physical inactivity is independently associated with BPH risk and symptom severity
- Diet: High red meat consumption, low vegetable intake, and high alcohol consumption are associated with increased BPH risk
- Testosterone therapy: Exogenous testosterone may exacerbate BPH symptoms in some men by increasing DHT levels
Complications of Untreated BPH
Many men manage BPH symptoms indefinitely without seeking treatment. While mild symptoms can be monitored safely, progressive obstruction can cause complications that are preventable with timely treatment:
- Acute urinary retention (AUR): Sudden, complete inability to pass urine. A urological emergency requiring immediate catheterisation. The risk of AUR roughly doubles with each decade of age above 60 and increases with prostate size and symptom severity. Risk is not always predicted by prior symptom pattern -- AUR can occur in men with only moderate symptoms.
- Chronic urinary retention: Gradual, painless accumulation of residual urine in the bladder, often without the patient's awareness. May lead to overflow incontinence. Detected on post-void residual ultrasound measurement.
- Urinary tract infections: Incomplete bladder emptying creates a reservoir of stagnant urine that promotes bacterial growth. Recurrent UTIs in a man over 50 warrant urological assessment.
- Bladder stones: Calculi (stones) form in the bladder when stagnant urine concentrates over time. Cause haematuria, pain, and recurrent infection.
- Bladder dysfunction: Chronic over-work of the detrusor muscle from increased voiding pressure eventually leads to muscle hypertrophy and then failure; the bladder may lose its ability to contract effectively even after the obstruction is relieved.
- Hydronephrosis and renal impairment: In severe, longstanding cases, back-pressure from chronic urinary retention travels to the kidneys, causing swelling (hydronephrosis) and, ultimately, renal function decline.
Lifestyle and Self-Management Tips
Lifestyle changes are an important adjunct to medical or surgical treatment -- and for men with mild symptoms, they may be sufficient to maintain quality of life without medication:
- Spread fluid intake evenly throughout the day; reduce intake after 6pm to minimise nocturia
- Limit caffeine (coffee, tea, energy drinks) and alcohol, which increase urgency and frequency
- Practise double voiding -- after urinating, wait a moment and try again to more completely empty the bladder
- Avoid prolonged sitting; standing and gentle movement can relieve bladder pressure
- Maintain a healthy weight -- central obesity is associated with more severe LUTS
- Exercise regularly -- studies consistently show that active men have lower rates of BPH progression
- Review all medications with your urologist -- antihistamines, some antidepressants, decongestants, and anticholinergic drugs can worsen urinary symptoms
- A bladder diary (recording time and volume of each void for 3 days) provides your urologist with objective data beyond what symptoms alone can convey -- ask your clinic for a template
How is BPH Diagnosed?
BPH diagnosis is clinical -- based on symptoms, examination, and targeted investigations. The purpose of the diagnostic workup is threefold: to confirm BPH as the cause of symptoms, to exclude prostate cancer and other diagnoses, and to assess the severity of obstruction and its impact on the bladder and kidneys.
- IPSS Questionnaire: Standardised 7-question symptom severity score. Completed before or at consultation to quantify symptoms and guide treatment decisions. Repeated at follow-up to assess treatment response.
- Digital Rectal Examination: Physical examination of the prostate through the rectum. Assesses prostate size, consistency, and symmetry. An irregular or hard nodule on DRE raises concern for prostate cancer. Quick, well-tolerated, and essential at every prostate assessment
- PSA Blood Test: Prostate-specific antigen is elevated in BPH (proportional to prostate size) and in prostate cancer. Used to assess cancer risk alongside DRE, and to estimate prostate volume (PSA density). Elevated PSA warrants further investigation even when BPH is the primary diagnosis.
- Urinalysis and Urine Culture: Excludes urinary tract infection and haematuria as contributors to symptoms. Haematuria requires separate investigation even if BPH is confirmed. Urine culture guides antibiotic treatment if infection is present.
- Cytoscopy: A flexible camera passed through the urethra to directly visualise the urethra, prostate, and bladder interior. Identifies bladder stones, tumours, urethral strictures, and the degree of prostatic obstruction. Performed under local anaesthetic as an outpatient procedure.
