What is the most common cause of urinary obstruction in men over 60?

Benign Prostatic Hyperplasia is the Most Common Cause of Urinary Obstruction in Men Over 60

Benign prostatic hyperplasia (BPH) is definitively the most common cause of urinary obstruction in men over the age of 60, with prevalence reaching 60% by age 60 and 80% by age 80. 1

Epidemiology and Prevalence

• BPH is nearly ubiquitous in aging males, with increases starting at age 40-45 years, reaching 60% by age 60, and 80% by age 80 1
• The prevalence of moderate-to-severe lower urinary tract symptoms (LUTS) rises to nearly 50% by age 80 1
• Acute urinary retention increases from 6.8 episodes per 1,000 patient years in the overall population to 34.7 episodes in men aged 70 and older 1
• Approximately 90% of men between 45 and 80 years of age suffer some type of LUTS related to BPH 1

Pathophysiology of Urinary Obstruction in BPH

• BPH contributes to urinary obstruction through two primary mechanisms:
  • Static component: direct bladder outlet obstruction from enlarged prostatic tissue
  • Dynamic component: increased smooth muscle tone and resistance within the enlarged gland 1
• BPH develops due to an imbalance between growth and apoptosis (cellular death) in favor of growth, causing an increase in cellular mass 1
• The T/DHT-androgen receptor complex within prostatic cells initiates transcription of DNA and translation, causing normal development, growth, and hyperplasia of the prostate 1

Clinical Manifestations of BPH-Related Obstruction

• BPH-related urinary obstruction typically presents with:
  • Storage symptoms: urgency, frequency, nocturia
  • Voiding symptoms: weak stream, hesitancy, intermittency, straining, and sensation of incomplete emptying 1, 2
• LUTS may be due to structural or functional abnormalities in one or more parts of the lower urinary tract which comprises the bladder, bladder neck, prostate, distal sphincter mechanism and urethra 3

Complications of Untreated BPH

• Acute urinary retention (AUR) is a significant complication, with risk increasing with age 1
• In the MTOPS study, the risk of developing acute urinary retention was reduced by 67% in patients treated with finasteride compared to placebo (0.8% for finasteride and 2.4% for placebo) 4
• BPH can lead to bladder outlet obstruction (BOO) which can lead to UTIs in men 5
• Recurrent or persistent UTI in men with BPH is an indication for surgical treatment 5

Diagnostic Approach

• Initial evaluation should include:
  • Medical history
  • Physical examination (including digital rectal examination)
  • International Prostate Symptom Score (IPSS)
  • Urinalysis 1
• Additional evaluations may include post-void residual (PVR) measurement and uroflowmetry 1
• The frequency volume chart is recommended when nocturia is a bothersome symptom to exclude nocturnal polyuria 3

Treatment Options

• Alpha-adrenergic antagonists (alpha blockers) are first-line therapy for most men with moderate symptoms 1
• 5-alpha reductase inhibitors (5ARIs) are effective for men with larger prostates (>30cc) 1
• Combination therapy with alpha blockers and 5ARIs has shown greater efficacy than either agent alone 4
• Transurethral resection of the prostate (TURP) remains the gold standard surgical approach for BPH 1
• Treatment should be holistic, and may include conservative measures, lifestyle interventions and behavioral modifications as well as medication and surgery 3

Differential Diagnosis of Urinary Obstruction in Older Men

• While BPH is the most common cause, other potential causes include:
  • Urethral stricture (another form of bladder outlet obstruction) 3
  • Chronic UTIs (can cause symptoms that mimic BPH but are not a primary cause of obstruction) 5
  • Glomerulonephritis (affects kidney function but is not a direct cause of urinary obstruction) 6
  • Kidney stones (can cause obstruction but are less common than BPH in men over 60) 6