BENIGN PROSTATIC HYPERPLASIA


I. Epidemiology and natural history

  1. Prevalence of BPH is 20% at 40yo but increases with age
  2. In a study in 500 pts with symptomatic BPH who chose watchful waiting and were initially classified as having mild, moderate, or severe BPH according to a sx questionnaire, at 4y f/u, 83% in mild group and 59% in moderate group still had mild or moderated sx; the remainder had progressed to severe or undergone surgery. Only 20% of pts with severe sx at baseline regressed to less sx. (J. Urol 157:10, 1997-JW)

II. Clinical features

  1. Lower urinary tract symptoms ("LUTS") [correlate poorly with degree of BPH]:
    1. Urinary hesitancy
    2. Sensation of incomplete emptying
    3. Urinary frequency
    4. Urinary urgency
    5. Nocturia
    6. Slowing of stream
  2. Other potential causes of LUTS:
    1. Medications
    2. Sequelae of surgery
    3. Prostaic infection
    4. Prostatic malignancy
    5. Detrusor dyssynergia
    6. Urethral stricture
    7. Central neurologic disease
  3. Standardized assessment of LUTS: the AUA symtpoms index (www.ucurology.net/documents/aua_symptom_form.pdf)
  4. Rarely-Acute urinary retention (risk depends on prostate size; correlates with serum PSA-is 5% with LUTS + PSA > 3.2 ng/dL, and < 2% for PSA < 1.3 ng/dL)

III. Management-treatment indicated if post-void residual is high or symptoms are bothersome

  1. Surgery
    1. Transurethral resection of the prostate ("TURP") --0.2% mortality, 5-10% morbidity; fails to resolve sx in 20%
    2. Laser therapy vs. TURP--Sympomatic outcomes were better with TURP (not stat. sig.) with no diff. in major complications in one randomized trial of 340 pts with BPH (J. Urol. 164:65, 2000--JW)
    3. Hot water balloon thermoablation (done as an outpatient under topical anesthesia)
    4. Other techniques: holmium laser enucleation of the prostate (HoLEP), microwave therapy (TUMP), transurethral incision of the prostate (TUIP)
  1. Medication
    1. Alpha-1 Adrenergic Blockers
    2. 5-alpha-reductase inhibitors
      1. Inhibit the conversion of testosterone to dihydro-testosterone
      2. Can take up to 3 months to have significant symptomatic effect
      3. Can cause decrease in volume of ejaculate, erectile dysfunction, decreased libido, and gynecomastia
      4. AUA symptom scores do not predict response, but a prostate volume on ultrasound of > 30mL does (as does a serum PSA level of > 1.4 ng/dL)
      5. Finasteride (Proscar) 5mg PO QD
        1. Finasteride ass'd with lower (RR 0.43) risk of acute urinary retention and lower (RR 0.5) risk of need for surgery c/w placebo in a 4y trial in 3040 men with mod-severe BPH sx and enlarged prostate (NEJM 338:557, 1998--UW Pharm. Letter)
      6. Dutasteride (Avodart) 0.5mg PO QD
        1. In a study in 6,729 men 50-75yo with at hight risk for prostate cancer treated with dutasteride 0.5mg QD vs. placebo x 4y, dutasteride recipients had sig. higher incidence of heart failure (0.7% vs. 0.4%).  (NEJM 362:1192, 2010-abst) (see section on Prostate Cancer for details on effect on prostate Ca incidence) 
    3. Saw Palmetto (click link for info)
    4. Comparisons among different meds
      1. 1229 men with symptomatic BPH randomized to terazosin 10mg QD vs. finasteride 5mg QD vs. both vs. placebo x 1y and measured sx scores. Terazosin was sig. better than placebo and finasteride; finasteride was no better than placebo; combination tx no better than terazosin alone. Similar results with urine flow rates.
      2. 3047 men with moderate-to-severe BPH randomized to doxazosin, finasteride, both, or double-placebo.  Over mean 4y f/u, incidence of a composite clinical endpoint was sig. lower with combination therapy (5%) than with either monotherapy (10%).  (NEJM 349:2387, 2003--JW)
  1. (Sources include Core Content Review of Family Medicine, 2012)