What are the treatment options for overactive bladder (OAB) and benign prostatic hyperplasia (BPH), and how is BPH diagnosed?

Diagnosis and Treatment of Overactive Bladder and Benign Prostatic Hyperplasia

Diagnosis of BPH

The diagnosis of BPH requires a comprehensive medical history focusing on urinary symptoms, physical examination including digital rectal examination to assess prostate size, and urinalysis to exclude other conditions. 1

Key Diagnostic Steps for BPH:

• Obtain a detailed medical history focusing on lower urinary tract symptoms (LUTS), including both voiding symptoms (weak stream, hesitancy, intermittency) and storage symptoms (urgency, frequency, nocturia) 1
• Perform a physical examination with digital rectal examination to assess prostate size, shape, and consistency 1
• Conduct urinalysis to exclude microhematuria and infection 1
• Measure post-void residual (PVR) volume in patients with risk factors such as emptying symptoms, history of retention, neurologic disorders, or prior prostate surgery 2
• Consider symptom questionnaires like the International Prostate Symptom Score (IPSS) to quantify symptom severity 3, 4

Treatment for Overactive Bladder (OAB)

First-Line Treatment: Behavioral Therapies

• Bladder training with timed voiding and gradual extension of voiding intervals should be offered to all OAB patients due to excellent safety profile 5, 6
• Pelvic floor muscle training to improve urge suppression techniques 5, 6
• Fluid management, including optimizing timing and volume of fluid intake (1.5-2 liters per day) 2, 6
• Dietary modifications to reduce bladder irritants (caffeine, alcohol, carbonated beverages, artificial sweeteners) 2, 6
• Weight loss for obese patients, targeting 8% weight loss to reduce urgency incontinence episodes 5, 6

Second-Line Treatment: Pharmacotherapy

• Beta-3 adrenergic agonists (e.g., mirabegron) are preferred over antimuscarinics due to their lower cognitive risk 5, 2
• Antimuscarinic medications (darifenacin, fesoterodine, oxybutynin, solifenacin, tolterodine, trospium) are effective alternatives but should be used with caution in patients with cognitive impairment risk 5, 2

Treatment for BPH with OAB

For patients with BPH and bothersome OAB symptoms, clinicians should offer combination therapy with an alpha blocker and either an antimuscarinic medication or a beta-3 agonist for optimal symptom control. 1

Pharmacologic Options:

• Alpha blockers (e.g., tamsulosin, doxazosin) to relieve bladder outlet obstruction 1, 7
• 5-alpha reductase inhibitors (finasteride, dutasteride) for men with enlarged prostates to reduce prostate volume 3, 4
• Combination therapy with alpha blockers and antimuscarinics or beta-3 agonists for patients with persistent storage symptoms 1, 8

Evidence for Combination Therapy:

• Studies show that combination therapy with alpha blockers and antimuscarinics significantly improves storage symptoms compared to alpha blockers alone 8, 9
• Combination therapy has demonstrated improvements in quality of life and patient satisfaction rates 9, 10
• Earlier initiation of combination therapy provides faster relief of storage symptoms 10

Special Considerations and Precautions

• Monitor post-void residual volume when using antimuscarinics in BPH patients, as they may slightly increase PVR but rarely cause urinary retention in appropriately selected patients 1, 9
• Use antimuscarinics with caution in patients with narrow-angle glaucoma, impaired gastric emptying, or history of urinary retention 5
• Consider PVR greater than 250-300mL as a relative contraindication for antimuscarinic use 5
• Most patients experience significant symptom reduction rather than complete resolution with treatment 5, 2
• Patients with BPH may experience de novo or worsening OAB symptoms after surgical interventions for BPH 1

Treatment Algorithm for BPH with OAB

1. Initial evaluation: Medical history, physical examination, urinalysis, and PVR measurement 1
2. First-line: Behavioral therapies including bladder training, fluid management, and dietary modifications 2, 6
3. For persistent symptoms: Initiate combination therapy with alpha blocker plus antimuscarinic or beta-3 agonist 1, 8
4. For patients with enlarged prostates (>40cc): Consider adding 5-alpha reductase inhibitor 3, 4
5. For refractory symptoms: Consider referral for minimally invasive or surgical interventions 1