Differentiating Overactive Bladder from Benign Prostatic Hyperplasia

Clinical Presentation

The American Urological Association suggests that overactive bladder is characterized by sudden, compelling urgency that is difficult to defer as the hallmark symptom, while benign prostatic hyperplasia primarily presents with voiding symptoms alongside storage symptoms, and requires digital rectal examination showing prostatic enlargement 1, 2, 3
Urgency is the defining feature of overactive bladder - a sudden, compelling desire to void that is difficult to defer, which must be present for diagnosis, according to the International Continence Society 1, 2
Storage symptoms, such as frequency and nocturia, predominate in overactive bladder, with symptoms occurring in the absence of prostatic enlargement on examination 1, 2
Benign prostatic hyperplasia presents with a mixed symptom pattern, including both voiding and storage components, with voiding symptoms being prominent, as stated by the European Association of Urology 3, 4

The American Urological Association recommends documenting the presence and severity of urgency, as well as assessing voiding pattern, to differentiate between overactive bladder and benign prostatic hyperplasia 1, 2, 3
Digital rectal examination is mandatory to assess prostate size, consistency, and exclude nodules, according to the European Association of Urology 3, 4
The International Prostate Symptom Score (IPSS) should be administered to quantify symptom severity and distinguish voiding from storage symptoms, as recommended by the American Urological Association 3, 4
A 3-day bladder diary should be obtained to differentiate small-volume frequent voids from normal/large-volume voids, as suggested by the International Continence Society 1, 4

Elevated post-void residual (>100 mL) indicates bladder outlet obstruction from benign prostatic hyperplasia, while normal post-void residual suggests overactive bladder, according to the European Association of Urology 4, 5
Maximum flow rate <10 mL/second indicates significant obstruction from benign prostatic hyperplasia, as stated by the American Urological Association 5

Urinalysis should be performed to exclude infection and hematuria in both conditions, as recommended by the American Urological Association 1, 3
PSA testing helps predict benign prostatic hyperplasia progression risk and excludes prostate cancer, according to the European Association of Urology 4