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Answer Key: Do You Know the Key Mechanisms and Risks of Lower Urinary Tract Symptoms for Men?

Kate Young

Answer Key:

  1. In men with significant irritative LUTS due to overactive bladder, which pharmacologic class is most appropriate?
    Correct Answer: D. Anticholinergics or β3 agonists
    α1-adrenergic blockers—such as tamsulosin, alfuzosin, and silodosin—act by relaxing the smooth muscle in the prostate stroma and bladder neck through selective inhibition of α1A-adrenergic receptors. This mechanism specifically addresses dynamic bladder outlet obstruction, which refers to the reversible narrowing of the urethral lumen caused by increased smooth muscle tone. These medications typically provide rapid symptom relief within 3 to 7 days and are considered first-line therapy for men with predominantly obstructive LUTS. They differ from 5α-reductase inhibitors, which act more slowly by reducing prostate size, and from anticholinergics or β3 agonists, which target bladder storage symptoms associated with detrusor overactivity.
  2. What is a controversial potential long-term risk of anticholinergic use for OAB?
    Correct Answer: B. Dementia
    Long-term use of anticholinergic medications—commonly prescribed for overactive bladder symptoms such as urgency and frequency—has been associated with an increased risk of cognitive decline and dementia, especially in older adults. Several observational studies2-4 have shown a dose-dependent relationship between prolonged anticholinergic use and the onset of dementia, with odds ratios ranging from 1.5 to 1.7. The proposed mechanism involves central nervous system penetration of anticholinergics like oxybutynin, which block muscarinic receptors involved in memory and cognition. However, this association remains controversial, as other studies have found no significant cognitive effects.5-6 
  3. Which of the following pathophysiologic mechanisms is unique to men and contributes to bladder outlet obstruction?
    Correct Answer: B. Prostatic urethral compression from androgen-driven hyperplasia
    Among the listed options, prostatic urethral compression due to benign prostatic hyperplasia (BPH) is the only mechanism specific to men. This condition involves hyperplasia of both glandular and stromal elements of the prostate, driven by the conversion of testosterone to dihydrotestosterone via 5α-reductase. As the prostate enlarges, it encroaches on the prostatic urethra, resulting in static obstruction—a mechanical narrowing that impedes urinary flow. This form of obstruction is a hallmark of male LUTS and is absent in women, who do not have a prostate gland. In contrast, detrusor overactivity, impaired neural control, and ATP-mediated bladder signaling are mechanisms that can affect both men and women. 

References:

  1. Wei JT, Dauw CA, Brodsky CN. Lower urinary tract symptoms in men: A review. JAMA. Published online July 14, 2025; doi:10.1001/jama.2025.7045
  2. Malcher MF, Droupy S, Berr C, et al. Dementia Associated with Anticholinergic Drugs Used for Overactive Bladder: A Nested Case-Control Study Using the French National Medical-Administrative Database. J Urol. 2022;208(4):863-871. doi:10.1097/JU.0000000000002804
  3. Zillioux J, Welk B, Suskind AM, Gormley EA, Goldman HB. SUFU white paper on overactive bladder anticholinergic medications and dementia risk. Neurourol Urodyn. 2022;41(8):1928-1933. doi:10.1002/nau.25037
  4. Coupland CAC, Hill T, Dening T, Morriss R, Moore M, Hippisley-Cox J. Anticholinergic Drug Exposure and the Risk of Dementia: A Nested Case-Control Study. JAMA Intern Med. 2019;179(8):1084-1093. doi:10.1001/jamainternmed.2019.0677
  5. Welk B, McClure JA. The Impact of Anticholinergic Use for Overactive Bladder on Cognitive Changes in Adults with Normal Cognition, Mild Cognitive Impairment, or Dementia. Eur Urol Open Sci. 2022;46:22-29. Published 2022 Oct 25. doi:10.1016/j.euros.2022.10.008
  6. Andre L, Gallini A, Montastruc F, et al. Anticholinergic exposure and cognitive decline in older adults: effect of anticholinergic exposure definitions in a 3-year analysis of the multidomain Alzheimer preventive trial (MAPT) study. Br J Clin Pharmacol. 2019;85(1):71-99. doi:10.1111/bcp.13734

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