Endocrinology, Diabetes, and Metabolism· Topic 4.5 Testes and male reproductive health· 4.5.5

Erectile dysfunction

Erectile dysfunction is the inability to achieve or maintain an erection sufficient for satisfactory sexual performance for at least 6 months, most often from vascular, neurologic, medication, endocrine, or psychological causes, and is a significant marker of coronary risk. Diagnosis is clinical from history and exam with targeted labs, and first-line treatment is an oral phosphodiesterase-5 inhibitor unless the patient takes nitrates.

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What this article covers

  • Overview

    Erectile dysfunction (ED) is the inability to achieve or maintain an erection necessary for satisfactory sexual performance, persisting for at least 6 months.

  • Epidemiology

    ED is the most common male sexual disorder and increases in prevalence with age, reflecting the cumulative burden of vascular, neurologic, and endocrine risk factors across the decades.

  • Risk factors

    Coronary/peripheral atherosclerosis, the leading organic cause, from impaired penile arterial blood flow.

  • Pathophysiology

    Sexual stimulation activates the autonomic erection center, sending parasympathetic (S2-S4) and sympathetic (T12-L2) input to the cavernous nerves that regulate penile blood flow.

  • Clinical features

    Difficulty achieving or maintaining an erection sufficient for satisfactory sexual performance, persisting for at least 6 months, is the defining feature.

  • Differential diagnosis

    Psychogenic ED: situational, worse with intercourse than masturbation, with preserved nocturnal and early-morning erections, unlike organic ED where nocturnal erections are typically lost.

  • Diagnosis

    ED is a clinical diagnosis established by a detailed history and physical examination documenting difficulty achieving or maintaining an erection sufficient for satisfactory sexual performance for at…

  • Management

    First, address reversible contributing factors: review the medication list for ED-associated drugs and consider switching or stopping the offending agent, and initiate lifestyle modification (smoking…

  • Complications

    Missed cardiovascular risk-factor identification, since ED without clear etiology is a marker for undiagnosed coronary arteriosclerosis; failure to evaluate risk factors delays cardiovascular risk reduction.

  • Prognosis

    Most men with ED respond well to first-line oral PDE5 inhibitor therapy, with similar efficacy across the approved agents.

  • Prevention

    Screen for and treat to target cardiovascular risk factors (blood pressure <130/80 mm Hg, LDL cholesterol per atherosclerotic risk category, hemoglobin A1c individualized target in diabetes) as part…

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