What is the most appropriate initial treatment for a 42-year-old man with erectile dysfunction (ED), major depressive disorder (MDD), and coronary artery disease (CAD), who is taking isosorbide (isosorbide mononitrate) and aspirin (acetylsalicylic acid), and has recently experienced a stressful life event?

Management of Erectile Dysfunction in a Patient with Depression and Coronary Artery Disease

Daily tadalafil is the most appropriate treatment for this 42-year-old man with erectile dysfunction, major depressive disorder, and coronary artery disease who is taking isosorbide and aspirin. 1, 2

Assessment of the Patient's Condition

This patient presents with several key factors that influence treatment selection:

• 6-month history of erectile dysfunction with ability to achieve but not maintain erection
• Major depressive disorder, recently exacerbated by job loss
• Coronary artery disease requiring isosorbide therapy
• Abnormal nocturnal penile tumescence testing (suggesting organic etiology)

Treatment Rationale

Why Daily Tadalafil is Preferred

1. Cardiovascular Safety:

   • The patient is taking isosorbide (a nitrate), which creates a significant drug interaction concern with on-demand PDE5 inhibitors 3
   • Daily low-dose tadalafil (2.5-5mg) has been shown to have minimal hemodynamic effects compared to isosorbide mononitrate 4
   • Tadalafil's steady-state pharmacokinetics with daily dosing provides more stable plasma levels, potentially reducing risk of significant blood pressure fluctuations 1

2. Addressing Organic ED:

   • Abnormal nocturnal penile tumescence testing indicates an organic component to his ED 3
   • PDE5 inhibitors are recommended as first-line treatment for organic ED by the American Urological Association 3, 1

3. Psychological Benefits:

   • Daily tadalafil eliminates the need for timing medication with sexual activity, reducing performance anxiety 1
   • This approach may help address the psychological component related to his depression and recent job loss

Why Other Options Are Less Appropriate

1. Cognitive-behavioral therapy alone:

   • While CBT is effective for predominantly psychogenic ED and depression 3, this patient has abnormal nocturnal penile tumescence testing indicating organic etiology
   • CBT would be valuable as an adjunct to medical therapy, not as primary treatment 3

2. Daily paroxetine:

   • SSRIs like paroxetine can actually worsen erectile dysfunction 3
   • While appropriate for his depression, it would likely exacerbate his sexual dysfunction

3. Sildenafil as needed:

   • Contraindicated with nitrate therapy (isosorbide) due to risk of severe hypotension 5
   • The timing requirement may increase performance anxiety in a patient already experiencing psychological distress

4. Vacuum erection therapy:

   • While safe with his cardiovascular condition, this is typically considered after oral therapy has failed 3
   • May further increase performance anxiety and reduce spontaneity

Implementation Plan

1. Medication Management:

   • Start with tadalafil 2.5mg daily, potentially increasing to 5mg if tolerated and needed
   • Monitor blood pressure closely during initial treatment period
   • Consider consultation with cardiology to confirm safety with his specific cardiac status

2. Adjunctive Approaches:

   • Consider referral for psychological support to address depression and recent job loss
   • Encourage lifestyle modifications that benefit both ED and cardiovascular health:
     • Regular physical activity
     • Weight management if needed
     • Smoking cessation if applicable

3. Follow-up Plan:

   • Assess response after 4 weeks
   • Monitor for side effects including headache, flushing, and nasal congestion
   • Consider partner inclusion in treatment discussions with patient's permission

Important Precautions

• Cardiovascular Risk: The patient should be counseled that sexual activity represents moderate physical exertion (2.0-5.4 METs) 3
• Nitrate Interaction: Emphasize the importance of maintaining his prescribed dosage of both medications and not taking additional nitrates
• Depression Management: Ensure his depression is being adequately treated, as it can contribute to both ED and cardiovascular risk 6

By addressing both the organic and psychological components of his erectile dysfunction while ensuring cardiovascular safety, daily tadalafil represents the most appropriate treatment option for this patient.