Although not mandatory, questionnaires might be helpful to assess the presence or severity of ED, especially in those settings where the interviewer is not familiar with the condition and when a measurable clinical response is needed. Although questionnaires are a subjective tool with information from the patient’s interpretation and self-response, it can serve as objective data to assess treatment response or disease progression.

One of the most widely used questionnaires is the International Index of Erectile Function (IIEF); this is a 15-item questionnaire covering five domains including desire, erection, orgasm, ejaculation and satisfaction, with scores ranging from 1 to 5 per question.

A lengthy questionnaire, it is often used in clinical trials, but might be a tedious task during consultation. An abbreviated version of this questionnaire is the IIEF-Erectile Function Domain, one comprised of six questions focused on the erection domain and sexual satisfaction with a maximum score of 30. Men with a normal erectile function will have a score of 25.

Another short questionnaire derived from the IIEF is called the Sexual Health Inventory for Men (SHIM) includes five questions on erectile function related to the prior 6 months, and has a total score ranging from 5 to 25: a score of 22–25 means normal erectile function, 17–21 mild ED, 12–16 mild to moderate ED, 8–11 moderate ED, and <7 severe ED.

It is not uncommon to find risk factors unknown by the patient such as diabetes, dyslipidemia, or hypertension. In 1999, a panel of experts elaborated the guidelines for cardiovascular evaluation in patients with ED, then revised and published them for the second Princeton consensus.

These guidelines recommend an evaluation for ED patients, and establish three levels of cardiovascular risk:

• Low-risk category: Asymptomatic; <3 risk factors for coronary artery disease ([CAD] excluding gender); uncomplicated past myocardial infarction (MI); left ventricular dysfunction (LVD)/ congestive heart failure (CHF) (New York Heart Association [NYHA] class I); mild, stable angina (evaluated and/or being treated); post-successful coronary revascularization; controlled hypertension; mild valvular disease.
• Intermediate-risk category: >3 risk factors for CAD (excluding gender); recent MI (>2, <6 weeks); moderate, stable angina; LVD/CHF (NYHA class II); non-cardiac sequelae of atherosclerotic disease (e.g., stroke, peripheral vascular disease).
• High-risk category: High-risk arrhythmias; unstable or refractory angina; recent MI (<2 weeks); LVD/CHF (NYHA class III/IV); uncontrolled hypertension; moderate-to-severe valvular disease; hypertrophic obstructive, and other cardiomyopathies.

Additionally, each level has corresponding management recommendations:

• Low-risk category: Primary care management, consider all first-line therapies, reassess at regular intervals (6–12 months).
• Intermediate-risk category: Specialized CV testing (e.g., exercise treadmill test [ETT], Echo), restratification into high risk or low risk based on the results of CV assessment.
• High-risk category: Priority referral for specialized CV management, treatment for sexual dysfunction to be deferred until cardiac condition stabilized and dependent on specialist recommendations.

Physical Examination A focused physical examination is mandatory in assessing the patient complaining of ED. Although not always revealing the exact etiology, it will certainly help in determining risk factors such as gynecomastia, hair distribution, abdominal circumference, peripheral pulses and measurement of the blood pressure and weight.

Special attention should be given to external genitalia including penile size, consistency, presence of penile plaques, foreskin retraction, prepubic fat, and testis shape and consistency. Rectal exam is important to assess rectal tone and reflexes as well in men over 50 years old who have a risk for prostate cancer.

One important aspect when evaluating a patient with ED is to consider the degree of cardiovascular risk. Laboratory Tests In view of the strong relationship of ED with vascular risk factors, it is important to dosed fasting glucose and lipids in every patient consulting for ED if these have not already been performed. Serum testosterone needs to be dosed, especially in those subjects with low libido and/or poor response to PDE5-Is, although many clinicians consider it mandatory in every patient with ED, since sexual function could be a marker for hypogonadism.

This controversy rises from many factors: clinical manifestations of hypogonadism is diverse and rarely complete, severity is also variable, and more than one laboratory measurement is required as there is a 40% rate of false positive results.

If this test is not part of the initial assessment, a more complete hormonal evaluation could be ordered when considering additional testing. Since the majority of the circulating testosterone is bound to the SHBG and to the albumin (bioavailable testosterone), the free portion of circulating testosterone is most important in terms of function, though a reliable laboratory dosing is very expensive and not widely performed. Calculated free testosterone (CFT) is a safe and reliable method to assess free testosterone using the values of total testosterone and SHBG on a table designed by Vermuelen.

Gonadotrophins (LH and FSH), dehydroepiandrosterone (DHEA) and its sulfated form (DHEAS), prolactin, and thyroid hormones are only part of advanced hormonal assessment in special endocrine situations and treatment monitoring; routine use of these studies should be discouraged.