Neurogenic ED remains difficult to diagnose and treat effectively. It is important to realize that many men with neurologic disorders may have ED related to disease related factors separate from the insult to the neuro-erectile pathway. These disease related factors must be addressed prior or simultaneously with pharmacologic and/or surgical therapy to effectively treat their SD. As awareness of the complexities of normal sexual function increase so will the recognition of SD in this population. This movement will lead to improved quality of life in men with neurologic disorders, as proven by the strong link between sexual function and quality of life.
2 inability of the adult male to achieve or sustain a penile erection or, less commonly, to ejaculate after achieving an erection. Several forms are recognized. Functional impotence has a psychological basis. Organic impotence includes vasculogenic, neurogenic, endocrinic, and anatomical factors. Anatomical impotence results from physically defective genitalia. Atonic impotence involves disturbed neuromuscular function. Poor health, old or advancing age, drugs, smoking, trauma, and fatigue can induce impotence. Also called erectile dysfunction, impotency. impotent, adj.
The severity of ED has been correlated with the extent of CVD. Banks et al reported that the risk of future CV events increased progressively according to ED severity.28 This was shown in both men with and without known CVD at baseline and after controlling for confounders. Solomon and colleagues found an inverse correlation between international index of erectile function (IIEF) scores and plaque burden seen on coronary angiography.29 In addition, Yaman et al demonstrated a significant correlation between ED severity on IIEF questionnaires and coronary artery calcification.30
Commercials for drugs to improve “low T,” or testosterone, the male hormone, are now vying for airtime, but they address desire, not performance. "Male hormone is not an approved treatment for erectile dysfunction," notes Bennett. "It may be used to increase desire in men who have low testosterone, but it doesn’t improve blood flow to an erection." A doctor can do a blood test to check you for low testosterone, but it is a rare cause of ED. Hormone therapy with injections, patches, or gels applied to the skin may improve mood and sex drive, but it likely won’t fix any mechanical issues. Also, testosterone drugs should not be used by men with prostate cancer. Side effects include acne, breast enlargement, prostate enlargement, and fluid retention.
Iatrogenic hypotension can occur in men in neurodegenerative disease using sildenafil (49). Hussain et al. placed men with PD and MSA on sildenafil and recorded blood pressure before and after. Half of the 12 MSA patients developed postural hypotension, while none of the twelve PD patients did. Since MSA can be difficult to distinguished diagnostically from PD, baseline blood pressure measurements prior to prescribing the medication and seeking medical assistance if symptomatic hypotension occurred was recommended for all patients with PD, and MSA. Of note, none of the men with MSA who developed hypotension discontinued sildenafil use due to its effectiveness at improving their erections.
There have been rare reports of priapism (prolonged and painful erections lasting six or more hours) with the use of PDE5 inhibitors. Patients with blood cell diseases such as sickle cell anemia, leukemia, and multiple myeloma have higher than normal risks of developing priapism. Untreated priapism can cause injury to the penis and lead to permanent impotence. Therefore, if your erection lasts four hours, you should seek emergency care.
Oral therapies via the PDE5i sildenafil, vardenafil, and tadalafil have been proven to be generally safe and effective in select NED populations. The majority of the treatment effectiveness data has been generated in the SCI population. Data regarding the use of PDE5i outside of the SCI population is lacking (58). Furthermore, the ED that exists in the population with neurologic disorders is often multifactorial and may be caused by psychogenic, psychosocial, hormonal, medication-related and disability-related factors. A careful evaluation of each patient must be performed to isolate these factors prior to initiating vasoactive therapy.
An alprostadil cream that patients apply into the tip of the penis (the urethral meatus, the opening that urine passes through) is currently available in the UK and Europe. It is currently under review by the U.S. Food and Drug Administration (FDA). After application of the cream, an erection occurs within five to 30 minutes, and the erection lasts one to two hours in men who respond to the cream. Doctors recommend that one use the cream for a maximum frequency of two to three times per week and no more frequent than once every 24 hours. It has essentially the same contraindications and side effects as the other formulations of alprostadil. The cream may cause vaginal burning in roughly 4% of partners. Men should not use alprostadil cream for sexual intercourse with women of childbearing potential unless a condom is used. Researchers have performed controlled trial studies to evaluate the safety and effectiveness of this drug. Overall, 52% of men reported improvement in their erections compared to 20% of men receiving placebo. A later analysis demonstrated that 36% of men using the alprostadil cream had a clinically relevant improvement in vaginal penetration ability and 31% clinically relevant improvement in ability to have successful intercourse to ejaculation.
Adverse effects related to PDE5i use with mild-moderate and transient (58). Furthermore, side effects usually attenuate if use is not discontinued. Autonomic dysreflexia, a life-threatening phenomenon characterized by bradycardia, hypertension, facial flushing and headaches associated with SCI lesions above T6, has not been reported with use. However, hypotension leading to dizziness in individuals treated with sildenafil has been noted with high thoracic and cervical levels of injury (72). No adverse events were noted within the study; however, the dizziness was reported by use of sildenafil 50 mg in the cervical LOI and 100 mg in the thoracic LOI patients. Headache is the most reported side effect of all PDE5i, followed by dyspepsia and flushing. Priapism, and death have not been reported after use of PDE5i by SCI patients.
Prior to starting with treatment of erectile dysfunction, it is important to make sure that it is safe from a medical standpoint to participate in sexual activity. Sexual activity is physical exertion, and in some men with significant heart disease, this increase in physical exertion can increase the risk of a heart attack. Thus, it is very important to discuss your cardiovascular risks with your doctor prior to trying any medication or treatment for erectile dysfunction.