123 Patient Perception, Rather Than Magnitude of Objective Improvement, Predicts Desire for Treatment Amongst Men Undergoing Penile Shockwave Therapy
Authors: Omil-Lima D , Drozd A , Muncey W , Jesse E , Thirumavalavan N , Spirnak JP , Lengu I 
Published: April 2022

ABSTRACT

Introduction
Novel treatments options for refractory erectile dysfunction, including penile shockwave therapy, have recently been introduced. Despite uncertain clinical efficacy, direct-to-consumer marketing has resulted in increased patient interest in these treatments, often associated with high out-of-pocket costs.

Objective
In the current study, we sought to assess outcomes in men with refractory erectile dysfunction undergoing penile shockwave therapy, as well as patient's perception of treatment outcomes.

Methods
Community-dwelling men receiving care at a local county hospital were prospectively recruited to undergo penile shockwave therapy for treatment of refractory erectile dysfunction. Men underwent a total of six treatment sessions free of charge. Response to therapy was tracked utilizing the Sexual Health Inventory for Men (SHIM), with successful response defined as an increase in average SHIM score following treatment, as compared to baseline scores. Upon completion of treatment, defined as 4 out of 6 sessions or more, men were asked about their subjective perception of treatment benefit, including whether they would repeat treatment and recommend treatment to others. Logistic regression and Pearson's chi-squared test were used to determine whether objective treatment effect predicted men's attitudes towards penile shockwave therapy.

Results
A total of 23 men were prospectively recruited to our study. Of these, 19 patients (83%) completed 4 out 6 shockwave treatments. Based on increase in SHIM score, 13 men (68%) were deemed responders to therapy, while 6 men (32%) were deemed non-responders. Amongst all-comers, the median change in SHIM score before and after treatment was 0.7 points (interquartile range: 3 points). Amongst responders, the median increase was 1.3 points, while non-responders experienced a median decrease in SHIM score of 2 points after completion of treatment. No statistically significant differences were noted between responders and non-responders with regard to important patient characteristics such as age, BMI, and smoking status, as well as comorbidities including diabetes, peripheral arterial disease, and history of myocardial infarction. Amongst patients completing treatment, 50% noted subjective improvements, while 93% stated they would repeat treatment and recommend treatment to others. On univariate logistic regression, objective response to therapy, based on increase in SHIM score, failed to predict patient's subjective sense of improvement (OR=5, 95% CI 0.3-72.8, p=0.24) and the frequency subjective improvement was not statistically different amongst responders and non-responders (Pearson's chi-squared; p=0.22).

Conclusions
Objective, clinically significant improvement in SHIM scores was not seen amongst men undergoing penile shockwave therapy for erectile dysfunction. Despite this, men experienced subjective improvement and a high rate of desire to continue treatment and recommend treatment to others, which could not be predicted by objective response to treatment. Increased patient education is required in order to set treatment expectations for costly novel therapies.

Disclosure
No