Erectile dysfunction pre and post kidney transplant recipients in Duhok city; cross sectional study

Introduction Sexual dysfunction is a common problem in patients with chronic kidney disease. Disturbances in sexual function are noticed in early stages of chronic kidney diseases and deteriorate further as renal function declines. This is due to uremic effects, comorbid illness, anemia, hormonal disturbances, autonomic neuropathy, vascular diseases, hyperparathyroidism, hyperprolactinemia, side effects of medications, and psychosocial factors. Patients and method This is a cross-sectional study which included 59 male patients who underwent renal transplantation for more than 6 months. The International Index of Erectile Function (IIEF-5) was adopted in our study to record the erectile function. Results The mean age was 49.41 years, and the mean number of hemodialysis per month was 5.31. The cause of the chronic kidney disease was diabetes mellitus in 35.59%, glomerulonephritis in 20.34%, and hypertension in 16.95%, other causes were diagnosed in order of decreasing frequency. Most patients developed improvement in the erectile function after transplantation. There was significant correlation with 3 of the elements of the IIFE-5.i.e; penile hardness pre-penetration, Maintaining erection during intercourse, and Difficulty to maintain erection to complete the intercourse (p values 0.015, 0.011, and 0.023) respectively, and the overall improvement after transplantation which showed a p-value of less than 0.031, while there was no significant correlation with Confidence with erection and Satisfaction with intercourse before and after transplantation (p values 0.113 and 0.121) respectively. One of the patients (1.7%) developed severe dysfunction after that. Conclusion ED is common sequel of chronic kidney disease. The etiology is multifactorial and may be worsen by advanced age, presence of diabetes mellitus and prolonged duration of hemodialysis. Renal transplantation has a positive impact on sexual function and lead to improvement of erectile dysfunction. Erectile dysfunction that persists after kidney transplantation is usually attributed to multiple preexisting comorbidities.


Introduction
Sexual dysfunction (SD) is a common problem in patients with chronic kidney disease (CKD). Disturbances in sexual function are noticed in early stages of CKD and deteriorate further as renal function declines [1,2]. Sexual dysfunction has a major impact on the quality of life and it had been reported in both male and female patients with CKD. This greatly affects the social and the marital life of the affected patients [3][4][5][6].
Seventy percent of males have some forms of erectile dysfunctions (ED) during their life time. Other reported sexual problems may include reduced libido, difficulty in achieving orgasm and anejaculation [7].
The etiology of SD is often multifactorial, besides the uremic effects, factors such as comorbid illness, anemia, hormonal disturbances, autonomic neuropathy, vascular diseases, hyperparathyroidism, hyperprolactinemia, side effects of medications, and psychosocial factors all contribute to the existence of SD [1,2].
Renal transplantation prolongs life and improves the quality of life in patients with CKD. Because of normalization of the hormonal disturbances, renal transplantation improves the sexual health (e.g. libido), energy, and fertility [8][9][10][11].
However, after kidney transplantation, the prevalence of SD still remains 46% in both men and women.

Aim of the study
The aim of the study is to assess the erectile dysfunction in male patients before and after kidney transplantation by means of a validated, self-administered questionnaire.

Patients and method
This is a cross-sectional study which included 68 male patients who underwent renal transplantation for more than 6 months, patients with stable graft function were included. All were male patients aged 40 years or older and who attended regular visits to the transplantation clinic in Duhok kidney transplantation center from January 2018 to march 2019 were considered eligible and were included in this study.
A translated questionnaire to the native local language from the original version of five items of the International Index of Erectile Function (IIEF-5) which was adopted in our study.
Patients were given the questionnaire to answer it at home, data were collected before the transplantation and after transplantation.

Definitions
ED is defined as the inability to achieve or maintain an erection sufficient to allow satisfactory sexual intercourse. Scoring for each item was done from 0 to 5. The total score ranges from 0 to 25 points, and the cutoff points proposed by the authors are as follow: severe dysfunction when the score ranges between 0 and 7, moderate dysfunction when the score ranges between 8 and 11, mild-to-moderate dysfunction score ranges between 12 and 16, mild dysfunction between 17 and 21, and no dysfunction between 22 and 25. Erectile dysfunction is defined as an IIEF-5 score of less than 22.
The statistical calculations were done in Statistical Package for Social Sciences (SPSS 25:00 IBM: USA).
The descriptive purposes of our study is displayed in frequency and percentages for categorical data and mean and standard deviation for continuous variables.
Correlation were done using the two-tailed t-tests with 95% confidence interval, P values less than 0.05 were considered significant.
The work of this article has been reported in line with the STROCSS criteria [16].

Results
Our study included 59 kidney transplant male patients, their mean age was 49.41 years, and the mean number of hemodialysis per month was 5.31, Table 1.
The most cause of the chronic kidney disease was diabetes mellitus in 35.59%, followed by glomerulonephritis in 20.34%, hypertension in 16.95% of patients, and other causes were diagnosed in order of decreasing frequency, Fig. 1.
Most patients developed improvement in the erectile function after transplantation, there was a significant correlation with three of the elements of the IIFE-5 and the overall improvement after transplantation, Fig. 2 and 3, and Table 2.
The majority of patients had mild dysfunction before transplantation according to the IIEF-5 score, while after transplantation the majority of them reported a noticeable improvement, while one of the patients developed severe dysfunction, Table 3 & Fig. 2.

Discussion
Erectile dysfunction is defined by the National Institute of Health (NIH) Consensus Development Conference as the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Although laboratory based diagnostic procedures are available, it has been proposed that sexual function is best assessed in a naturalistic setting with patient self-reporting technique [17].
Renal failure is a major risk for erectile dysfunction and about half of patients with chronic renal failure may be impotent which is multifactorial but primarily organic. In addition to the uremic milieu, peripheral neuropathy, autonomic insufficiency, peripheral vascular disease and pharmacotherapy, all play an important role in the development of erectile dysfunction [18].
Our study showed that ED is more common and more severe among patients aged 45 years and in those with history of hemodialysis. Increased age is a well-known risk factor for ED, the importance of increased age on the prevalence of ED in the renal transplant population has been verified in several studies, Malavaud et al., and his colleagues studied 271 kidney transplant patients, they found that the  average age of those patients with ED was 49.2 years while those without ED was 44.5 years. They also found that ED is 3-4 times more likely to occur in those who are over 40 years old [19][20][21].
The most common cause of CKD in our study was diabetes mellitus, diabetes mellitus is also a major cause of ED. This is multifactorial and is thought to be caused by acceleration of angiopathy and neuropathy. Long duration of hemodialysis is also a major risk factor for ED. This has been attributed to permanent damage of cavernous vessels and smooth muscles sustained during the long course of renal failure [22,23].
Early transplantation is recommended because it is more effective with lower costs than hemodialysis. Maintaining erectile function should be another reason for early transplantation.
Regarding the role of kidney transplantation on sexual function, we found that majority of participant had improved ED post transplantation. There was significant correlation with 3 of the elements of the IIFE-5.i.e; penile hardness pre-penetration, Maintaining erection during intercourse, and Difficulty to maintain erection to complete the intercourse (p values 0.015, 0.011, and 0.023) respectively, and the overall improvement after transplantation which showed a p-value of less than 0.031, while there was no significant correlation with Confidence with erection and Satisfaction with intercourse before and after transplantation (p values 0.113 and 0.121) respectively. One of the patients (1.7%) developed severe dysfunction after that. Improvement of sexual function after kidney transplantation has been reported in several similar studies supporting our results [24][25][26][27][28].
In another more recent study of CKD patients receiving a spectrum of treatment such as peritoneal, hemodialysis, and renal transplant; renal transplant patients showed the most statistically significant   increase in IIEF score [26,28].
In addition to the normalization of hormonal and metabolic functions post-transplant, there is a significant improvement of the psychosocial parameters in transplant recipients, which have a major impact on the sexual function as well. It is important to note that many patients have a persistent ED post-transplant, this is probably due to the fact that transplant alone cannot eliminate all comorbidities affecting both renal and erectile functions [21,29,30].
There was no significant association between ED and the use of different types of medications in this study, this result was comparable to other study in this regard [31].

Source of funding
The author is the source of the funding.

Provenance and peer review
Not commissioned, externally peer reviewed.

Declaration of competing interest
No conflict of interest is present to be declared.