Evaluate the effect of microvaricocelectomy on sperm DNA fragmentation index in infertile men

The objective was to evaluate the effect of microvaricocelectomy on sperm DNA fragmentation index (DFI) in infertile men. Method: A controlled observational study was based on 205 patients who sought medical consultation at Hanoi Medical University Hospital.

JOURNAL OF MEDICAL RESEARCH EVALUATE THE EFFECT OF MICROVARICOCELECTOMY ON SPERM DNA FRAGMENTATION INDEX IN INFERTILE MEN Nguyen Hoai Bac1, Nguyen Cao Thang1, Nguyen Viet Anh2 Hanoi Medical University Hospital, 2Hanoi Medical University The objective was to evaluate the effect of microvaricocelectomy on sperm DNA fragmentation index (DFI) in infertile men Method: A controlled observational study was based on 205 patients who sought medical consultation at Hanoi Medical University Hospital In which, 142 men were diagnosed with infertility who had unilateral varicocele belonged to the varicocele group and 63 men with normal reproductive health belonged to the control group Results: The mean sperm DFI was significant higher in the varicocele group compared with that in the control group (31.8 ± 18.8 compared with 22.6 ± 10.6, respectively, p = 0.0002) In the varicocele group, sperm DFI was considerably reduced after surgery (31.8 ± 18.8% pre-surgery to 22.6 ± 10.6 postsurgery with p = 0.0001) The improvement was evidently observed in patients with severely damaged sperm DFI (≥ 30%) The mean post-operative sperm DFI was comparable with that in the control group (25.1 ± 14.9 vs 22.6 ± 10.6, p = 0.13) There was no remarkable differences in the percentage of severe sperm DFI (≥ 30%) between the varicocele group after surgery and the control group (26.7% vs 20.6% respectively, p > 0.05) A negative correlation between the change in post-operative sperm DFI and the level of pre-operative sperm DFI was also observed in this study (r = - 0.77, p = 0.0001 ) Conclusion: Microsurgical varicocelectomy reduced significantly the sperm DFI, therefore, this surgery should be indicated early for infertile men with varicocele Keywords: Varicocele, varicocelectomy, semen analysis, sperm DNA integrity, DFI I INTRODUCTION Varicocele is the abnormal dilation of Recent studies showed another possible the veins in the pampiniform plexus which is explanation, which is the elevation of reactive commonly caused by the reflux of the left renal oxygen species (ROS) and sperm DNA vein on the left side and the inferior vena cava damage or sperm DNA fragmentation index on the right side Varicocele is found in 19 - (DFI) DFI provides more credibility because, 41% of primary infertile men and up to 45 - 84% unlike standard semen analysis, DFI exhibits in secondary infertile men [1] The etiologies of low biological variability and has superior varicocele which affect reproductive health is predictive value on reproductive outcomes not completely understood Some proposed Many researchers have evaluated the effect mechanisms are the dysfunction of the of varicocele on DFI and the benefit of spermatogenesis due to altered blood flow and varicocelectomy on infertile men with varicocele hypoxia, reflux of the metabolic products from [3] However, the results remain controversial adrenal glands, increased scrotal temperature, Therefore, the exact benefit of surgical repair etc [2] treatment for varicocele on infertile men needs Corresponding author: Nguyen Hoai Bac, Hanoi Medical University Hospital Email: drbac.uro@gmail.com Received: 27/11/2018 Accepted: 12/03/2019 22 further assessment In Vietnam, there have been many studies on the adverse impact of varicocele on conventional semen analysis [4] However, few have evaluated the relation of varicocele and JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH DFI in infertile men The majority of them were conducted on small sample size and absent of the control group Therefore, the aim of our study is to evaluate the effect of surgical varicocelectomy on sperm DFI in infertile men II METHODS - Had subclinical varicocele (grade 0) or had clinical varicocele with normal ultrasonography - Laboratory tests were not performed at Hanoi Medical University’s lab Inclusion criteria of the control group - Having good health determining via periodical health examination Time and location - Their partner are having pregnancy Our study was conducted from December 2013 to August 2018 at Hanoi Medical University Hospital examination and ultrasonography Material and method Variables A controlled observational study based on 205 men who had been examined at Hanoi Medical University Hospital, in which 142 infertile men with varicocele belonged to the varicocele group and 63 men with normal reproductive health belonged to the control - Without varicocele confirmed by clinical Sperm DNA fragmentation index (DFI) is based on the evaluation of the SCD technique which was generated with Halosperm kit Data analysis Collected data was processed and analyzed by STATA 13 group Inclusion criteria of varicocele group - Diagnosed with infertility according to the WHO manual 2000 - Diagnosed with unilateral varicocele confirmed on clinical examination and ultrasound - Had sufficient laboratory tests Exclusion criteria of varicocele group All results were expressed as the mean ± SD Difference between groups was estimated by the paired sample T-student test for normal distribution and Mann Whitney test for non-normal distribution All hypothesis testing was considered statistically significant if p < 0.05 III RESULTS General features of the patients Table General features of the varicocele group and the control group Varicocele group (n = 142) n (%) (Mean ± SD) Control group (n = 63) n (%) (Mean ± SD) p 29.8 ± 5.4 28.9 ± 4.2 0.07 ≤ 30 87 (61.2) 26.6 ± 2.7 42 (66.7) 26.6 ± 2.6 0.41 > 30 55 (38.7) 34.9 ± 4.5 21 (33.3) 33.6 ± 2.7 Variables Age (years) JMR 118 E4 (2) - 2019 23 JOURNAL OF MEDICAL RESEARCH Varicocele group (n = 142) n (%) (Mean ± SD) Control group (n = 63) n (%) (Mean ± SD) p BMI (kg/m2) 142 21.9 ± 2.4 63 22.5 ± 2.5 0.07 Avg testicular volume(ml) 12.8 ± 3.8 13.7 ± 3.8 0.08 Variables The mean age of the varicocele group and the control group were 29.8 ± 5.4 and 28.9 ± 4.2, respectively The mean BMI of the two groups were also similar The average testicular volume of the two groups was similar and within normal range Measuring sperm DFI of the patients Table Sperm DFI of varicocele group and control group Varicocelegroup Variables Control group p n (%) Mean ± SD n (%) 142 31.8 ± 18.8 63 22.6 ± 10.6 0.0002 < 15 22 (15.5) 11.1 ± 2.3 16 (25.4) 11.8 ± 2.2 0.16 15 - 30 55 (38.7) 21.6 ± 4.2 34 (53.9) 21.3 ± 4.8 0.35 ≥ 30 65 (45.8) 47.4 ± 16.8 13 (20.6) 39.5 ± 6.4 0.05 DFI (%) Mean ± SD The mean DFI of the varicoecele group was significantly higher than the controls (31.8% ± 18.8% and 22.6 ± 10.6%, respectively, with p = 0.0002) The effect of microvaricocelectomy on sperm DFI Table Change of DFI after the surgery Presurgery Postsurgery n Mean ± SD Mean ± SD n 90 34.4 ± 20.9 25.1 ± 14.9 < 15 15 10.8 ± 2.1 15 - 30 27 ≥ 30 48 Variables DFI (%) Mean ± SD p1 (pre&postsurgery) p2 (postsurgery&control) 63 22.6 ± 10.6 0.0001 0.13 23.4 ± 13.9 16 11.8 ± 2.2 0.002 0.001 21.4 ± 4.3 22.4 ± 13.8 34 21.3 ± 4.8 0.36 0.33 49.0 ± 18.0 27.1 ± 15.9 13 39.5 ± 6.4 0.0001 0.004 Control After the surgery, mean DFI significantly declined from 34.4 ± 20.9% to 25.1 ± 14.9% with p = 0.0001 The improvement was evidently observed in patients with severely damaged sperm DFI However, patients with moderate or mild sperm DNA fragmentation experienced no improvement The level of post-surgery sperm DFI became equivalent to that of the control group (25.1 ± 14.9 % versus 22.6 ± 10.6 % with p = 0.13) 24 JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH p > 0.05 Chart Ratio of DFI in both groups No difference was observed in the proportion of patients with severely damaged sperm DNA (DFI ≥ 30) in both group (26.7% and 20.6% with p > 0.05) Chart Correlation of pre-surgery DFI and the change of DFI post-surgery A negative correlation was observed in the change in DFI and the level of DFI pre-surgery Higher pre-surgery DFI associated with greater improvement post-surgery ( r = - 0.77, p = 0.0001*) IV DISSCUSSION This study involved 142 infertile men with clinical varicocele who had the mean age of 29.9 ± 5.5 (year) and 63 men of the control group with the mean age of 28.8 ± 4.3 (year) (Table 1) It was appropriate to determine JMR 118 E4 (2) - 2019 the effect of varicocele on semen quality due to the fact that the majority of patients were in reproductive age Previous authors also studied on the group of patients similar to this study (Abdel-Meguid et al and Ghazi et al) [5], 25 JOURNAL OF MEDICAL RESEARCH [6] The mean BMI of the varicocele group and the control group were also identical This was the basis to assess the impact of varicocele on the sperm DNA integrity on the varicocele group compared with normal fertile men Conventional semen analysis is a standard test to assess male reproductive function However, it has many limits including high biological variability and can be affected by the patient’s duration of sexual abstinence and mental state, etc In recent years, with the development of genetics and molecular biology, sperm DNA damage has been evaluated and considered a promising biomarker for infertility Sperm DNA fragmentation index (DFI) has been proved to be superior to the conventional semen analysis that it exhibits a lower degree of biological variability and has more predictive value in pregnancy rate [3] Previous studies have proved the elevation of sperm DFI in men with varicocele In a prospective controlled study which compared the level of sperm DNA damage between infertile men with varicocele and controls, the results demonstrated a significant increase in DFI of the varicocele group (25% and 15%, respectively with p < 0.05) [7] Similarly, in our study, the mean DFI of the varicocele group was 31.8 ± 18.8% which is remarkably higher than the controls at 22.6 ± 10.6 % with p = 0.002 (Table 2) Many studies and meta-analyses have shown evidence supporting the benefit of varicocelectomy on sperm DFI In 2011, Zini et al displayed the improvement of sperm DNA damage in infertile men after varicocelectomy In to months after the surgery, the mean DFI significantly declined from 18 ± 11% to 10 ± 5% in months and to ± 3% in months with p = 0.0015 These results indicated that varicocelectomy enhances the 26 spermatogenesis and sperm DNA integrity, which explained the higher pregnancy rate in previously infertile couple [3] More recently, a meta-analysis on 277 patients who were indicated with surgical varicocelectomy also demonstrated that the treatment considerably improved sperm DFI with the mean difference of 3.37% (36.4 ± 21.4% pre-operative compared with 23.8 ± 14% post-operative, p = 0.0001) [8] In our study, there was a sharp decline in sperm DFI after the surgery from 34.4 ± 20.9 % to 25.1 ± 14.9 % The difference was statistically significant with p = 0.0001 (Table 3) When comparing the postoperative sperm DFI with that of the control group, we noted that after surgery, there was no remarkable difference in sperm DFI between the two groups (25.1 ± 14.9 compare to 22.6 ± 10.6 with p = 0.13) It suggested the normalizing trend of DFI after ligation of spermatic veins (Table 3) In addition, the percentage of severe sperm DFI (≥ 30%) post-operative was not significantly different from that of the control group (26.7% versus 20.6%, p > 0.05) (Chart 1) These results confirmed the effect of microvaricocele on sperm DFI in infertile men with varicocele Regarding the improvement of postoperative DFI according to subgroup of preoperative sperm DFI, we noticed a visible improvement in the severe subgroup (DFI ≥ 30%) (49.0 ± 18.0 pre-operative vs 27.1 ± 15.9 post- operative, p = 0.0001) In contrast, a similar trend was not recognized in the two remain subgroups (Table 3) Interestingly, in the linear regression model, a significant negative correlation was found between the pre-operative sperm DFI level and the change in DFI after surgery The higher pre-operative DFI level resulted in the greater improvement of the post-operative sperm JMR 118 E4 (2) - 2019 JOURNAL OF MEDICAL RESEARCH DFI (r = - 0.77, p = 0.0001) (Chart 2) This finding supported previous results, Kadioglu et al revealed an association between higher preoperative DFI and a larger decrease in postoperative DFI (r = −0.42, p < 0.01) [9] Our results are in agreement with previously published literatures as mentioned above However, there remain several limitations in this study such as the non-randomized design or further investigation of the pregnancy rate of the patients V CONCLUSION Surgical varicocelectomy resulted in improved semen quality which is demonstrated by the level of DFI Indication of varicocelectomy should be based on the level of sperm DNA damage REFERENCE Mohammed, A and F Chinegwundoh (2009), Testicular varicocele: an overview Urol Int, 82(4), 373 - 379 Ficarra, V., et al (2012), Varicocele repair for infertility: what is the evidence? Curr Opin Urol, 22(6), 489 - 494 Zini, A., et al (2011), Effect of microsurgical sperm varicocelectomy chromatin and DNA on human integrity: prospective trial Int J Androl, 34(1), 14 - 19 JMR 118 E4 (2) - 2019 a Bac, N.H., B.C Vin, and H Long (2016) Tác động thắt tĩnh mạch tinh vi phẫu lên độ phân mảnh ADN tinh trùng bệnh nhân vô sinh nam giãn tĩnh mạch tinh Hội nghị vô sinh nam Nam khoa 2016 TP HCM Abdel-Meguid, T.A., et al (2011), Does varicocele repair improve male infertility? An evidence-based perspective from a randomized, controlled trial Eur Urol, 59(3), 455 - 461 Ghazi, S and H Abdelfattah (2011), Effect of microsurgical varicocelectomy on sperm DNA fragmentation in infertile men Middle East Fertility Society Journal, 16(2), 149 - 153 Saleh, R.A., et al (2003), Evaluation of nuclear DNA damage in spermatozoa from infertile men with varicocele Fertil Steril, 80(6), 1431 - 1436 Wang, Y.J., et al (2012), Relationship between varicocele and sperm DNA damage and the effect of varicocele repair: a metaanalysis Reprod Biomed Online, 25(3), 307 314 Kadioglu, T.C., E Aliyev, and M Celtik (2014), Microscopic varicocelectomy significantly decreases the sperm DNA fragmentation index in patients with infertility Biomed Res Int, 2014, 695 - 713 27 ...JOURNAL OF MEDICAL RESEARCH DFI in infertile men The majority of them were conducted on small sample size and absent of the control group Therefore, the aim of our study is to evaluate the effect of. .. proved the elevation of sperm DFI in men with varicocele In a prospective controlled study which compared the level of sperm DNA damage between infertile men with varicocele and controls, the results... the improvement of sperm DNA damage in infertile men after varicocelectomy In to months after the surgery, the mean DFI significantly declined from 18 ± 11% to 10 ± 5% in months and to ± 3% in