Evaluation Of Fractional Carbon Dioxide Laser For Treatment Of Female Stress Urinary Incontinence

PurposeStress urinary incontinence(SUI)is a common disease.In the field of urogynecology,the thermal effect of the laser can promote the remodeling of vaginal mucosal tissue and enhance the support of the pelvic floor thus improve female SUI.It is controversial to improve female SUI by vaginal fractional carbon dioxide(CO2)laser.There is few cogent evidence to illustrate the role of fractional CO2 laser in female SUI.This study aimed to evaluate the efficacy and safety of vaginal fractional CO2 laser treatment for female SUI,explore the most suitable patients for the therapy,and eventually provide evidence for further clinical application.MethodsThis study is a prospective,single-centered,participant-blinded,randomized controlled clinical trial,which was conducted at Qilu Hospital of Shandong University from April 2022 to February 2023.A total of 128 participants were enrolled and assigned to either the laser group or the sham group randomly,with 64 participants in each group.Participants in the laser group underwent vaginal fractional CO2 laser treatment for 3 times,while participants in the sham group underwent identical technique with blocked laser,with each interval of 28±4 days.Baseline evaluation was conducted before the intervention,tolerance evaluation conducted during the intervention,and efficacy evaluation conducted at 1 month,3 months and 6 months after the intervention.The safety was evaluated throughout the trail.Pre-specified subgroup analysis including age,BMI,SUI duration,SUI degree,and menopause based on treatment efficiency at the 3th month follow-up.The primary outcome measure was the efficacy of the intervention,while secondary outcome measures included the pad quality of the 1-hour urine pad test,symptoms,and questionnaire scores related to the quality of life.Binomial regression and poisson regression were used to compare the efficacy of different groups,and generalized estimating equation linear models were used to evaluate repeated measures of continuous variables.ResultsEffective rate was 83.87%in the laser group and 42.37%in the sham group at the 1st month follow-up,with the rate difference of 43.19%,95%CI(27.45%,58.94%),and the relative risk of 3.80,95%CI(2.10,6.90),P<0.001.The effective rate was 51.61%in the laser group and 16.95%in the sham group at the 3th month follow-up,with the rate difference of 33.76%,95%CI(17.85%,49.67%),and the relative risk of 2.97,95%CI(1.63,5.43),P<0.001.The effective rate was 27.42%in the laser group and 10.17%in the sham group at the 6th month follow-up,with the rate difference of 23.12%,95%CI(7.83%,38.41%),and relative risk of 2.98,95%CI(1.27,7.10),P=0.014.The secondary outcome included pad quality based on the 1-hour urine pad test,and scores of International Consultation of Incontinence Questionnaire-Short Form(ICI-Q-SF),Incontinence-specific Quality of Life(IQOL)and King’s Health Questionnaire(KHQ).The intervention effect was estimated based on the generalized estimation equation.The laser group had significantly lower pad quality at the 1st month(P<0.001),3th month(P=0.001),and 6th month follow-up(P=0.048),and lower ICI-Q-SF scores at the 1st month(P<0.001),3th month(P=0.007),and 6th month follow-up(P=0.013)than that in the sham group,suggesting that the laser group had better improvement in SUI symptoms than the sham group did.For the analysis of IQOL and KHQ scores based on the generalized estimating equations,the laser group was significantly better than the sham group in role,social,physical limitations,and severity measures at the 1st month,3th month,and 6th month follow-up compared with baseline(P<0.05).However,no significant differences were observed between the laser and sham groups in emotion,personal relationships,and sleep or energy(P>0.05).Both the primary and secondary outcome demonstrated a decreasing trend in efficacy with time(P<0.05),and stable efficacy was not observed during the 6-month follow-up.Subgroup analysis indicated the laser intervention was effective for the women with mild and moderate SUI(P<0.001),but not for the severe and very severe SUI.(P=0.872,P for interaction=0.065).Significant differences were not observed in other subgroups(P>0.1).The tolerability evaluation was the visual analogue scale of pain,and the safety evaluation was the incidence rate of adverse events,which both showed no differences between the laser and sham groups(P>0.05).ConclusionsFor treating female SUI,vaginal fractional CO2 laser is effective in the short term,with good tolerance and safety,while the efficacy had a downward trend over time.It may be more effective for the women with mild to moderate SUI.