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Table of Contents
ORIGINAL ARTICLE
Year : 2022  |  Volume : 33  |  Issue : 4  |  Page : 170-175

Efficacy and safety of Pulsed Electromagnetic Field (PEMF) stimulation in the treatment of urinary symptoms in women with urinary incontinence


Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran

Date of Submission24-Aug-2021
Date of Decision05-Jan-2022
Date of Acceptance26-Jan-2022
Date of Web Publication30-Nov-2022

Correspondence Address:
Samaneh Esmaeili
Urology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht
Iran
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/UROS.UROS_123_21

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  Abstract 


Purpose: There are different approaches to the treatment of urinary incontinence (UI), including pharmacological, nonpharmacological, and surgical methods. Pulsed electromagnetic field (PEMF) stimulation is a nontraditional and noninvasive type of treatment, which is gaining increasing popularity in healthcare departments for UI treatment. Materials and Methods: In this quasi-experimental study, women (age ≥21 years) with lower urinary tract symptoms (LUTS) were assigned to three groups regarding the UI type (urgency, stress, and mixed UI). The Bristol Female LUTS (BFLUTS) questionnaire was used to evaluate the UI severity. The patients were treated with PEMF stimulation twice per week up to 6 weeks. The results were evaluated at three and 6 months posttreatment. Results: Ninety women completed 6 months of follow-up in this study. The mean age of the participants was 58.5 ± 13.9 years. Of 90 patients, 61 (67.8%) had mixed UI, 22 (24.4%) had urge UI, and 7 (7.8%) had stress UI. There were significant differences between the groups regarding the frequency of leakage from baseline to 3 and 6 months after treatment; the reduction of leakage severity was only nonsignificant in the stress UI group (P = 0.368). Based on the results, the number of used pads reduced from 4.18 ± 3.00 to 1.08 ± 2.03 (P < 0.001); this reduction was also significant in each of the groups. The mean BFLUTS score reduced from 7.42 ± 2.53 at baseline to 5.56 ± 2.37 and 3.00 ± 2.33 at 3 and 6 months after treatment, respectively (P < 0.001). No significant complications were detected in the groups. Conclusion: The PEMF stimulation is a safe and effective approach for reducing the symptoms of patients with UI. The best response to treatment was reported at 6 months posttreatment. Therefore, it is recommended to use PMEF stimulation as a noninvasive treatment along with routine therapies.

Keywords: Pulsed electromagnetic field stimulation, urinary incontinence, women


How to cite this article:
Madani AH, Chafjiri FM, Esmaeili S, Madani ZH, Leili EK. Efficacy and safety of Pulsed Electromagnetic Field (PEMF) stimulation in the treatment of urinary symptoms in women with urinary incontinence. Urol Sci 2022;33:170-5

How to cite this URL:
Madani AH, Chafjiri FM, Esmaeili S, Madani ZH, Leili EK. Efficacy and safety of Pulsed Electromagnetic Field (PEMF) stimulation in the treatment of urinary symptoms in women with urinary incontinence. Urol Sci [serial online] 2022 [cited 2023 Feb 6];33:170-5. Available from: https://www.e-urol-sci.com/text.asp?2022/33/4/170/362476




  Introduction Top


The International Continence Society defines urinary incontinence (UI) as any type of involuntary urinary loss that severely decreases the patient's quality of life (QoL). UI symptoms generally vary among women, who are at a higher risk compared to men. However, in both sexes, the UI prevalence increases with advancing age. As UI has a significant impact on health-related QoL, it may negatively affect the quality of patients' personal and social activities.[1],[2],[3],[4]

Stress UI (SUI), urge UI (UUI), and mixed UI (MUI) are the three most common UI types.[5] Evidence shows that UI prevalence and its different types vary in different communities.[6] It has been reported that 10%–55% of women, who are in the age range of 15–64 years, experience UI symptoms, whereas the corresponding rate is up to 77% in elderly women,[6],[7] with SUI showing the highest prevalence.[6],[8] The current estimates suggest that more than 200 million women are affected by UI worldwide.[8],[9]

SUI, a chronic and debilitating condition, is defined as an involuntary loss of urine during physical activities, such as sneezing, coughing, or laughing, and is usually associated with the pelvic floor muscle weakness. UUI is defined as an involuntary loss of urine, associated with a sudden need to urinate that is difficult to delay. MUI is characterized by a combination of SUI and UUI features.[3],[10] The different approaches to UI treatment include surgical, pharmacological, and noninvasive nonpharmacological methods, and medical therapy and surgery can be used to treat some patients. However, for many patients, these treatments are either ineffective or partially effective, and other management strategies, such as containment strategies, are needed.[11]

Evidence suggests that UI noninvasive management strategies are more acceptable to women.[12],[13],[14] Nevertheless, it is important to determine whether these noninvasive therapies are effective.[15] The current first-line treatment is the pelvic floor muscle training, which is used in combination with bladder training for SUI, while antimuscarinics are prescribed for UUI. Other alternatives, such as electrical stimulation, vaginal cones, and urethral inserts, are the second-line conservative treatment options for both SUI and UUI.[16]

For many years, the nontraditional, noninvasive management of female UI has involved extracorporeal electromagnetic innervation (ExMI). The ExMI creates a pulsed magnetic field and results in nerve depolarization in the pelvic floor, leading to pelvic floor muscle contraction. It is known that ExMI can uninterruptedly pass through clothes and penetrate into all body tissues without any alteration.[14],[17] Earlier studies reported this approach to be effective in reducing the frequency of incontinence and leakage episodes in women with both SUI[15] and overactive bladder,[13],[14],[18] which consequently caused an improvement in their QoL.[13],[14],[19] Besides, it has been shown that continuous electromagnetic stimulation affects urethral closure and bladder inhibition, elevates the urethral closure pressure, and increases bladder capacity.[20] However, later studies found significant therapeutic effects in those with a poor pelvic floor muscle tone at baseline and reported a very high UI recurrence rate.[21]

So far, studies have not comprehensively addressed electromagnetic stimulation use and effectiveness for UI treatment. None of the available therapies or surgical approaches have been completely effective for women who suffer from UI. Therefore, the present study aimed to evaluate the efficacy and safety of pulsed electromagnetic field (PEMF) stimulation as a new therapeutic approach for urinary symptoms in women with UUI, SUI, and MUI.


  Materials and Methods Top


This quasi-experimental study investigated the PEMF stimulation therapy effectiveness and safety in women with UI in a private UI treatment clinic in Rasht, Iran, with the inclusion criteria, i.e., age >21 years; ability to read and write; and a history of SUI, UUI, or MUI, and the exclusion criteria, i.e., having a pacemaker; cardiac arrhythmia; overflow UI; neurologic or psychological disorders; pregnancy; a history of surgery for UI treatment; a diagnosis of pelvic inflammatory disease; a history of surgery in the last 3 weeks or during 8 weeks of the study; a history of magnetic stimulation therapy; pelvic organ prolapse (POP); surgery for POP; pelvic or perineal trauma; neurogenic bladder; use of alpha-adrenergic antagonists, diuretics, or other medications intensifying UI; suspicion of bladder fistula; a urinary tract infection; hematuria; and residual urine more than 200 mL.

Women who complained of UI after a subjective examination, such as history-taking and physical examination, were divided into groups, based on the inclusion criterion of having one type of UI (SUI, UUI, and MUI). The Bristol Female Lower Urinary Tract Symptoms (BFLUTS) questionnaire was used in this study to evaluate UI severity, of which only one domain, including five questions related to UI, was used; the questions of four other domains were not relevant to the goals of this study.

Before the study, each participant signed a written informed consent form. The patients were treated for 6 weeks (two sessions per week), in which each treatment session took 20 min (two 10-min phases with a 5-min intermission). The treatment device was a NOVAmag NT-60 Magnetic Incontinence Therapy Chair (NOVAmedtek, Turkey). The patients were asked to sit on the chair during electromagnetic radiation delivery. Low-frequency pulses were used for UUI, high-frequency pulses for SUI, and a 10-min phase of low frequency and high frequency for MUI, with a stepwise pulse intensity increase regarding the patient's tolerability. At the end of each session, the patients were interviewed (face-to-face or phone interviews) for any complications, such as pain, burning, or discomfort in the genitalia or perineum and vaginal hemorrhage. Furthermore, the BFLUTS score was calculated again at 3 and 6 months after treatment. The treatment efficacy was defined to reduce the number of used pads to zero or one pad per day.

This study, registered in the Iranian Registry of Clinical Trials (http://www.irct.ir//; IRCT code: IRCT201710034582N7), was approved by the Ethics Committee of Guilan University of Medical Sciences, Guilan, Iran (IR.GUMS.REC.1395.138), and conducted according to the Declaration of Helsinki principles. Research involving personal data of human participants was performed in compliance with all legal and ethical requirements. This study was retrospective and all of the patients' personal information remained confidential. In addition, the principles of trusteeship were fully respected by the researchers.

To prepare a database and perform a descriptive analysis, SPSS version 21.0 for Windows (SPSS Inc., Chicago, IL, USA) was used. The treatment efficacy is expressed as frequency and percentage, and the BFLUTS scores are expressed as mean and standard deviation. Repeated measures analysis of variance (ANOVA) and Bonferroni's correction tests were also used to compare the BFLUTS scores at baseline and at 3 and 6 months after treatment. Besides, ANOVA, Tukey's post hoc test, Friedman test, and Wilcoxon signed-rank test were used to compare the scores regarding the UI type, and also, to compare UI's success rate and treatment, Chi-square test was used, and the significance level was set at P < 0.05.


  Results Top


This study analyzed the data of 90 women with UI, with a mean age of 58.5 ± 13.9 years (range: 21–97 years), whose demographic characteristics are summarized in [Table 1]. The majority of women with UI were in the age group of 50–70 years, and the mean body mass index of the participants was 27.8 ± 5.6 kg/m2. Of 90 patients, 61 (67.8%) had MUI, 22 (24.4%) had UUI, and 7 (7.8%) had SUI.
Table 1: Individual characteristics

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Changes in leakage severity were significant from baseline to 6 months after treatment, while the leakage episode frequency significantly reduced in the three groups from baseline to 6 months after treatment (P < 0.001). Overall, changes in leakage severity during physical activity (e.g., exercise, coughing, or sneezing) were significant from baseline to 6 months after treatment. The results show that leakage severity significantly decreased in the UUI group (P < 0.001), with mean changes of 2.86, 1.89, and 1.25 at baseline, 2 months' posttreatment, and 6 months' posttreatment, respectively. These changes were not significant in the SUI group (P = 0.386), while they were significant in the MUI group (P < 0.001). Also, in the MUI group, UI severity showed a descending trend from baseline to 3 and 6 months after treatment (mean changes of 2.79, 1.92, and 1.3, respectively). Overall, changes in leakage severity were significant from baseline to 6 months posttreatment, regardless of the type of UI (P < 0.001), and the mean change decreased from 2.75 to 1.92 and 1.33 at 3 and 6 months after treatment, respectively [Table 2].
Table 2: Comparisons of leakage by type of urinary incontinence

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Based on the results, leakage episode changes were significant from baseline to the end of the study in the UUI group (P < 0.001); the mean leakage episode frequency decreased from 2.82 to 2.05 and 1.14 at 3 and 6 months after treatment, respectively. Besides, changes decreased from baseline up to 6 months after treatment in the SUI (P = 0.004) and MUI groups. Overall, leakage episode changes significantly decreased from 2.7 at baseline to 1.19 at 6 months after treatment (P < 0.0001).

Based on the results, leakage during physical activity, such as coughing and sneezing, significantly decreased in the SUI group (P = 0.014), MUI group (P < 0.001), and the total population (P < 0.001). Since none of the UUI group cases had a similar problem, it was not possible to compare the changes. The majority of the participants had no leakage problems (with no obvious reason) and no urgent need to urinate; therefore, no comparisons were made between the groups. Only two patients in the MUI group experienced a problem once per week or less, which persisted for 3 and 6 months after treatment. Moreover, the mean BFLUTS score significantly decreased in the MUI group during the study. Overall, the mean BFLUTS score decreased from baseline (7.42 ± 2.03) to 3 (5.56 ± 2.37) and 6 months after treatment (3 ± 2.33) [Table 3].
Table 3: The changes of bristol female lower urinary tract symptoms score by the type of urinary incontinence in three groups

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As shown in [Table 4], no significant difference was found in the frequency of complications from baseline to the end of the study, based on the results of Cochran's Q test. Overall, the number of used pads significantly reduced from 4.18 ± 3 pads/day (median, 4.00) at baseline to 2.19 ± 2.39 pads/day (median, 1.00) and 2.03 ± 1.08 pads/day (median, 0.00) at 3 and 6 months after treatment, respectively (P < 0.001). Changes in all three groups showed a significant decreasing trend, and the number of used pads also significantly changed from baseline to 3 and 6 months after treatment, based on the results of Bonferroni's correction test for pairwise comparisons. Overall, the frequency of using ≤1 pad increased from 31.1% to 81.1% within 6 months, and changes in the number of used pads were significant in all of the groups. Based on the Bonferroni's correction test, the frequency of used pads significantly changed from baseline to 3 and 6 months after treatment (P < 0.001) [Table 5].
Table 4: Distribution of complication by the type of urinary incontinence

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Table 5: Comparison of frequency of used pads by the type of urinary incontinence

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  Discussion Top


UI, being one of the most common and chronic problems in women, can affect their mental health and QoL.[4],[22] The present study aimed to evaluate PEMF stimulation efficacy and safety as a new approach for urinary symptoms treatment in women with UUI, SUI, and MUI. The results indicated that leakage severity and frequency significantly changed from baseline to 6 months after treatment. Also, changes in leakage severity were significant during physical activity, like coughing and sneezing, from baseline to 6 months after treatment, whereas changes in urinary leakage for no obvious reason, without an urgent need to urinate, were not significant during the study.

Magnetic field stimulation (MFS) is a novel method for stimulating the nervous system noninvasively, which can activate deep neural structures through induced electric currents, without pain or discomfort; however, the applicability of this approach remains unclear. A meta-analysis in 2019 indicated that MFS treatment is an effective modality for UI patients. In general, PEMF therapy has become an alternative for UUI and/or SUI treatment. This approach's advantages are its completely noninvasive nature, excellent safety, and excellent tolerability. It is believed that the nerves are particularly sensitive to PEMF effects, which may also regulate the local blood flow and other factors. This type of stimulation activates efferent nerves and motor endplates of the pelvic floor muscles, thereby improving muscle strength and endurance. It may also affect the somatic nerve firing rate, which is responsible for the pelvic muscle and sphincter tone. PEMF therapy's other advantages include reduced pain and depression.[23]

The present results are in line with other electromagnetic and static MFS studies. It has been also used for treating other diseases, such as multiple sclerosis, Parkinson's disease, diabetic foot ulcer, and migraine. Although the use of this approach for UI treatment has not been reviewed, all available resources have reported remarkable results.[12],[13],[14],[20],[21] In this regard, in a study on 91 female patients with UI, a significant improvement was observed in the incontinence-QoL score, along with a decreased daily pad use after 16 sessions of perineal magnetic stimulation; however, there was a 63% failure rate for leakage treatment.[12] In another study, wherein 50 patients were treated with ExMI and were followed up for more than 3 months, the number of used pads significantly reduced, and the leak episodes per day significantly decreased.[14]

According to the results of the present study, no significant change was found in leakage severity in the SUI group, but a significant change was observed in the UUI and MUI groups over 6 months. It seems that the SUI group's failure to respond to treatment may improve by continuing the treatment because patients often have pelvic floor muscle injuries after multiple surgeries or deliveries, which do not simply heal. In other studies, patients with no prior UI surgery had the best results.[12]

Moreover, in a previous study, leakage intensity, measured by the pad weight, significantly reduced in 50 patients.[14] In the present study, the leakage episode frequency also reduced in all three groups. There was a significant reduction in the leakage episodes during coughing and laughing in the SUI and MUI groups, which is consistent with the finding of previous studies.[24] Besides, the present study's results showed that the mean BFLUTS score significantly reduced in the MUI group. Fujishiro et al. also reported that the bladder capacity significantly increased after treatment, and the QoL score significantly improved in the active stimulation group.[20]

Regarding disease severity, the patients can use the number of used pads as one of the criteria to understand the healing process. In general, the number of used pads changes depending on the leakage intensity. In this study, the mean number of used pads showed a significant descending trend from 4.18 ± 3 at baseline to 2.19 ± 2.39 at 3 months and 2.03 ± 1.08 at 6 months after treatment. Furthermore, the changes were significant within the groups. An important finding of this study was that changes from baseline to the 3rd month were insignificant, while there were significant changes from the 3rd to the 6th month and also from the baseline to the end of the study. In agreement with a previous study,[14] this finding suggests the lack of a short-term response to treatment; therefore, a long-term treatment is needed.

Some complications, such as pain, burning, and discomfort in the perineum, besides vaginal hemorrhage, have been reported in UI treatment. Nevertheless, none of the patients experienced severe complications, and since all side effects were minimal and tolerable by them, this treatment can be considered a painless approach.[12] Also, since no significant complication was observed in the patients, therefore, there were no significant changes in complications during the study. PEMF therapy is a temporary method, which cannot substitute a surgical treatment. However, it can be regarded as a conservative and noninvasive approach for SUI management in patients either ineligible for or unwilling to undergo surgery.[23]

The present study had some limitations, first being the lack of a control group as one of the main shortcomings of this study. Second, UI type was diagnosed based on a subjective assessment (i.e., history-taking and physical examination), and urodynamic testing was not performed for the patients. Finally, the short-term follow-ups were another limitation of this study. Therefore, to confirm the present results, blinded cross-over studies with long-term follow-ups are suggested.


  Conclusion Top


The PEMF stimulation approach may be effectively used to treat all three types of UI. The best response to treatment was obtained after at least 6 months. In the present study, a significant reduction was reported in the UI severity, the frequency of leakage episodes, and the number of used pads per day. Since previous studies reported this treatment's significant positive effects, besides its lower risk and patient acceptability compared to interventional methods, it may be applied more extensively for UI treatment in the future. Besides, this treatment's long-term outcomes remain unclear, and future studies are needed. Given its high patient acceptability, PEMF stimulation can be recommended as a safe, effective, and noninvasive approach, used along with routine treatments.

Availability of data and material

The data supporting the findings of this study are available from the corresponding author upon request.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5]



 

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