Review question
Is acupuncture a safe and effective treatment for treating overactive bladder in adults?
Background
Overactive bladder is the term used to describe a group of urinary symptoms, including an urgent need to pass urine, frequent voiding (emptying), urinary incontinence and waking one or more times at night to pass urine (nocturia). Sufferers may have one or more of these symptoms. Overactive bladder is a common complaint and can affect both men and women of any age, though it is more common in older people. Treatment can include bladder education, pelvic floor exercises, medication, botox injections into the bladder wall, sacral neuromodulation and surgery.
Acupuncture refers to the practice of inserting fine needles into defined points on the body in order to achieve an improvement in health. It is used in a wide range of conditions and has been suggested as a possible treatment for overactive bladder symptoms.
How up-to-date is this review?
This review includes all studies that met our eligibility criteria, published up to 14 May 2022. We are aware of six ongoing studies and two studies that we cannot obtain in full, which were not included in our review.
Study characteristics
We included 15 studies involving a total of 1395 participants with overactive bladder. The majority of the studies had small numbers of participants and we had some reservations about the study designs, processes or both in the majority of the studies.
Study funding sources
Of the 15 included studies, four were supported by Chinese Government-funded research grants and two were funded by Higher Education institutions. The open access publishing fee for one study was paid by the Norwegian Acupuncture Association. Eight studies did not report any source of funding.
Key results
The different methods used by the studies made the comparison of results difficult.
Compared to no treatment, the effect of acupuncture on curing or improving overactive bladder symptoms and the amount of minor side effects is very uncertain. No major adverse events took place. The were no reports on the effect of acupuncture compared to no treatment with regard to reducing urinary urgency, daytime urinary frequency, episodes of urinary incontinence or episodes of nocturia.
Compared to sham (fake) acupuncture, the effect of acupuncture on curing or improving overactive bladder symptoms is uncertain. Acupuncture probably makes little or no difference to the number of minor adverse events compared to sham acupuncture. No major adverse events took place in any of the studies. The evidence is very uncertain regarding the effect of acupuncture on the presence of absence of urinary urgency, daytime urinary frequency or episodes of nocturia. There is probably no difference between acupuncture and sham acupuncture in terms of episodes of urinary incontinence.
Acupuncture may result in a slight improvement in overactive bladder symptoms when compared with medication and may result in a reduced number of minor adverse events. No major adverse events took place. The effect of acupuncture compared to medication is very uncertain with regard to urinary urgency and episodes of incontinence. Acupuncture may have the same effect as medication on urinary frequency and may slightly reduce episodes of nocturia.
Certainty of the evidence
The majority of the evidence in this review is of very low or low certainty because the included studies had flaws in their design and/or execution. Many had small numbers of participants and were conducted over a short period of time. Given these issues, it is difficult to draw conclusions regarding how effective acupuncture is for treating overactive bladder. Further well-designed, large-scale studies are required to answer this question.
The evidence is very uncertain about the effect acupuncture has on cure or improvement of overactive bladder symptoms compared to no treatment. It is uncertain if there is any difference between acupuncture and sham acupuncture in cure or improvement of overactive bladder symptoms. This review provides low-certainty evidence that acupuncture may result in a slight increase in cure or improvement of overactive bladder symptoms when compared with medication and may reduce the incidence of minor adverse events.
These conclusions must remain tentative until the completion of larger, higher‐quality studies that use relevant, comparable outcomes. Timing and frequency of treatment, point selection, application and long-term follow-up are other areas relevant for research.
Overactive bladder is a common, long-term symptom complex, which includes frequency of micturition, urgency with or without associated incontinence and nocturia. Around 11% of the population have symptoms, with this figure increasing with age. Symptoms can be linked to social anxiety and adaptive behavioural change. The cost of treating overactive bladder is considerable, with current treatments varying in effectiveness and being associated with side effects. Acupuncture has been suggested as an alternative treatment.
To assess the effects of acupuncture for treating overactive bladder in adults, and to summarise the principal findings of relevant economic evaluations.
We searched the Cochrane Incontinence Specialised Register, which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (including In-Process, Epub Ahead of Print, Daily), ClinicalTrials.gov and WHO ICTRP (searched 14 May 2022). We also searched the Allied and Complementary Medicine database (AMED) and bibliographic databases where knowledge of the Chinese language was necessary: China National Knowledge Infrastructure (CNKI); Chinese Science and Technology Periodical Database (VIP) and WANFANG (China Online Journals), as well as the reference lists of relevant articles.
We included randomised controlled trials (RCTs), quasi-RCTs and cross-over RCTs assessing the effects of acupuncture for treating overactive bladder in adults.
Four review authors formed pairs to assess study eligibility and extract data. Both pairs used Covidence software to perform screening and data extraction. We assessed risk of bias using Cochrane's risk of bias tool and assessed heterogeneity using the Chi2 testand I2 statistic generated within the meta-analyses. We used a fixed-effect model within the meta-analyses unless there was a moderate or high level of heterogeneity, where we employed a random-effects model. We used the GRADE approach to assess the certainty of evidence.
We included 15 studies involving 1395 participants in this review (14 RCTs and one quasi-RCT). All included studies raised some concerns regarding risk of bias. Blinding of participants to treatment group was only achieved in 20% of studies, we considered blinding of outcome assessors and allocation concealment to be low risk in only 25% of the studies, and random sequence generation to be either unclear or high risk in more than 50% of the studies.
Acupuncture versus no treatment
One study compared acupuncture to no treatment. The evidence is very uncertain regarding the effect of acupuncture compared to no treatment in curing or improving overactive bladder symptoms and on the number of minor adverse events (both very low-certainty evidence). The study report explicitly stated that no major adverse events occurred. The study did not report on the presence or absence of urinary urgency, episodes of urinary incontinence, daytime urinary frequency or episodes of nocturia.
Acupuncture versus sham acupuncture
Five studies compared acupuncture with sham acupuncture. The evidence is very uncertain about the effect of acupuncture on curing or improving overactive bladder symptoms compared to sham acupuncture (standardised mean difference (SMD) -0.36, 95% confidence interval (CI) -1.03 to 0.31; 3 studies; 151 participants; I2 = 65%; very low-certainty evidence). All five studies explicitly stated that there were no major adverse events observed during the study. Moderate-certainty evidence suggests that acupuncture probably makes no difference to the incidence of minor adverse events compared to sham acupuncture (risk ratio (RR) 1.28, 95% CI 0.30 to 5.36; 4 studies; 222 participants; I² = 0%). Only one small study reported data for the presence or absence of urgency and for episodes of nocturia. The evidence is of very low certainty for both of these outcomes and in both cases the lower confidence interval is implausible. Moderate-certainty evidence suggests there is probably little or no difference in episodes of urinary incontinence between acupuncture and sham acupuncture (mean difference (MD) 0.55, 95% CI -1.51 to 2.60; 2 studies; 121 participants; I2 = 57%). Two studies recorded data regarding daytime urinary frequency but we could not combine them in a meta-analysis due to differences in methodologies (very low-certainty evidence).
Acupuncture versus medication
Eleven studies compared acupuncture with medication. Low-certainty evidence suggests that acupuncture may slightly increase how many people's overactive bladder symptoms are cured or improved compared to medication (RR 1.25, 95% CI 1.10 to 1.43; 5 studies; 258 participants; I2 = 19%). Low-certainty evidence suggests that acupuncture may reduce the incidence of minor adverse events when compared to medication (RR 0.34, 95% CI 0.26 to 0.45; 8 studies; 1004 participants; I² = 51%). The evidence is uncertain regarding the effect of acupuncture on the presence or absence of urinary urgency (MD -0.40, 95% CI -0.56 to -0.24; 2 studies; 80 participants; I2 = 0%; very low-certainty evidence) and episodes of urinary incontinence (MD -0.33, 95% CI -2.75 to 2.09; 1 study; 20 participants; very low-certainty evidence) compared to medication. Low-certainty evidence suggests there may be little to no effect of acupuncture compared to medication in terms of daytime urinary frequency (MD 0.73, 95% CI -0.39 to 1.85; 4 studies; 360 participants; I2 = 28%). Acupuncture may slightly reduce the number of nocturia episodes compared to medication (MD -0.50, 95% CI -0.65 to -0.36; 2 studies; 80 participants; I2 = 0%, low-certainty evidence).
There were no incidences of major adverse events in any of the included studies. However, major adverse events are rare in acupuncture trials and the numbers included in this review may be insufficient to detect these events.