An Acupuncture Protocol for the Treatment of Erectile Dysfunction: A Delphi Process

Erectile dysfunction (ED) is probably one of the male health issues with the most rapidly increasing prevalence worldwide. It is estimated that about 322 million men worldwide will suffer from ED in 2025 [1]. One of the reasons for this is the fact that ED is not an isolated syndrome but mostly a symptom related to a wide variety of underlying diseases such as cardiovascular diseases. Generally, men suffering from ED have an increased risk of all-cause mortality [2]. Moreover, several pharmacological treatments such as alpha blockers, antihypertensives, antidepressants, antipsychotics, antiepileptics, antiandrogens, diuretics, and cancer treatments may induce ED as a side effect [3].

Over the last years, the symptomatic treatment with pharmacotherapy such as PDE5 inhibitors has become the first-line treatment for ED and has improved life for many men suffering from ED [3]. However, not all patients benefit from the use of PDE5 inhibitors; they are effective in only 60–70% of the patients [4]. Thus, for a substantial number of patients, pharmacological treatment options are not available. In addition, PDE5 inhibitors are not without side effects and can induce headache, flushing, gastric problems, nasal congestion, vision problems, dizziness, and priapism [4, 5]. In a recent publication, the authors discuss exactly these challenges related to the pharmacological treatment options for ED and call for “simpler, cheaper, and equi-effective” treatments with fewer side effects. Furthermore, they request a long-term causal-therapeutic intervention in addition to the date symptomatic treatment [6].

Acupuncture as a non-pharmacological treatment option for ED has not received more attention and is not intuitive because it has a long tradition [7] and is still applied, despite the availability of PDE5 inhibitors. To date, there are mainly two reasons why men suffering from ED turn to acupuncture: (i) they wish to avoid the common side effects of PDE5 inhibitors and (ii) they understand acupuncture as a non-pharmacological treatment option and thus a means to take control over their own health status [8].

Generally, acupuncture has the potential to regulate the autonomic nervous system, stimulate nerve endings, and activate various transmitters in the central nervous system [9, 10]. Transmitters such as dopamine, acetylcholine, NO, oxytocin, adrenocorticotropin have a promoting effect on erection [11]. Consequently, acupuncture stimulation has been shown to directly improve the blood supply of the corpus cavernosum, a pathway, which is likely to improve the firmness of the erection and the erectile function [12]. Thus, it is plausible to hypothesise that acupuncture treatment for ED may provide a combination of local as well as systemic stimulatory effects on erection.

A recent systematic review and meta-analysis confirms that acupuncture may provide a useful treatment option for ED. The analysis revealed that a combination of PDE5 inhibitors and acupuncture exhibits a better effect on erection than medication alone. Nonetheless, rigorous clinical studies with large sample sizes and objective measures are still warranted, and one of the reasons why it is still difficult to draw firm conclusions from existing studies is the fact that a best-practice treatment protocol for the acupuncture treatment of ED, which could serve as a basis for these studies, is not available [9].

Even though considerable progress has been made over the last decades in understanding the physiological mechanisms of action of acupuncture, the selection of the appropriate points for needling in a clinical setting is still usually based on the ancient system of traditional Chinese medicine (TCM). Even though in modern acupuncture philosophy the TCM system may be mainly understood as an educational approach in order to select treatment approaches, the system is still central in order to select the combination of acupuncture points used in clinical applications [13]. What makes the standardisation of acupuncture treatments even more complex is the fact that the concept of diagnosing a “syndrome” is central within this system in order to identify the appropriate treatment approach. In conclusion, due to educational and cultural differences in countries where acupuncture is practiced, it must be taken into account that clinical acupuncturists as well as acupuncture researchers may apply different traditions with regard to diagnosing TCM syndromes and accordingly influencing choice of acupuncture treatment [14, 15].

Despite the current diversity of treatment approaches, the recent meta-analysis concluded that acupuncture treatment for ED may provide a clinically effective add on intervention to pharmacological treatment. Nonetheless, the authors also conclude that more high-quality studies are needed. Possibly the most important precondition to improve the quality of research in this field and to make the studies comparable is the availability of a best-practice, standardised treatment protocol for the acupuncture treatment of ED.

In conclusion, there is currently no consensus or standard acupuncture protocol for the treatment of ED available [16]. However, if the quality of acupuncture clinical trials for the treatment of ED are to be improved beyond the standardised reporting of clinical trials (see, e.g., the STRICTA checklist) [15, 17], then at least a more semi-standardised treatment approach would be most useful. Such an expert opinion-based best-practice protocol will not only help to improve the quality of clinical trials but also will inform and improve clinical practice. Consequently, there is a need for a semi-standardised treatment protocol which includes recommendations on which points to use and which dosing would be optimal [18]. One of the best approaches to develop a best-practice acupuncture treatment for ED is to use a Delphi process to reach expert consensus [9]. Therefore, the aim of this study was to develop a best-practice acupuncture (TCM) treatment protocol by means of a Delphi process.

TCM treatment of ED usually includes acupuncture treatment as well as the use of herbal medicine. However, a very limited number of TCM herbs are approved and available from safe sources in Europe. Moreover, the legislation in Norway and many of the EU countries prohibits the use of Chinese herbal medicine. Therefore, only an acupuncture treatment setting which includes diet and lifestyle advice was investigated in the Delphi process study [19, 20].

The Delphi process aims to build consensus by using a series of questionnaires delivered using multiple iterations to collect real-world knowledge from a group of experts. The method has been widely used in concept framework development in medical research [21].

One central advantage is that the Delphi process provides anonymity to respondents and an opportunity to freely express opinions; moreover, it prevents individual dominance in the group [22]. Limitations concerning Delphi studies are that they are time-consuming, often have low response rates, and lack detailed information on how they are conducted, which results in low repeatability and limited external validity [21]. Currently, there are no guidelines or recommendations on the appropriate sample size for expert consensus in a Delphi process. However, it is established that a minimum sample size of 10 experts is adequate for content validity [22, 23].

The recruitment for participants to the Delphi process started on May 15 and ended on November 1, 2020. Thirty-four English-speaking national and international TCM acupuncturists were contacted through Messenger, e-mail, and telephone and invited to participate in the panel. The participants were found through personal network as well as through a snowballing approach [24]. The criteria used to identify potential participants included English-speaking practitioners with TCM training and a minimum of 5-year experience and previous experience (>5 patients) in treating male health issues. The aim was to ensure a widespread distribution of qualified participants from as many different Western countries as possible.

The primary data source in this modified Delphi process consisted of four rounds of questionnaires with open-ended and closed questions. The study built on the work of Smith et al. [25], where the items were modified to fit the subject of this Delphi process [26]. Permission to use the questionnaire was obtained by e-mail from the principal researcher Caroline Smith May 11, 2020. The first round in the Delphi survey commenced on August 14, 2020, and the fourth and final round concluded on June 6, 2021. Each round took 6–12 weeks. To improve the response rate, which often is low in Delphi processes [25], the principal researcher (M.L.D.) sent three reminders including one personalised response after each round to ensure an adequate response rate. The participants remained anonymous through the whole process to encourage freedom of expression [25].

The four steps of the Delphi process were as follows:

• round 1: identify the TCM syndromes relevant in an ED diagnosis

• round 2: reduce the list of syndromes and determine relevant symptoms and signs for the syndromes to make an accurate TCM diagnosis of ED

• round 3: investigate the syndromes that were rated as uncertain in round two

• ound 4: establish a best-practice scenario based on the result of the first three rounds and determine what constitutes good clinical practice for optimal results for this condition.

The data were analysed by descriptive statistical calculation by M.L.D. The data were entered into Excel and analysed for mean, median, and sum of appropriateness. The RAND appropriateness method was applied to quantitatively assess the importance for inclusion and the agreement of the panellist. In case of missing data, attempts were made to obtain information by contacting the participant.

The Norwegian Centre for Research Data AS has concluded that the processing of personal data in this project complies with the data protection regulations (June 3, 2020 [ref. No. 235359]).

Twelve participants from ten different countries signed the consent form and completed one or more rounds. The median/mean clinical experience of the subjects was 16–20 years. Demographic of the Delphi participants are shown in Table 1.

The initial list of TCM syndromes with symptoms and signs the panellist expected to see in men with ED is shown in Table 2. Thirty syndromes with an interrelated list of symptoms and signs were suggested by the 11 participants who responded within the timeframe.

Acupuncture treatment protocol parameters are shown in Table 3. The panellists indicated that a treatment protocol in a future clinical study should consist of semi-standardised components (some fixed treatment components and some individualised). The majority recommended a treatment frequency of once or twice a week and that de qi (needle sensation or response) should be obtained. An additional recommendation was to needle deep with strong de qi sensation directed towards the genitals. A majority suggested that regardless of syndrome, a combination of manual acupuncture and moxa (burning of dried leaves of the Artemisia vulgaris) will provide the best result.

Table 4 provides an overview of acupoints (as shown in Table 4). A list of 28 acupoints for ED found in the literature was presented to the panellist. There was a consensus of 17 acupoints, in addition the panellist-suggested 26 acupoints plus three point combinations.

There was consensus of the use of herbs as an essential co-intervention, and exercise and dietary therapy is prescribed by the majority. Kegels (exercises to strengthen pelvic floor muscles) and relationship therapy are also considered to be essential co-interventions in the treatment of ED. The panellists gave also advice on self-care which includes rest and relaxation, regular sleep, stress reduction, lifestyle changes, dietary advice, relationship therapy, and to refrain from ejaculation during treatment process.

Since ED is perceived as a taboo topic [27], the panellists were asked for recommendations and advice regarding the patient/practitioner relationship. The panellists emphasised the importance of building trust, to have a non-judgmental attitude, to be open minded, and to encourage the patient to speak freely. They also recommend asking straightforward questions and at the start of the conversation clarifying that they also will be asked a series of questions regarding sexual function. The therapist should emphasise that ED is a common disorder like any other disorders so that the patient has no reason to be ashamed. The recommendation was “simply to normalise the subject.”

Following analysis of the first round, a summary report based on the results from the first round was circulated to the participants, who were invited to participate in the second round. The participants were asked to rate the appropriateness of the suggested 30 TCM syndromes by choosing a number from 1 to 9, where 1 indicates that it is “highly inappropriate” and 9 indicates that it is “highly appropriate” [28]. Syndromes with median scores in the 1–3 range were classified as inappropriate and were not further investigated. Those in the 4–6 range were classified as uncertain and were investigated further in round 3. Those in the 7–9 range were rated as appropriate and were further investigated for determining symptoms and signs. There was a consensus on eight syndromes in the round 2. In addition, fourteen syndromes, combined syndromes, combination of syndromes, and imbalances in substances were rated in the 4–6 range as uncertain and taken forward for further development to round 3. The rated appropriateness of the 30 syndromes is shown in Table 5.

Newly nominated items from round 2 were presented. Of the 13 syndromes rated in this round, consensus was achieved on four (median score ≥7). The results of the rating of the TCM syndromes in round 3 are shown in Table 5.

The participants were asked to rate the appropriateness of a list of acupoints suggested in round 1, where 1 indicates that it was highly inappropriate and 9 indicates that it was highly appropriate for treating ED. Only those considered to be highly appropriate (7–9) were included in the final list (shown in Table 6). The final list of acupoints from rounds 1 and 3 is shown in Table 7.

The Delphi panellists were asked to rate to what extent they thought the syndromes determined in this Delphi process represent best-practice acupuncture for treating ED, where 1 indicated that it was highly inappropriate and 9 indicated that it was highly appropriate for treating ED. The median score was 8. The panellists were also asked to rate to what extent the consensus acupoints represented best-practice acupuncture for treating ED. The median was 6. Furthermore, they were asked to list three acupoints relevant for each syndrome from the consensus list of acupoints (shown in Table 8).

Finally, they were asked “to what extent do you think the results of this Delphi process could be used as a treatment protocol for later clinical study”? The median score was 7, which is considered appropriate without disagreement.

Twelve syndromes with symptoms and signs and 24 acupoints for the treatment of ED have been established for the use in a future clinical trial. The treatment protocol consists of semi-standardised components where additional acupoints (shown in Table 7) can be selected based on the patient’s syndrome and symptoms in addition to the main acupoints (shown in Table 8), with 11–15 treatments given in a treatment frequency of once or twice a week. Needling should be deep in direction towards the genitals, and strong de qi should be obtained (also towards the genitals). A combination of manual acupuncture and moxa is recommended regardless of syndrome. There are different opinions in the TCM literature related to the use of moxa for heat syndrome, e.g., yin xu and damp heat, in the literature [29, 30]. Herbs, Kegel exercises, relationship therapy, exercise, and dietary therapy are essential co-interventions in the treatment of ED. Self-care advice according to the TCM principle includes rest and relaxation, regular sleep, stress reduction, lifestyle changes, and to refrain from ejaculation during treatment.

In view of ED in the ancient system of TCM, there are some cardinal symptoms to some of the syndromes. For example, in Ki Yang Xu, the patient may suffer from lack of morning erection, low libido, and cold genitals in addition to cold, weak, sore back. The relevant acupoint in the protocol for Ki Yang xu syndrome is CV 4. Men presenting with symptoms such as achieving easy erection that does not last, excessive sex drive, and premature ejaculation will pertain to the syndrome Ki Yin Xu and according to the protocol should be treated with acupoints KI 6 and CV 4. In addition to the regular LR Qi stagnation symptoms, men with ED often present with a lack of desire, and the preferred acupoints are LR 3 and LR 5 based on the recommendations of the expert practitioners. In HT and GB Qi xu syndrome, HT 7 is the suggested acupoint in the protocol and the cardinal symptoms are fear of sex, reluctance to be involved in close relationships, and ED being worse with a partner than when alone. Genital itching and/or dampness are symptoms related to damp heat sinking to lower Jiao/damp heat in LR and KI, and the acupoint of choice is LR 5 (Fig. 1).

The Delphi process provided a protocol based on a consensus of recommendations of expert TCM practitioners. The protocol equips acupuncture practitioners with a toolbox of 12 syndromes with accompanying symptoms and signs that the acupuncture experts considered to be fundamental as best-practice acupuncture for treating ED. Furthermore, the protocol constitutes semi-standardised components and lists 24 acupoints relevant for the treatment of ED. The optimal dose sufficient to achieve “an erection adequate for sexual satisfaction” is 11–15 treatments given in a treatment frequency of once or twice per week. Moreover, this protocol contributes to establishing a best-practice treatment protocol for the use in future clinical trials and may thus contribute to standardization and comparability of future studies on ED.

Despite that an acupuncture-only protocol was explored and developed in this Delphi process, the experts recommend the use of herbs as an essential co-intervention, in addition to exercise and dietary therapy. Self-care advises such as rest and relaxation, regular sleep, stress reduction, Kegel exercises, lifestyle changes, relationship therapy, and to refrain from ejaculation during treatment process are considered essential for the result of the treatment. Lifestyle advice regarding ED is supported by medical research [31, 32]. Moreover, the experts suggested that a combination of manual acupuncture and moxibustion will provide the best result regardless of syndrome. Moxibustion is well known and commonly used intervention alone or in combination with acupuncture in the treatment of ED [5]. However, moxibustion techniques were not included in this first Delphi study on acupuncture and ED. Nonetheless, a standardised protocol is also needed for needle stimulation and moxibustion techniques. These issues could be further explored in a new Delphi study.

In general, clinical studies in the West have been conducted using significantly fewer number of treatments compared to Chinese trials, where a treatment course consists of daily treatment for 10 days and three or more treatment courses. According to the authors, for some conditions, 6 weeks of treatment is needed to obtain any clinical improvement and twice the time to achieve optimal effect of the treatment [14]. Clinical outcomes in acupuncture trials may be dose-dependent and influenced by the applied acupuncture protocol. [14, 16] The recommendation that 11–15 treatment will be sufficient to achieve “an erection adequate for sexual satisfaction” needs to be verified and validated in further clinical studies.

According to the TCM system, the literature kidney or liver syndromes of disharmony are often involved in ED [33]. Ten out of 12 syndromes in the protocol involve kidney and liver/gallbladder pathology. The list of syndromes in the protocol includes combinations of syndromes and imbalances in substances (Qi, Xue, Jinye, Jing, and Shen) not presented in the TCM literature. [33, 34]. Similar differences have been described between clinical acupuncturist and Delphi experts in a study on hot flashes based on TCM acupuncture treatment. This divergence may be due to the lack of a common ground and understanding of TCM syndromes, deriving from differences in education or in-depth knowledge and experience in addition to the subjective nature of syndrome differentiation – resulting in discrepancies in which symptoms comprise each syndrome [35]. According to the TCM literature, the interrater agreement on syndrome differentiation appears to be very low, and the diagnostic accuracy for differentiation of syndromes is not better than chance [36‒38]. Combined with the lack of international standards, attaining consensus in syndrome differencing is a challenging endeavour [38].

TCM and modern medicine share to some extent similarities in how models of illness and health are interrelated and diagnosis making builds upon assessing symptoms and signs from the patients in both medical systems, though the framework and language of physiology and pathophysiology differ widely. [13, 39] The TCM model of pathophysiology is complex and involves interrelated organs and systems [34]. Therefore, it may turn out that there are several different theories that still will lead to clinical valid results even if practitioners assess symptoms, syndromes, and diagnosis differently [40].

The finalised list of acupoints in the protocol has some deviations compared to the TCM literature. The acupoints ST 29, KI 11, LR 5, LR 8, and GV 1 have not been reported to be used in research literature for ED but were rated appropriate for the treatment protocol by the expert practitioners. ST 29 is a point frequently used in research for women with polycystic ovary syndrome [41]. KI 11, LR 5, LR 8, and GV 1 are local points for urogenital issues and may be relevant in the treatment of ED [42]. Nine of the points from published studies on ED presented in round 1 did not make it to the consensus list. None of them (CV 5, KI 1, KI 27, BL 15, 24, 54, LI 4, LI 11, SI 4) are referred to be used for ED in the available English TCM literature. Hence, this might reflect why there was no consensus on these points.

A recent study using data mining technology searching Chinese databases and PubMed found that the most frequently used acupoints for ED are CV 4, BL 23, SP 6, GV 4, ST 36, CV 3, BL 32, CV 6, KI 3, and LR 3 [43], which is in concordance with our protocol. The most common acupoint combinations for ED are BL 31, BL 33, BL 32, BL 34, SP 6, BL 23, and CV 4 [43]. ST36, LR3, SP6, and PC6 are the most frequently selected acupoints in clinical settings for a wide variety of conditions [44‒46]. The same acupoint may be used to treat many different diseases as individual acupoints have a wide variety of indications [44, 45].

Unlike in focus groups, participants in Delphi studies remain anonymous to each other, which reduces the effect of dominant participants influencing the outcome [25]. The expert groups are varied in composition representing acupuncture participants from ten different countries in three continents. However, all members of the panel live in the Western part of the world. Secondly, a comprehensive approach was chosen to identify items that might constitute an adequate acupuncture protocol for the treatment of ED in a clinical trial. Thirdly, different education emphasise male health to a varying degree. In opposite to Western medicine, male health has not received the same appreciation and popularity as women-related issues in clinic and research in the acupuncture profession. This is an initial attempt to gather information across the community of acupuncture. This study has the potential to motivate other researchers to investigate acupuncture treatment for ED in their own countries – hopefully contributing to further knowledge and development of a standardised treatment protocol.

This study has also limitations. Firstly, despite the careful selection of panel members and following the Delphi methodology rigorously, the results of this consensus may not cover the opinion of the entire acupuncture community. Secondly, the legislation in Norway and EU prohibits the use of Chinese herbal medicine; therefore, an acupuncture-only treatment setting was investigated in this study. Other limitations could relate to the participation of experts. The acupuncture training and experience of the experts have certainly influenced their responses to the Delphi rounds and the final protocol. The result reflects the opinions of the panellists. Another panel, e.g., with experts of an Asian origin, may come to different results. Another potential limitation is that the data analysis was performed by only one researcher.

ED is a health condition which affects all aspects of life, potentially with severe consequences for quality of life and well-being. For the relative high number of men (30–40%) where pharmacological treatment such as PDE-5 inhibitors is not an option, other treatment modalities are required. Acupuncture alone or in combination with PDE5 inhibitors could be a solution for this group. Acupuncture may be a long-term causal-therapeutic intervention, simple, and equi-effective with few side effects for the treatment of ED as requested [31].

Acupuncture is widely used in women-related issues, and a significantly larger proportion of acupuncturists offer treatment for gynaecological ailments. Further, there appears to be a larger proportion of acupuncture research related to women’s health [8]. Our concern is that male diseases have not received the same extent of attention within the acupuncture profession. The taboos surrounding of ED prevent many men from seeking help for this condition [27], as well as refrain acupuncture practitioners to treat this common ailment. However, in Chinese medicine, sexual health is seen as an important aspect of good quality of life and should be a part of the clinical interview [5]. The recommendation of the experts is to “simply to normalise the subject.” This protocol will hopefully inspire more practitioners to include male health issues, such as ED in their practice by having the tools for diagnosis and treatment in hand.

This study has developed a protocol for the use in clinical practice and clinical trials. Despite the challenges we faced, we see this as a first step towards an international consensus in Western societies in how to treat ED with acupuncture in TCM based clinical trials. However, further investigation and validation of syndromes, symptoms, and signs regarding ED is necessary. Although the experts gave the treatment protocol a high score, it has not yet been verified in a clinical trial that the outcome will result in “an erection adequate for sexual satisfaction.” Therefore, its clinical effectiveness needs to be demonstrated. Nonetheless, ED is an under-researched and possibly tabooed area in acupuncture research.

The results of the Delphi study introduce for the first time a consensus-based protocol for the acupuncture treatment of ED. Eleven acupuncture experts were able to reach consensus on 12 syndromes with symptoms and signs for the treatment of men with ED. The treatment protocol consists of semi-standardised components including 24 acupoints for treatment of ED. About 11–15 treatments given once or twice a week was considered to be an optimal dose sufficient to achieve “an erection adequate for sexual satisfaction.” Nonetheless, the results should be used with caution as large inconsistencies and discrepancies were discovered, and clinical effectiveness needs to further be elucidated.

We are grateful to the Delphi participants for their substantive engagement and feedback.

Consent to participate statement: Informed consent was obtained from participants to participate in the study; approved by NSD (Data Protection Services) number 235359, June 04, 2020.

The authors have no conflicts of interest to declare.

This study received no funding.

M.L.D.: conceptualization, methodology, data collection and analysis, project administration, writing – original draft preparation, and writing – reviewing and editing. T.A.: conceptualization, supervision, and writing – reviewing and editing. F.M.: conceptualization, supervision, and writing – reviewing and editing.

The data that support the findings of this study are available from the corresponding author upon reasonable request.