Mind-Body Interventions as Alternative and Complementary Therapies for Psoriasis: A Systematic Review of the English Literature

Objective: Conventional therapeutic methods for psoriasis include topical and systemic drugs, phototherapy, and biologic agents. Despite the fact that these treatment methods, and especially biologic agents, are met with a considerable reduction in disease activity, they can sometimes be costly and are nonetheless accompanied by high risks of adverse events, ranging from mild to debilitating. Therefore, complementary and alternative medicine (CAM), especially mind-and-body interventions, such as acupuncture, psychotherapy, climatotherapy, and cupping may provide a cheaper and potentially beneficial outcome for these patients. Methods: We performed a systematic review of articles pertaining to acupuncture, cupping, psychotherapy and meditation, as well climatotherapy and balneotherapy in the management of psoriasis, by using the PubMED, Medline and Google Academic research databases and reference cross-checking. Results: 12 articles on acupuncture, 9 on dry or wet cupping, 27 concerning meditation, hypnosis or psychotherapy, and 34 regarding climate therapy or balneotherapy were found. Discussion and Conclusions: Currently, there is a lack of evidence in the English literature to support acupuncture as an effective alternative therapy for psoriasis, whereas cupping has been described in the majority of instances to result in Koebner phenomenon and clinical worsening. Stress management therapies such as psychotherapy, hypnosis, and meditation have shown promising results as complementary treatment methods. Climatotherapy and balneotherapy have already been proven as effective means of achieving clinical improvement in psoriasis. Further research is still needed to verify the usefulness of the lesser studied treatment methods.


Introduction
Psoriasis is a chronic inflammatory disorder that possesses decisive immunological and genetic elements, upon which several environmental factors may act, triggering the pathological cascade. Although it initially involves the skin, psoriasis leads to a substantial systemic impact, as well as a heavy psychological burden in many cases [1]. According to current data, it affects approximately 1-3% of the world population, presenting a first incidence peak between 15 and 20 years of age, followed by a secondary peak at 55 to 60 years [2]. In order to evaluate disease severity, various scores, such as the PASI (Psoriasis Area and Severity Index), or PGA × BSA (Physician Global Assessment and Body Surface Area) have been implemented, whereas the quality of life can be evaluated by the DLQI (Dermatology Life Quality Index) [3][4][5]. Presently, the PASI score is utilized for both the initial clinical evaluation of patients, and for their response to therapy. Although, was reduced to 36,15,38, and 42 for each respective category. Full-text screening led to the removal of a further 24 acupuncture articles, which were animal studies, protocols for systematic reviews and prospective studies, systematic and non-systematic reviews, aside from articles written in Chinese or Korean that only had the abstract in English. Six cupping therapy articles which were written in Chinese and were reviews or opinions were also excluded. Review articles on psychotherapy, meditation and hypnosis, as well as studies on different dermatological diseases concerning these treatment methods or studies simply evaluating stress levels for psoriasis patients without any interventions were removed, these being 11 in number. Finally, eight articles on climate therapy, that addressed other dermatological ailments, were both systematic reviews or otherwise, or that simply evaluated epidemiological tendencies without outcomes, were discarded. The flowchart in Figure 1 summarizes the study inclusion/elimination process for each of the four treatment methods. Regarding the articles on acupuncture and its analogous therapies, three were randomized controlled trials (RCTs), two were retrospective reports on non-randomized patients, one was a prospective observational report, and six were case reports of either one (four articles) or two (one article) patients. Excluding two articles, of which one was a prospective cohort of patients with various dermatoses, including psoriasis undergoing wet cupping [14], and the other a retrospective report of individuals who reported with secondary lesions after cupping [15], the remaining seven articles we obtained on cupping therapy were single-patient case reports. Fifteen articles on stress-reducing interventions were RCTs (one of which opted for a patient-preference randomization [16]); one was a nonrandomized prospective trial, and one was a prospective cohort, whereas the remaining ten were case reports. As for climatotherapy and balneotherapy, we identified 6 prospective RCTs and 7 non-randomized trials, 12 single-arm prospective studies, and 7 retrospective studies (out of which 3 were comparative), one open, uncontrolled prospective trial [17], and one multicenter controlled cross-sectional study [18].

Patient Populations
In total, we identified 429 patients experiencing acupuncture for psoriasis; 254 males and 175 females. The average age was 42.43 years, the oldest patient recorded was 84 years, and the youngest was only 9 years [19,20]. The treatment periods lasted from 1 to 14 months, while the disease itself had a variable duration, from 4 to 20 years. A summary of patient characteristics can be viewed in Table 1.
Within the studies included, all 31 psoriasis patients treated via cupping were male. Ages ranged from 17 to 67 years, with an average of 36.14 years based on the ages provided. Duration of symptoms ranged from as little as 2 weeks to 10 years, while cupping treatment length varied from 5 days to up to 3 weeks. Table 2 presents a brief description of collected patients undergoing cupping therapy for psoriasis.
Adding together all the patients undergoing stress management therapies and psychological support, we obtained a total of 1085 individuals, of which 492 were female and 455 were male, based on the data provided. Patient age averaged at 43.78 years. Disease length at the time of treatment initiation had the largest range of all procedures analyzed, from the very day of symptom onset [21] to 64 years [16]. Duration of treatment also varied widely, from 6 weeks to as long as 4 years, depending on the exact procedure. More elaborate patient population details are presented in Table 3.
A total of 8498 patients suffering from psoriasis were enrolled in the studies of climate therapy and balneotherapy (9236 including control patients without psoriasis), and according to available and specified data, these numbers included 4702 males and 3675 females. The average age of patients undergoing these therapies across all studies was 48.02 years. Although no data was obtained regarding length of the disease, they varied from one to 60 years, the most common values being centered around 20-30 years. Treatment length was most commonly 3-4 weeks, although some balneotherapy interventions took 6 or 8 weeks [22][23][24], whereas some patients under climatotherapy followed this treatment for as little as 6 days [25]. It is worth mentioning that the study of Langeland and that by Wahl employed the same patient population based on their characteristics [26,27]. As such, this population was only considered once when performing calculations. Table 4 depicts the patient populations that have experienced balneotherapy and climate therapy.                 Compared with the control group, there was a significant improvement in PASI score and fewer psoriasis recurrences in the therapy group, aside from a marked reduction in the topical use of cortisone and nonsteroid drugs. * Denotes the same patient population between the two studies, as indicated by the number of individuals recruited, gender distribution, mean age, the duration of the treatment program, and average length of disease [26,27]. Abbreviations (in alphabetical order): BCC, basal cell carcinoma; BMI, body-mass index; BPSS, Beer Shiva psoriasis severity score; BSA, body surface area; BPT, balneophototherapy; C, control; CRP, C reactive protein; CTG, consolidated therapy group; DLQI, dermatology life quality index; DSC, Dead Sea climatotherapy; enk, enkephalin; EQ-5D-3L, EuroQol−5 Dimensions−3 Levels (EQ-5D-3L); F, female; GHQ-12, 12-item General Health Questionnaire; GSW, geothermal spring water balneotherapy; H, healthy controls; 5-IGA, 5-point Investigator's Global Assessment; IT-GSW, intensive geothermal spring water balneotherapy M, male; MED, minimal erythema dose; mo, months; MTX, methotrexate; N/A, not applicable; NAPPA, Nail Assessment in Psoriasis and Psoriatic Arthritis; NAPSI, Nail Psoriasis Severity Index; nm, nanometers; NMSC, non-melanoma skin cancer; NS, not specified; P, psoriasis; PASI, psoriasis area and severity index; PGA, physician global assessment; PUVA, photochemotherapy; QoL, quality of life; QoL VAS, quality of life visual analog scale; RCT, randomized controlled trial; RIA, radioimmunoassay; SAPASI, self-assessed PASI; SAS, self-rating anxiety scale; sCD25, circulating soluble interleukin 2 receptor; SDS, self-rating depression scale; SF-36, 36-item Short Form of the Medical Outcomes Study questionnaire; STAI, State-Trait Anxiety Inventory; T1, Therapy 1; T2, Therapy 2; UTG, unconsolidated therapy group; UV, ultraviolet; UVA, type A ultraviolet; UVB, type B ultraviolet; vs., versus w, weeks; w/o, without; y, years.

Acupuncture
Acupuncture is a well-known Traditional Chinese Medicine (TCM) practice that has been successfully utilized for more than three millennia. It is generally considered a safe approach, with few side-effects, being accepted across the world for numerous ailments [96]. The exact origin of acupuncture is unknown, and a few styles have been defined, for example needling, moxibustion, cupping and acupressure. It is important to note that acupuncture is customarily used in combination with other therapeutic approaches of TCM, such as herbal remedies. In needling for psoriasis, there are several acupuncture points available in which, as the name implies, disposable needles are inserted into the skin to stimulate blood flow and reduce local inflammation though an as-of-yet imprecise mechanism [97]. A recent study performed on mice discovered that electroacupuncture, needling and fire needling was correlated with a lower local CD3+ T-cell population, as well as lower levels of substance P, neurokinin A, IL-17A, IL-1B, and IL-23p40 [96]. Acupoint stimulation should be implemented for a period of at least of six weeks in order to achieve therapeutic effect [98,99]. Some authors have reported a decreased recurrence rate of plaque psoriasis after acupuncture when compared to conventional medicine [96]. Still, not all authors agree on the efficacy of acupuncture, as data are scarce and, at least until recently, not always easily accessible to the researching community [98]. A recent meta-analysis on the use of acupuncture in psoriasis comprising 13 RCTs and a total of 1060 participants has shown that acupoint stimulation had a superior effect to the placebo (non-acupoint stimulation) [99]. However, the trials included in this meta-analysis clashed regarding the specific acupoints used, the exact number of stimulated points, as well as duration of acupuncture sessions. Furthermore, adequate blinding was realized in only two of the studies, thus making a proper comparison difficult. Nevertheless, according to the findings of these analyses, the acupuncture appears to provide benefits in the treatment of psoriasis irrespective of the stage of the disease, although it is challenging to ascertain the most advantageous technique [12,100].
Two RCTs did not show a significant improvement in PASI score when compared to a control procedure, either sham acupuncture [28], or oral Huoxue Jiedu Decoction and Vaseline cream alone [29], although the latter did demonstrate an amelioration in the quality of life. A third RCT revealed a significant improvement in PASI within both the treatment with auricular therapy plus optimized Yinxieling formula and control groups, yet more so in the former, whereas DLQI scores presented a non-significant decrease in these groups [30]. According to Jorge et al., ear acupuncture managed to result in the complete disappearance of psoriasis in five of their seven patients, while the remaining two presented marked recovery [31]. A retrospective study on 61 patients demonstrated moderate improvement in psoriasis patients, on average [19], while another such account of 80 patients observed a 91.3% treatment effectiveness, with 41 cured, 18 markedly improved, and 14 individuals improved [20]. However, no standard evaluation score was provided for accurate comparison. We identified four case reports totaling five patients that benefitted from clinical improvement after acupuncture [32][33][34][35], one even demonstrating the complete disappearance of lesions [32]. Two of these reports did not provide a severity score, and as such a more objective evaluation could not be performed [34,35]. There were also two case reports of patients presenting with Koebner phenomenon after acupuncture [36,37]. The Koebner phenomenon, as defined by the German dermatologist Heinrich Koebner (1838-1904), denotes the manifestation of isomorphic lesions at the sites of a cutaneous injury in an otherwise healthy skin [38,101]. It can occur in several dermatological afflictions, most commonly psoriasis, lichen planus, and vitiligo. Therefore, it is likely that interventions that involve damaging the dermis, such as acupuncture and cupping, may trigger this type of lesion in psoriatic patients.
Despite our rigorous search in this field of CAM, reference cross-check did not yield several of the cited articles. As such, we could not discuss some of the studies included in other reviews and meta-analyses. Regarding the use of acupuncture and its associated procedures, the majority of reports show a positive effect on the amelioration of psoriatic plaques. Several articles written in Chinese and not readily accessible to Western readers may provide further insight into the benefits of acupuncture in psoriasis. As of the writing of this review, a number of trials on the benefits of various acupuncture techniques in psoriasis are currently ongoing [97,102]. The reason for including acupuncture in our review of CAM methods for this disease is primarily because of its popular use in China and other Eastern countries.

Cupping Therapy
Cupping therapy is an ancient treatment method likened to acupuncture, also employed for various diseases. It has been described since antiquity, from the ancient Egyptians to the Chinese Han Dynasty, also being used in the times of Hippocrates and even to the early Islamic period [103][104][105]. Two types of cupping methods exist, namely dry and wet, also known as Hijama (or Hijamah) in Egypt and Arabic countries [39][40][41][42][43][44]106]. This treatment method creates a vacuum by placing glass suction cups directly on the skin of various body parts, mostly on the back, shoulders, buttocks or limbs [15,106]. The difference between dry and wet cupping stands in that the latter requires a skin incision either before or after performing the suctioning itself. Thus, it is believed that impurities in the blood and tissues can be drawn out, instead of simply transferred from one body site to another. The moving cupping method is a unique dry type of cupping that involves the application of lubricant (such as Vaseline) either to the treated body part or to the mouth of the glass cup and adsorbing the cup to the desired area. The physician then moves the glass cup manually across the skin in all directions while applying light force, thus producing flushing, heightened tissue blood flow, and in some cases even ecchymosis in the chosen treatment area [103]. This causes a local accumulation of antioxidant and anti-inflammatory products such as heme-oxigenase-1, carbon monoxide, biliverdin, and bilirubin, which also have antiproliferative and neruomodulatory effects [104]. Additionally, it was shown that cupping induces vascular endothelial growth factor (VEGF)-A expression in keratinocytes via the nitric oxide (NO)-mediated activation of hypoxia inducible factor (HIF)-1, thereby promoting angiogenesis [105]. It is thought that this method has the ability to increase skin tolerance and significantly improve its barrier function [104,105] and has already proven effective in the management of pain-related diseases, such as chronic low back pain or osteoarthritis [103]. A multicenter RCT trial is currently underway in China, aiming to determine the efficacy of moving cupping in the treatment of plaque psoriasis [103].
However, current evidence in the English literature is far from encouraging. The study of El-Domyati et al., which enrolled 50 patients with various dermatoses, including eight with psoriasis vulgaris, failed to show any improvement in psoriatic patients [14]. Moreover, three of these patients demonstrated Koebner phenomenon at the site of cupping, leading to the termination of therapy. Contrarily, all individuals with chronic idiopathic urticaria, 10 out of 11 of acne vulgaris patients (90.9%), and two out of nine with atopic dermatitis (22.2%), showed clinical improvement, whereas none of the patients with vitiligo presented any changes. In the report by Sharquie et al., 24 patients presented with on-site Koebner phenomenon after undergoing cupping, 16 (66.7%) of whom had been previously diagnosed with psoriasis [15]. Six other case reports demonstrated the Koebner phenomenon strictly on the regions receiving cupping therapy [40][41][42][43][44], and to the best of our knowledge, only the patient described by Malik et al. benefited from a reduction in disease severity after wet cupping [39]. Interestingly, only male patients were included in these reports, yet no explanation could be given for this reason. While we are aware that the Chinese literature holds several studies pertaining to the beneficial effects of cupping in psoriasis [107], these were either inaccessible to us or did not have an English full-text version. Thus, as it stands, there is little evidence in the Western literature to support cupping therapy as an effective or beneficial CAM management in psoriasis.

Psychotherapy, Stress Management and Meditation
Psoriasis is known to cause significant psychological distress, depression, feelings of stigmatization, and reduced health-related quality of life [108]. Moreover, stress has been recognized as a trigger factor in both the appearance and exacerbation of psoriasis, aggravating the cutaneous manifestations of the disease in more than half of the patients. Psychotherapy has been studied in several trials and individual case reports, with the results being promising [45][46][47], even as early as one millennium ago [48], but sometimes with little difference from the control groups receiving usual care or no treatment at all [16,49,50]. As of yet, the mechanism through which stress initiates or worsens this disease is unclear; however, some studies have shown marked improvement in the clinical state after psychotherapy. An RCT comparing phototherapy with and without listening to mindfulness-based stress reduction recordings during treatment sessions revealed that clinical improvement was achieved markedly faster in the meditation group [51]. The beneficial effects of hypnosis in psoriasis were evaluated in several case reports [52][53][54], as well as an RCT of 11 patients, which suggested that easily hypnotizable patients showed greater improvements in disease control [55]. Guided imagery, meditation, and cognitivebehavioral stress management was shown to offer moderate but statistically significant improvement when PASI, total sign score (TSS), and Doppler blood flow to psoriatic plaques were assessed [50]. Although the same trial did not yield a significant difference in PASI scores between the treatment group and the control group that did not receive any form of therapy. Meditation with or without imagery produced a marked clinical amelioration compared to no therapy at all, yet the mentioned study was limited by the small number of patients included [56]. The same effect can be observed when assessing Medical Resonance Therapy Music with standard care against standard care alone, although no statistical significance was specified [57].
In one prospective RCT of 40 patients, written emotional disclosure combined with UVB therapy led to a better clinical result and a longer period of time than the standard UVB treatment [58]. Nonetheless, two other RCTs on written emotional disclosure did show improvement in both treatment and control groups with control writing intervention (focusing on activities of the previous day) [59] and educational intervention, respectively [60], yet no significant difference between treatment and control groups was observed. Mindfulness-based cognitive therapy MBCT and its variants, mindfulnessbased self-compassion therapy (MBSCT), and self-help MBSCT (MBSCT-SH), have yielded positive results, though mixed in comparison with treatment as usual [61,62]. Similarly, internet-based cognitive behavioral therapy (ICBT) managed to improve physical functioning and diminish the impact of psoriasis on everyday activities in patients presenting a psychological risk profile, and also enhanced and maintained psychological wellbeing [63,64]. Based on the RCT by Bundy et al., a web-based online electronic Targeted Intervention for Psoriasis (eTIPs), also a form of cognitive-behavioral therapy, did not achieve a significantly different result when compared to standard care, yet, as the authors mentioned, the results were constrained by a large quantum of missing data [65]. Support group therapy may have the benefit of both clinical improvement and enhancing the patients' knowledge and ability to cope with the disease [21,66]. As stated by Piaserico et al., biofeedback and cognitive-behavioral therapy and UVB therapy resulted in a significant reduction in psoriasis severity, as quantified by PASI, in addition to a higher percentage of patients achieving PASI 75 response at 8 weeks in comparison to patients receiving only UVB therapy [67]. Thermal biofeedback led to the complete disappearance of all previously existing psoriasis lesions, as well as the disappearance without scarring of any new ones occurring during treatment in one reported case [68]. In another similar description, thermal biofeedback in conjunction with supportive psychotherapy managed to markedly ameliorate dermatological signs [69]. Although promising, these studies are few in number, are small in size, and some of them are steadily becoming outdated. Furthermore, despite no obvious risk tied to meditation or hypnotherapy, some argue that there is little evidence to support them as financially justifiable treatment methods [109]. Nevertheless, this may prove an advantageous complementary treatment method of psoriasis in the future.
Considering that psoriasis is stress-mediated, it stands to reason that psychotherapy and interventions that focus on stress reduction might be beneficial for these patients. The results of the majority of studies are promising; however, not conclusive. The remarkable variation in therapy length may be due to the heterogeneity of therapies included in this group, as well as individual characteristics and requirements of each patient. It is important to notice that these therapies are mostly used in conjunction with treatment as usual and should not be viewed as a replacement to standard care.

Balneotherapy and Climatotherapy
Balneotherapy and Climatotherapy denote already established CAM treatment methods in moderate-to-severe psoriasis, having been proven effective in the short-term clearing and remission induction across several studies [18,70,110,111]. The most common destination for climate therapy is the Dead Sea, with 18 out of the total of 34 studies included having been conducted there [17,18,25,[70][71][72][73][74][75][76][77][78][79][80][81][82][83][84]. This treatment method implies spending several weeks at the Dead Sea, bathing in its waters and lying in the sun. The Dead Sea is located on the lowest point on the landmasses of Earth, at approximately 400 m below sea level, possessing the highest concentration of salt of any natural body of water. It boasts exceptional climatic properties, which are beneficial for a wide variety dermatological conditions, specifically for psoriasis. The efficacy of Dead Sea climatotherapy is probably the result of a mixture between the anti-inflammatory effects of stress reduction, the antiproliferative and keratolytic effects of local minerals, and the particular UV characteristics at that latitude [18,70,110,111]. More precisely, UVA and longer wavelength beneficial UVB rays are found at the site of the Dead Sea, whereas shorter erythrogenic UVB rays are generally filtered [11]. Severe adverse events following this type of therapy are rare. According to David et al., climatotherapy at the Dead Sea for psoriasis patients was more frequently associated with elastosis, solar lentigines, poikiloderma, and facial wrinkles than in control patients, also displaying an exposure-dependent response [18]. Additionally, the same study concluded that Dead Sea climate therapy was not correlated with a heightened risk of developing melanoma or nonmelanoma skin cancer in these patients. Another retrospective study concluded that some of these patients present an increase in epidermal pigmentation when compared to pretreatment biopsy specimens, although there were no epidermal dystrophies or melanocytic atypia reported [83]. Contrariwise, consistent with the findings by Frentz et al., the overall risk of skin malignancies (especially non-melanoma skin cancer) in patients undergoing this therapy was higher than estimated for the general population [75]. The body surface distribution of cutaneous cancers favored multiple sites, and typically affected younger individuals, especially women. Reoccurrence of psoriatic lesions at previous sites can occur after a given period of time following Dead Sea climate therapy [73].
Several prospective cohorts demonstrated a significant decrease in PASI scores in patients following Dead Sea climatotherapy, the majority of individuals achieving a PASI 75 response or more [25,70,72,74,77,79,84]. Furthermore, some of these studies also showed an improved quality of life, as measured by DLQI [72,84]. Both Kushelevski and Harari reported a higher clearance rate of lesions in patients with early-onset psoriasis and those with a longer duration of the disease [76][77][78]81]. Currently, the influence of the number of previous climate therapy stays on clinical amelioration has not been definitively established [78,84]. Another ambiguity is the daily exposure to sun needed to effectively treat psoriasis, on one hand Even-Paz et al. stating that 3 h divided in two equal sessions from 9 AM and 2 PM were sufficient when compared to 4.5 and 6 h per day [74], and on the other, Harari and Shani reporting that the best results were obtained in patients staying in the sun at least 7 h daily [74]. Patients additionally receiving systemic therapies such as methotrexate might not demonstrate better results than those undergoing climate therapy alone [71].
Other locations that have climatotherapeutic or balneotherapeutic (bathing in hot springs) effects are in the Black Sea, Nord Sea, Baltic Sea, Canary Islands, Kangal Hot Springs in Turkey, or the Blue Lagoon in Iceland, but the evidence regarding each of these sites is lacking when compared to the Dead Sea [11,18,70,110,111]. Balneotherapy alone or in combination with standard treatment or phototherapy has repeatedly proven to be more effective than standard treatment alone [23,[85][86][87][88][89]. Geothermal sea water balneotherapy and narrowband UVB (NB-UVB) light therapy is apparently more effective in attaining clinical and histological amelioration, results in longer remission time and allows for lower UV doses than NB-UVB therapy alone [21]. Gran Canaria climate therapy has also shown potential in decreasing psoriasis severity, as well as promoting mental health and improving health-related emotional distress [25,26,90]. Balneotherapy in the selenium-rich waters of La Roche-Posay also has the potential of reducing severity [91,92]. Moreover, as concluded in the study of skin microbiome composition in these patients, the Xanthomonadaceae family associated with Proteobacteria phylum, and recognized as keratolytic, was linked to clinical amelioration after a 3-week balneotherapy treatment [91].
Consolidated balneotherapy supplemented with Chinese herbal medicine led to a notably longer remission time than the unconsolidated form, which was stopped after PASI dropped to 1.8-2.0 [93]. Leopoldine spa water balneotherapy showed a marked and statistically significant improvement when compared to double-distilled tap water treatment on the opposite arms of the same patients [94]. However, in another similar study, no significant difference was noticed between highly concentrated salt water and simple tap water balneotherapy [24]. Liman peloid application and bath therapy was also associated with benefits to severity score, time to recurrence, and a reduction in topical drug use than clay peloid and tap water [95].
This treatment form presented the most homogeneous treatment length, usually at around 3-4 weeks, although extremes of 6 days and 8 months were also noticed. Additionally, the average age of patients following these therapies was higher than for the other treatments, though this could be a simple incidental observation. The evidence on hand supports balneotherapy and climate therapy as complementary therapies for psoriasis, capable of even inducing remission. A special recommendation should be given to patients with early-onset psoriasis and those with a longer disease duration, while caution must be taken for immunocompromised individuals or those with a history of skin malignancies.

Limitations
The major limitation of this review is the exclusion of numerous articles written in Chinese or Korean that were unfortunately inaccessible and could have provided valuable insight into the effects of CAM methods in psoriasis. It is possible that the conclusions drawn would have differed considerably, had these studies also been incorporated. We are aware that the English literature is lacking in fields such as acupuncture and cupping therapy, and so practitioners are specialized in these interventions in Western countries, as opposed to those in Asia. Furthermore, several articles that we tried to verify through reference cross checking could not be found on any of the search engines we utilized. Another limitation is that some of the conclusions, especially concerning acupuncture and cupping, are drawn from single-patient case reports, which do not hold the same statistical significance as randomized controlled trials.

Conclusions
CAM, with reference to stress management interventions, balneo-, and climatotherapy, in conjunction with usual care, has the potential to help psoriasis patients reach remission faster and for longer periods of time compared to standard therapy alone. Concerning acupuncture, despite being popular in China even for the management of psoriasis, the English literature is as of yet inconclusive, whereas no evidence supports cupping therapy as being safe or effective, but potentially harmful due to the extremely high incidence of subsequent Koebner phenomenon. Therefore, these latter two options are not viable alternative treatment methods based on current available evidence. We emphasize that standard therapies, such as topical, systemic, and biologic agents, should always be considered before attempting CAM methods, since there is a larger body of evidence to support the effectiveness of these treatments. Furthermore, additional research in the form of prospective trials should be performed before establishing acupuncture and cupping as beneficial in psoriasis management.