The effects of psychological interventions on menopausal hot flashes: A systematic review

Abstract Background Menopause is a normal physiological phenomenon, closely identified with a great deal of physical-psychological symptoms, including hot flashes (HFs) with a prevalence rate of 20-80%. Various pharmacological and non-pharmacological interventions have been thus far practiced to reduce this common symptom of the menopausal transition. Objective This systematic review was conducted to evaluate the effects of psychological interventions on menopausal HFs. Materials and Methods In this review, the databases of Google Scholar, Scopus, PubMed, Web of Science, Science Direct, the Cochrane Library, and Scientific Information Database were searched applying the Boolean searching operators as well as the keywords of `hot flashes', `menopause', `psychological intervention', and `vasomotor symptoms'. Accordingly, a total number of 20,847 articles published from January 2000 to June 2019 were retrieved. After excluding the duplicate and irrelevant ones, the risk of bias of 19 clinical or quasi-experimental clinical trials was assessed using the Cochrane collaboration tool. Results The interventions implemented in the studies on menopausal HFs included cognitive behavioral therapy, mindfulness-based stress reduction, hypnotherapy, and relaxation techniques. All of the articles reported improvements in HFs in postmenopausal women, except for 4 studies. Conclusion Based on the findings of this systematic review, psychological interventions, especially cognitive behavioral therapy and relaxation techniques, are potentially effective for vasomotor symptoms and HFs in healthy postmenopausal women, although the quality of published research on this topic is sometimes questionable.


Introduction
Menopause is a normal physiological phenomenon in women aged 47-55 yr (1,2). It is often closely identified with common symptoms such as anxiety, depression, stress, mood disorders, sexual concerns, night sweats, and in particular hot flashes (HFs) (1,(3)(4)(5)(6). HFs represents the most common complication of menopause, with a prevalence rate of 20-80% (7)(8)(9). HFs are a sudden feeling of warmth in the upper body, including the face, neck, and chest, which may spread to the legs (5). This symptom of menopausal transition often results in a high resting heart rate, fatigue, nausea, increased metabolism, and anxiety (8). Studies show that some women might experience HFs for more than 20 yr. Therefore, it is of paramount importance to focus attention on this issue in women's health (8,10).
Studies in this line have demonstrated that hormone therapy is the principal treatment for HFs in postmenopausal women. However, its continuous use might increase the risk of breast cancer, cardiovascular diseases, stroke, venous complications, and thromboembolism (4,5). Non-hormonal treatments might lead to potential side effects and incur considerable costs in the long term (8). Concerning these complications and risks, women tend to benefit from non-pharmacological treatments such as complementary medicine and psychological interventions (7,26).
Studies have shown that the use of psychological interventions such as CBT, MBSR, and hypnotherapies lessen the frequency and severity of HFs, enhance sleep quality, and reduce night sweats, depression, and anxiety in postmenopausal women (4,8,24,27). However, some surveys have suggested that psychological interventions might fail to lessen HFs or improve menopause symptoms even though their results have been non-significant (20,22,28). The lack of significant findings can be attributed to different measurement tools and small sample sizes.
As the results of these studies regarding the effects of psychological interventions on menopausal HFs are contradictory, a structured, systematic review was conceived as one way to overcome these inconsistencies since it brings together a series of related investigations and allows readers to consider the results of multiple studies on the same topic simultaneously (29,30). A comprehensive overview of the available literature in this field indicated that previous systematic reviews had solely evaluated the effects of non-pharmacological treatments (31), medicinal plants (14), and relaxation techniques (32)

Research question
This study was a systematic review carried out based on the performed reporting items for systematic reviews and meta-analyses (PRISMA) guidelines (33,34

Data extraction and quality assessment
The data including authors' names, year, study design, location, goals, age, sample size, tools, type of interventions, duration of intervention, follow-up, outcomes, and results were extracted following the abstracts' assessment and review, and full texts of the eligible articles. Finally, the extracted data were classified and reported as a systematic review and illustrated in tables I and II.
The risk of bias of the included articles was assessed with the Cochrane collaboration tool (35,36). The risk of bias was assessed for each study using the following 7 items: random sequence generation and allocation concealment

Search results and descriptions of articles
At the first stage, 20,843 articles were obtained by searching the databases, and 4 articles were found manually. However, 197 articles remained once the duplicate and unrelated studies were eliminated. In the end, 134 and 44 articles were respectively excluded after reviewing their abstracts and reading their full texts, which led to the remaining 19 articles (Figure 1).

Article review and study participants
The subjects recruited in the selected articles were women who presented with the symptoms of HFs, at premenopausal, menopausal, and postmenopausal stages. Moreover, the participants' age range was 18-77 yr. (age was not been mentioned in 2 studies (10, 27)).

CBT
CBT is a structured, short-term, and skillsfocused psychotherapy and it is a combination of cognitive and behavioral therapies. The main approach in this treatment gives priority to the role of thoughts, beliefs, maladaptive perceptions, and cognitions to attain compatible thoughts and behaviors (4,39). 4 studies with high quality (low risk) in this systematic review evaluated the effects of CBT on menopausal HFs (4,7,(16)(17)(18)(19)(20)(21)(22), which involved 4-10 intervention sessions held for 1.5-2 hr. The intervention sessions also provided psychoeducation about menopause and HFs, stress management, problem-solving, cognitive and behavioral strategies to help manage HFs, relaxation techniques, breathing techniques, Kegel exercises, as well as identification and control of excessive worries and irrational beliefs.

MBSR
Mindfulness represents a meditation style that underlines the importance of awareness at the present moment (40). MBSR is a structured group program that uses mindfulness meditation to understand, evaluate, and deal with chronic diseases and their symptoms (24). In this review, one study with high quality (low risk) reflected on the effects of MBSR on HFs in postmenopausal women. 7 weekly sessions (one session per wk) were held for 2.5 hr, and one session (morning and evening) was organized at the end of the 6 th wk (24). During the intervention sessions, the actions included body scan meditation, intentionsetting meditation, and mindfulness-stretching exercises to develop awareness (mindfulness) during movements. Besides, all of participants in the study received CDs as guided instructions for practiced mindfulness at home for 45 min, 6 days a wk.

Hypnotherapy
Hypnotherapy refers to one of the psychological interventions and transient states caused by changes in accuracy and focus. This notion includes changes in consciousness and memory, increased sensitivity, inclusiveness, and imaginations that would not normally be possible (8,40). One study with high quality (low risk) in this systematic review assessed the impacts of hypnotherapy on HFs in postmenopausal women (5,8,25). In this study, 5 weekly intervention sessions (one session per wk) were held for 45 min. Hypnotic interventions also included induction and instruction in self-hypnosis practices towards the therapeutic goals of reduction of HFs. The participants were provided with a hypnotic suggestion for mental imagery involving coolness, safe-place imagery, hypnotic relaxation, and symptom reduction. Moreover, they were given a CD containing information about HFs for use as a home guide.

Relaxation techniques
Relaxation is a simple, beneficial, and executable technique in behavior therapy that can be easily performed with simple training (40). Accordingly, applied relaxation (AR) is one type of relaxation practiced in different uncomfortable situations with quick relaxation and proper breathing (28). In this review, 3 studies with high quality (low risk) evaluated the effects of relaxation techniques on menopause-induced HFs (10,(26)(27)(28)41). In 3 articles, 12 weekly intervention sessions (one session per wk) were held for 60 min (26,27,41). Another study included 5 group sessions (every other day) and one month of daily relaxation practices at home (10). The intervention sessions further provided information about menopause, theories about HFs, progressive relaxation, differential relaxation, fast relaxation, release-only relaxation, application development training, and conservation programs aimed at coping with vasomotor symptoms such as HFs.

Tools
The outcome of HFs in postmenopausal women was measured in all of the studies. Only one study implemented a researcher-made questionnaire to assess this condition (10), and the rest utilized various standard tools. In this context, 6 studies used the Hot Flash Related Daily Interference Scale (4,5,8,24,25,28), and 5 studies applied the Hot Flash Rating Scale (7,(17)(18)(19)22). On the other hand, 4 studies implemented the Blatt and Kupperman Menopausal Index (16,20,27,41), whereas 2 articles administered the Menopause Rating Scale (21,26). Furthermore, 2 studies employed the Hot Flash Symptom Diary (8,25) while one study applied the Hot Flash-Intensity scores (23).

Discussion
This systematic review was performed on 19 studies to evaluate the effects of psychological interventions on menopausal HFs. This was a review of studies related to various psychological interventions conducted with menopausal women.
From the 19 studies, 9 studies were of a high quality and low risk of bias.
In this review and according to previous studies (7,18,19), CBT improved and decreased the frequency of HFs in postmenopausal women by altering thoughts and behaviors, and through a particular focus on vasomotor symptoms and HFs (4,17).
In the present review, MBSR was also recognized as an efficient intervention targeting The answer to this question is unclear. Another potential confounding factor in this review was the time effect, because HFs decrease in frequency and intensity over time (43). To reduce the effect of this potential confounding factor, instead of using a control group, the researcher could measure the outcome at 2 different pre-intervention time points to obtain 2 baseline assessments (44).

Suggestions
There is limited evidence for the impact of effective psychological therapies on symptoms of post-menopausal women. Previous studies have however shown that HF symptoms in breast cancer survivors are more common, severe and distressing than in women who have not had cancer (48,49). Therefore, one of our suggestions is to compile a review article evaluating the effects of psychological interventions on HFs in breast cancer survivors. Further assessment on the effects of these interventions on HFs and other symptoms of menopause with high quality studies, such as randomized controlled trials, is another suggestion of this study. In addition, there is insufficient evidence to guide clinical practice for physicians, and conducting high-quality studies can be a step towards developing these guidelines.

Strengths and limitations
The major strength of this study was that it was a systematic review performed based on the reporting items for systematic reviews and metaanalyses (PRISMA) guidelines. Another strength was the use of a comprehensive search strategy in electronic databases. One of the main limitations of this study was the low number of high-quality studies available for this review. In addition, many of these studies had a high risk of bias due to the absence of adequate blinding. This bias is often an integral part of psychological studies, although evaluators may be blinded for treatment. Also, conducting a meta-analysis was impossible due to differences in and heterogeneity of the studies.

Conclusion
Based on the findings of this systematic review, psychological interventions, especially CBT and relaxation techniques are potentially effective for reducing vasomotor symptoms and HFs in healthy postmenopausal women, although the quality of