Effect of S-equol supplementation on menopausal symptoms, sleep complaints, pain, and work engagement: an exploratory, multicentre open-label study in Spanish women

Although S- equol has demonstrated efficacy in randomized trials conducted mainly in Japanese and American populations, evidence in European populations remains limited. Menopausal symptoms have been shown to negatively affect work productivity and engagement, yet interventions targeting both symptom relief and work-related outcomes remain poorly studied. This exploratory, multicentre, open-label, single-arm study aimed to confirm previous observations also in European women and further explore the impact of S- equol on quality of life and work engagement. Subjects received daily SE5-OH tablets providing 10 mg S -equol for 12 weeks, followed by 4 weeks without supplementation. A total of 159 women received at least one dose (included in the Intention to treat population) and 124 followed the treatment and visit schedule described in the study protocol (included in the Per Protocol analysis). Study participants had a mean (SD) age of 52.5 (4.1) years and included pre- (1.6%), peri- (26.6%) and post-menopausal (60.5%) women. The primary endpoint was Menopause Rating Scale (MRS) and secondary endpoints included Vasomotor Symptoms (VMS), Utrecht Work Engagement Scale (UWES) and Visual Analogue Scale (VAS) for pain and sleep complaints. Participants recorded their hot flashes/night sweats’ frequency daily and menopausal symptoms’ severity, pain, sleep complaints and work engagement were assessed at follow-up visits (at week 4, 12 and 16). Changes from baseline were analysed using paired parametric or non-parametric tests, as appropriate. After 12 weeks, the MRS was significantly improved (-11.6 points; p < 0.0001) and a significant improvement was also observed on VMS frequency (20% to 70%; p < 0.0001), pain (-1.1 points for shoulder pain and -1.9 points for low back pain; p < 0.0001), sleep complaints (-2.1 points; p < 0.0001) and work engagement (0.2 points; p = 0.0097). The results of the study are in line with previous findings, showing an improvement in menopausal symptoms and quality of life for women experiencing moderate to severe menopausal symptoms. S -equol may be considered as a potential complementary, non-hormonal option to relieve menopausal symptoms across different menopausal stages. clinicaltrials.gov ID: NCT06398236 – retrospectively registered on 9 April 2024.