title: Relation between premenstrual syndrome and equol-production status.
abstract: OBJECTIVE
  Consumption of isoflavones, which are predominantly derived from soybeans, reduces the risk of estrogen-related diseases, such as menopausal symptoms, breast cancer, osteoporosis, and cardiovascular disease. Equol is more bioavailable than other soy isoflavones, and equol producers are believed to benefit to a greater extent. This study was conducted to evaluate the relation between premenstrual syndrome (PMS) and equol-production status in Japanese reproductive-age women.
  
  
  METHODS
  This was a cross-sectional, observational study. The study included 144 Japanese women aged 20-45 years. PMS patients (n = 46) were recruited at three obstetrics and gynecology clinics. Control group women (n = 98) who were not receiving therapy for PMS were recruited from the local area by advertisement. The participants' equol-production status was determined using urine samples collected after a soy challenge test.
  
  
  RESULTS
  The prevalence of equol producers was 41.8% in the control group and 23.9% in the patient group (P = 0.042). Using univariate analysis, significant risk factors for equol non-producers were being a PMS patient and being younger. In multivariate analysis with a step-wise model, being a PMS patient (odds ratio, 2.342; 95% confidence interval, 1.021-5.698) was shown to be a significant risk factor for being an equol non-producer.
  
  
  CONCLUSIONS
  This study showed a relation between PMS and equol-production status in Japanese women.
authors.affiliation: Division of Women's Health, Research Institute of Traditional Asian Medicine, Kindai University School of Medicine, Osaka, Japan. take@med.kindai.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Takeda
authors.affiliation: Saga Nutraceuticals Research Institute of Otsuka Pharmaceutical Co., Ltd, Saga, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Ueno
authors.affiliation: Saga Nutraceuticals Research Institute of Otsuka Pharmaceutical Co., Ltd, Saga, Japan.
authors.forename: Shigeto
authors.initials: S
authors.lastname: Uchiyama
authors.affiliation: Hiramatsu Women's Clinic, Osaka, Japan.
authors.forename: Keizo
authors.initials: K
authors.lastname: Hiramatsu
authors.affiliation: Division of Women's Health, Research Institute of Traditional Asian Medicine, Kindai University School of Medicine, Osaka, Japan.
authors.forename: Masami
authors.initials: M
authors.lastname: Shiina
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D060754:Equol / Q000652:urine*; D005260:Female; D006801:Humans; D008875:Middle Aged; D011293:Premenstrual Syndrome / Q000652:urine*; D012307:Risk Factors; D045730:Soy Foods; D055815:Young Adult
chemical_list: D060754:Equol
keywords: equol; isoflavone; premenstrual dysphoric disorder; premenstrual syndrome; soy