title: Risk of Sjögren's syndrome in Taiwanese female adults with irregular menstrual cycles: a population-based case-control study.
abstract: Primary Sjögren's syndrome (pSS) is a progressive systemic autoimmune disorder with a strong female predominance. Hormonal influences are thought to play a role in the development of pSS. However, no studies have specifically evaluated the association between irregular menstrual cycles and pSS. Therefore, using a health claims database, this study investigated the risk of pSS in women with irregular menstrual cycles. We conducted a case-control study using the Taiwan's National Health Insurance Research Database. A total of 360 patients diagnosed with pSS (International Classification of Diseases, ninth revision, clinical modification, ICD-9-CM code 710.2) between 2001 and 2012 were identified. Controls were frequency-matched at a rate of 5:1 to the cases by five-year age interval and index year. Both cases and controls were retrospectively traced back until 2001 for the diagnosis of irregular menstrual cycles (ICD-9-CM code 626.4). The risk of pSS was assessed using multivariate logistic regression analyses. Irregular menstrual cycles were significantly associated with pSS [adjusted odds ratio, (AOR) = 1.38, p = 0.027], after adjusted for insured amount, urbanization level, and thyroid disorder. In addition, when the data were stratified by three age categories, only the patients in the age category of 45-55 years showed significant association between irregular menstrual cycles and pSS (AOR = 1.74, p = 0.005). In this nationwide, population-based case-control study, we found a significant increased risk of pSS in female patients with irregular menstrual cycles, particularly those in their mid-forties to mid-fifties.
authors.affiliation: Division of Allergy, Immunology and Rheumatology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi County, Taiwan.|School of Medicine, Tzu Chi University, Hualien City, Taiwan.
authors.forename: Ming-Chi
authors.initials: MC
authors.lastname: Lu
authors.affiliation: School of Medicine, Tzu Chi University, Hualien City, Taiwan.|Division of Obstetrics and Gynecology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi County, Taiwan.
authors.forename: Min-Chih
authors.initials: MC
authors.lastname: Hsieh
authors.affiliation: Department of Medical Research, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi County, Taiwan. m.koo@utoronto.ca.|Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada. m.koo@utoronto.ca.
authors.forename: Malcolm
authors.initials: M
authors.lastname: Koo
authors.affiliation: Division of Allergy, Immunology and Rheumatology, Dalin Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Chiayi County, Taiwan. tzuchilai@gmail.com.|School of Medicine, Tzu Chi University, Hualien City, Taiwan. tzuchilai@gmail.com.
authors.forename: Ning-Sheng
authors.initials: NS
authors.lastname: Lai
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D016208:Databases, Factual; D005260:Female; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology*; D008599:Menstruation Disturbances / Q000150:complications*; D008875:Middle Aged; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D012859:Sjogren's Syndrome / Q000175:diagnosis* / Q000209:etiology; D013624:Taiwan; D055815:Young Adult
keywords: Autoimmune diseases; Menstruation disturbances; Sicca syndrome; Sjögren’s syndrome