title: Factors related to age at natural menopause: longitudinal analyses from SWAN.
abstract: Early age at the natural final menstrual period (FMP) or menopause has been associated with numerous health outcomes and might be a marker of future ill health. However, potentially modifiable factors affecting age at menopause have not been examined longitudinally in large, diverse populations. The Study of Women's Health Across the Nation (SWAN) followed 3,302 initially premenopausal and early perimenopausal women from 7 US sites and 5 racial/ethnic groups, using annual data (1996-2007) and Cox proportional hazards models to assess the relation of time-invariant and time-varying sociodemographic, lifestyle, and health factors to age at natural FMP. Median age at the FMP was 52.54 years (n = 1,483 observed natural FMPs). Controlling for sociodemographic, lifestyle, and health factors, we found that racial/ethnic groups did not differ in age at the FMP. Higher educational level, prior oral contraceptive use, and higher weight at baseline, as well as being employed, not smoking, consuming alcohol, having less physical activity, and having better self-rated health over follow-up, were significantly associated with later age at the FMP. These results suggest that age at the natural FMP reflects a complex interrelation of health and socioeconomic factors, which could partially explain the relation of late age at FMP to reduced morbidity and mortality.
authors.affiliation: University of California Davis School of Medicine, One Shields Avenue, Davis, CA 95616, USA. ebgold@ucdavis.edu
authors.forename: Ellen B
authors.initials: EB
authors.lastname: Gold
authors.forename: Sybil L
authors.initials: SL
authors.lastname: Crawford
authors.forename: Nancy E
authors.initials: NE
authors.lastname: Avis
authors.forename: Carolyn J
authors.initials: CJ
authors.lastname: Crandall
authors.forename: Karen A
authors.initials: KA
authors.lastname: Matthews
authors.forename: L Elaine
authors.initials: LE
authors.lastname: Waetjen
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Lee
authors.forename: Rebecca
authors.initials: R
authors.lastname: Thurston
authors.forename: Marike
authors.initials: M
authors.lastname: Vuga
authors.forename: Siobán D
authors.initials: SD
authors.lastname: Harlow
mesh_terms: D000328:Adult; D000367:Age Factors; D003276:Contraceptives, Oral / Q000009:adverse effects; D005260:Female; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008593:Menopause / Q000502:physiology*; D008594:Menopause, Premature / Q000502:physiology; D008875:Middle Aged; D016016:Proportional Hazards Models; D044469:Racial Groups / Q000706:statistics & numerical data; D012907:Smoking / Q000009:adverse effects; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology
chemical_list: D003276:Contraceptives, Oral
keywords: age; education; ethnicity; menopause; oral contraceptives; race; smoking; weight