Associations of breastfeeding history with metabolic syndrome and cardiovascular risk factors in community-dwelling parous women: The Japan Multi-Institutional Collaborative Cohort Study

PLoS One. 2022 Jan 19;17(1):e0262252. doi: 10.1371/journal.pone.0262252. eCollection 2022.

Abstract

Objective: The aim of the present study was to investigate the associations between breastfeeding and the prevalence of metabolic syndrome in community-dwelling parous women and to clarify whether the associations depend on age.

Methods: The present cross-sectional study included 11,118 women, aged 35-69 years. Participants' longest breastfeeding duration for one child and their number of breastfed children were assessed using a self-administered questionnaire, and their total breastfeeding duration was approximated as a product of the number of breastfed children and the longest breastfeeding duration. The longest and the total breastfeeding durations were categorized into none and tertiles above 0 months. Metabolic syndrome and cardiovascular risk factors (obesity, hypertension, dyslipidemia, and hyperglycemia) were defined as primary and secondary outcomes, respectively. Associations between breastfeeding history and metabolic syndrome or each cardiovascular risk factor were assessed using multivariable unconditional logistic regression analysis.

Results: Among a total of 11,118 women, 10,432 (93.8%) had ever breastfed, and 1,236 (11.1%) had metabolic syndrome. In participants aged <55 years, an inverse dose-response relationship was found between the number of breastfed children and the prevalence of metabolic syndrome; multivariable-adjusted odds ratios for 1, 2, 3, and ≥4 breastfed children were 0.60 (95% confidence interval [CI]: 0.31 to 1.17), 0.50 (95% CI: 0.29 to 0.87), 0.44 (95% CI: 0.24 to 0.84), and 0.35 (95% CI: 0.14 to 0.89), respectively. The longest and total breastfeeding durations of longer than 0 months were also associated with lower odds of metabolic syndrome relative to no breastfeeding history in participants aged <55 years. In contrast, all measures of breastfeeding history were not significantly associated with metabolic syndrome and cardiovascular risk factors in participants aged ≥55 years old.

Conclusions: Breastfeeding history may be related to lower prevalence of metabolic syndrome in middle-aged parous women.

MeSH terms

  • Adult
  • Aged
  • Breast Feeding / statistics & numerical data*
  • Cardiovascular Diseases / epidemiology*
  • Cardiovascular Diseases / prevention & control
  • Cross-Sectional Studies
  • Female
  • Humans
  • Independent Living / statistics & numerical data*
  • Japan / epidemiology
  • Metabolic Syndrome / epidemiology*
  • Metabolic Syndrome / prevention & control
  • Middle Aged
  • Prevalence
  • Surveys and Questionnaires

Grants and funding

This study was supported by Grants-in-Aid for Scientific Research for Priority Areas of Cancer (No. 17015018) and Innovative Areas (No. 221S0001) from the Japan Society for the Promotion of Science, and by the Platform of Supporting Cohort Study and Biospecimen Analysis (CoBiA, JSPS KAKENHI Grant Number 16H06277) from the Japanese Ministry of Education, Culture, Sports, Science and Technology. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.