Duration of Lactation and Incidence of the Metabolic Syndrome in Women of Reproductive Age According to Gestational Diabetes Mellitus Status: A 20-Year Prospective Study in CARDIA (Coronary Artery Risk Development in Young Adults)

Abstract

OBJECTIVEThe objective of the study was to prospectively assess the association between lactation duration and incidence of the metabolic syndrome among women of reproductive age.RESEARCH DESIGN AND METHODSParticipants were 1,399 women (39% black, aged 18–30 years) in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, an ongoing multicenter, population-based, prospective observational cohort study conducted in the U.S. Women were nulliparous and free of the metabolic syndrome at baseline (1985–1986) and before subsequent pregnancies, and reexamined 7, 10, 15, and/or 20 years after baseline. Incident metabolic syndrome case participants were identified according to National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Complementary log-log models estimated relative hazards of incident metabolic syndrome among time-dependent lactation duration categories by gestational diabetes mellitus (GDM) adjusted for age, race, study center, baseline covariates (BMI, metabolic syndrome components, education, smoking, physical activity), and time-dependent parity.RESULTSAmong 704 parous women (620 non-GDM, 84 GDM), there were 120 incident metabolic syndrome case participants in 9,993 person-years (overall incidence rate 12.0 per 1,000 person-years; 10.8 for non-GDM, 22.1 for GDM). Increased lactation duration was associated with lower crude metabolic syndrome incidence rates from 0–1 month through >9 months (P < 0.001). Fully adjusted relative hazards showed that risk reductions associated with longer lactation were stronger among GDM (relative hazard range 0.14–0.56; P = 0.03) than non-GDM groups (relative hazard range 0.44–0.61; P = 0.03).CONCLUSIONSLonger duration of lactation was associated with lower incidence of the metabolic syndrome years after weaning among women with a history of GDM and without GDM, controlling for preconception measurements, BMI, and sociodemographic and lifestyle traits. Lactation may have persistent favorable effects on women's cardiometabolic health.

Breastfeeding History and Risk of Stroke Among Parous Postmenopausal Women in the Women's Health Initiative

“…Many studies have reported that longer duration of breastfeeding may reduce long‐term risk of cardiovascular markers including hypertension, hyperlipidemia, and metabolic syndrome 32, 33, 34, 35, 36, 37, 47. Few studies have measured cardiovascular markers longitudinally from time of breastfeeding to menopause, and those that have are observational studies that are limited to self‐reported disease outcomes.…”

“…Research findings point to the protective effect of breastfeeding on maternal health including a reduced risk of breast cancer and ovarian cancer and improved cardiovascular health 29, 30, 31. Women who report more than 9 cumulative months of breastfeeding over their reproductive lifetime are less likely to develop hypertension, hyperlipidemia, and metabolic syndrome 32, 33, 34, 35, 36, 37. Further, evidence suggests that a longer duration of breastfeeding is associated with a lower risk of developing type 2 diabetes mellitus,38, 39, 40, 41, 42, 43 and reduced maternal postpartum weight 44, 45, 46, 47…”

“…Whereas studies to date have largely focused on the protective effect of breastfeeding on cardiovascular risk factors,32, 33, 34, 35, 36, 37, 55, 56 few studies have assessed whether breastfeeding protects against risk of stroke and whether this association differs by race/ethnicity. Because Hispanic and non‐Hispanic black women experience low breastfeeding rates and are at higher risk for stroke compared with non‐Hispanic white women, there is a need to examine this relationship so that future intervention programming may focus on specific populations that carry the largest health burden of stroke.…”

Breastfeeding and the Risk of Maternal Cardiovascular Disease: A Prospective Study of 300 000 Chinese Women

“…Such pregnancy‐related cardiometabolic changes may reverse more quickly and more completely with breastfeeding, with several studies reporting that women who breastfeed have more favorable cardiometabolic profiles compared with women who do not breastfeed 3, 4, 5. Longer breastfeeding duration has also been associated with a lower risk of metabolic syndrome,6 hypertension,7, 8 and diabetes mellitus in later life,9 which may lead to long‐term protective benefits for cardiometabolic diseases.…”

Characteristics of metabolic syndrome in women

“…По-казано, что большое количество беременностей и родов повышает риск развития МС [6,7] независимо от нали-чия ожирения до беременности и увеличения массы тела во время беременности. Наоборот, более длительное грудное вскармливание ассоциировано с низким рис-ком МС [6,8]. Наличие гестационного диабета или НТГ при беременности являются факторами риска разви-тия МС в течение трех месяцев после родов [9].…”