TY - JOUR

T1 - Lactation Duration and Long-term Risk for Incident Type 2 Diabetes in Women With a History of Gestational Diabetes Mellitus

AU - Ley, Sylvia H.

AU - Chavarro, Jorge E.

AU - Li, Mengying

AU - Bao, Wei

AU - Hinkle, Stefanie N.

AU - Wander, Pandora L.

AU - Rich-Edwards, Janet

AU - Olsen, Sjurdur

AU - Vaag, Allan

AU - Damm, Peter

AU - Grunnet, Louise G.

AU - Mills, James L.

AU - Hu, Frank B.

AU - Zhang, Cuilin

PY - 2020/4

Y1 - 2020/4

N2 - OBJECTIVE We examined the association of lactation duration with incident type 2 diabetes among women with a history of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS We monitored 4,372 women with a history of GDM participating in the Nurses’ Health Study II for incident type 2 diabetes over 25 years up to 2017. Lactation history was obtained through follow-up questionnaires to calculate lactation duration. Follow-up blood samples were collected from a subset of these women at median age of 58 years through the Diabetes & Women’s Health Study. RESULTS We documented 873 incident cases of type 2 diabetes during 87,411 person-years of follow-up. Longer duration of lactation was associated with lower risk of type 2 diabetes for both total lactation (hazard ratio 1.05 [95% CI 0.83–1.34] for up to 6 months, 0.91 [0.72–1.16] for 6–12 months, 0.85 [0.67–1.06] for 12–24 months, and 0.73 [0.57–0.93] for >24 months, compared with 0 months; P-trend 5 0.003) and exclusive breastfeeding (P-trend 5 0.002) after adjustment for age, ethnicity, family history of diabetes, parity, age at first birth, smoking, diet quality, physical activity, and prepregnancy BMI. Longer duration of lactation was also associated with lower HbA1c, fasting plasma insulin, and C-peptide concentrations among women without type 2 diabetes at follow-up (all adjusted P-trend £0.04). CONCLUSIONS Longer duration of lactation is associated with a lower risk of type 2 diabetes and a favorable glucose metabolic biomarker profile among women with a history of GDM. The underlying mechanisms and impact on diabetes complications, morbidity, and mortality remain to be determined.

AB - OBJECTIVE We examined the association of lactation duration with incident type 2 diabetes among women with a history of gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS We monitored 4,372 women with a history of GDM participating in the Nurses’ Health Study II for incident type 2 diabetes over 25 years up to 2017. Lactation history was obtained through follow-up questionnaires to calculate lactation duration. Follow-up blood samples were collected from a subset of these women at median age of 58 years through the Diabetes & Women’s Health Study. RESULTS We documented 873 incident cases of type 2 diabetes during 87,411 person-years of follow-up. Longer duration of lactation was associated with lower risk of type 2 diabetes for both total lactation (hazard ratio 1.05 [95% CI 0.83–1.34] for up to 6 months, 0.91 [0.72–1.16] for 6–12 months, 0.85 [0.67–1.06] for 12–24 months, and 0.73 [0.57–0.93] for >24 months, compared with 0 months; P-trend 5 0.003) and exclusive breastfeeding (P-trend 5 0.002) after adjustment for age, ethnicity, family history of diabetes, parity, age at first birth, smoking, diet quality, physical activity, and prepregnancy BMI. Longer duration of lactation was also associated with lower HbA1c, fasting plasma insulin, and C-peptide concentrations among women without type 2 diabetes at follow-up (all adjusted P-trend £0.04). CONCLUSIONS Longer duration of lactation is associated with a lower risk of type 2 diabetes and a favorable glucose metabolic biomarker profile among women with a history of GDM. The underlying mechanisms and impact on diabetes complications, morbidity, and mortality remain to be determined.

U2 - 10.2337/dc19-2237

DO - 10.2337/dc19-2237

M3 - Journal article

C2 - 32041900

AN - SCOPUS:85082146828

VL - 43

SP - 793

EP - 798

JO - Diabetes Care

JF - Diabetes Care

SN - 0149-5992

IS - 4

ER -