Newswise — (New York – January 18, 2017) –– Researchers from the Icahn School of Medicine at Mount Sinai and the Karolinska Institutet have found that gestational diabetes raises the risk of postpartum depression (PPD) in first-time mothers. This is the largest study of its kind to date, including more than 700,000 women. The results were published online today in the journal Depression and Anxiety.

The researchers also established that women with a history of depression are more than 20 times more likely to experience PPD than mothers without a previous clinical diagnosis of depression. And while gestational diabetes alone increased risk for PPD, a history of maternal depression in conjunction with gestational diabetes further increased the likelihood of PPD.

“Most practitioners think of these as two isolated and very different conditions, but we now understand gestational diabetes and postpartum depression should be considered together,” says Michael E. Silverman, PhD, an Assistant Professor of Psychiatry at the Icahn School of Medicine at Mount Sinai, and lead author of the study. “While having diabetes increases PPD risk for all women, for those women who have had a past depressive episode, having diabetes during pregnancy makes it 70 percent more likely that they will develop PPD.”

In addition to gestational diabetes, the researchers studied more than a dozen other risk factors, including pre-gestational diabetes, for association with PPD in women with and without a history of depression. Among women with a history of depression, pre-gestational diabetes and mild preterm delivery increased risk. Young age, instrument-assisted or cesarean delivery, and moderate preterm delivery increased risk in women who had no history of depression.

Studying the modifying effect of maternal depression on pre- and perinatal PPD risk factors sheds new light on the relationship between diabetes and depression. Showing that a history of depression modifies some of the risks associated with obstetric and perinatal factors suggests that there may be different causal pathways of PPD in women with and without a history of depression.

PPD can result in negative personal and child developmental outcomes, and identifying previous depressive episodes as a risk factor for PPD allows doctors to pursue earlier interventions. “The reason a doctor asks if you smoke is because they know you are 20 times more likely to get cancer if you do. We believe OB/GYNs should now do the same for depression history,” Dr. Silverman said. “With this information, we can now intervene early, before the mother gives birth.”

This is the largest population-based study to date to characterize PPD in relation to depression history. Researchers used the nationwide Swedish Medical Birth Register, which includes information on all births in Sweden. Unlike in past studies, researchers relied on clinical diagnoses of PPD since symptom-based PPD inventories have a tendency to overestimate the prevalence of the condition.

The study was funded by the U.S. National Institute of Child Health and Development. The team included researchers from the Department of Psychiatry and The Seaver Autism Center for Research and Treatment at the Icahn School of Medicine at Mount Sinai; the Karolinska Institutet in Stockholm, Sweden; and Brown University.

About the Mount Sinai Health SystemThe Mount Sinai Health System is an integrated health system committed to providing distinguished care, conducting transformative research, and advancing biomedical education. Structured around seven hospital campuses and a single medical school, the Health System has an extensive ambulatory network and a range of inpatient and outpatient services—from community-based facilities to tertiary and quaternary care.

The System includes approximately 7,100 primary and specialty care physicians; 12 joint-venture ambulatory surgery centers; more than 140 ambulatory practices throughout the five boroughs of New York City, Westchester, Long Island, and Florida; and 31 affiliated community health centers. Physicians are affiliated with the renowned Icahn School of Medicine at Mount Sinai, which is ranked among the highest in the nation in National Institutes of Health funding per investigator. The Mount Sinai Hospital is in the “Honor Roll” of best hospitals in America, ranked No. 15 nationally in the 2016-2017 “Best Hospitals” issue of U.S. News & World Report. The Mount Sinai Hospital is also ranked as one of the nation’s top 20 hospitals in Geriatrics, Gastroenterology/GI Surgery, Cardiology/Heart Surgery, Diabetes/Endocrinology, Nephrology, Neurology/Neurosurgery, and Ear, Nose & Throat, and is in the top 50 in four other specialties. New York Eye and Ear Infirmary of Mount Sinai is ranked No. 10 nationally for Ophthalmology, while Mount Sinai Beth Israel, Mount Sinai St. Luke's, and Mount Sinai West are ranked regionally. Mount Sinai’s Kravis Children’s Hospital is ranked in seven out of ten pediatric specialties by U.S. News & World Report in "Best Children's Hospitals."

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About the Seaver Autism Center for Research and Treatment at Mount SinaiThe Seaver Autism Center for Research and Treatment at Mount Sinai conducts progressive research studies aimed at understanding the multiple causes of autism spectrum disorder (ASD). The multidisciplinary team is comprised of experts in the fields of genetics, molecular biology, model systems, neuroimaging, biomarkers, diagnosis, and experimental therapeutics who are dedicated to discovering the biological causes of ASD. The Center strives to develop innovative diagnostics and treatments for integration into the provision of personalized, comprehensive assessment and care for people with ASD. The Seaver Autism Center was founded through the generous support of the Beatrice and Samuel A. Seaver Foundation. For more information, visit www.seaverautismcenter.org.

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