Diabetic mothers at higher depression risk

Pregnant women and new mothers with diabetes had nearly double the risk of developing postpartum depression as women without diabetes, a new study reports, revealing a potential risk factor for a serious psychological disorder that affects more than 1 in 10 new mothers.

Researchers, led by Katy Backes Kozhimannil of Harvard Medical School and Harvard Pilgrim Health Care, analyzed health records of more than 11,000 low-income women enrolled in New Jersey's Medicaid program. They found that 15.2 percent of the women who had diabetes were depressed during pregnancy or in the first year after childbirth, compared with 8.5 percent of women who did not have diabetes. Those differences remained after adjusting the data for factors such as the age and race of the mothers.

"The good news from this study is that both diabetes and depression are treatable illnesses," Kozhimannil said in an interview. "Postpartum depression in particular is underdiagnosed and underdetected a lot of the time."

Diabetes and depression have been linked before, but this is the first study to examine diabetes and depression in new mothers. How one disorder might cause the other has not been untangled. Scientists have speculated on biological possibilities, such as how abnormal blood sugar and insulin levels might affect stress hormones. Psychosocial factors, such as the stress of managing a chronic illness like diabetes, also have been implicated in worsening depressive symptoms.

Women are routinely screened for diabetes between the 24th and 28th weeks of pregnancy, but screening for depression is not a standard part of care, Kozhimannil said.

Depression can be hard to identify because many of its symptoms are common experiences for new mothers, Kozhimannil said. Up to 80 percent of women go through the "baby blues," a milder mood disorder as they adjust to fluctuating hormones and life changes.

But postpartum depression is more severe and more persistent, marked by intense worry or panic about the baby's health.

The study was published in today's Journal of the American Medical Association.