Depression: Examining the Sex/Gender Differences and Links to Other Diseases
Depression is not only a significant public health concern; it is also linked to many other prevalent diseases. The interaction of depression with other diseases was recently discussed at the Office of Research on Women's Health (ORWH) Women's Health Seminar Series: Sex and Gender Research: the Interaction of Depression with Other Diseases. Several current and former NIMH grantees participated in the discussions.
Depression and Women: Developmental Risks
NIMH grantee Jill Goldstein, Ph.D., Professor of Psychiatry and Medicine, Harvard Medical School and Director of Research with Connors Center for Women's Health and Gender Biology, Brigham and Women's Hospital, discussed sex differences that are pervasive in depression. Dr. Goldstein stated that because depression is seen more frequently in females, trying to understand these differences will help clinicians tailor sex specific treatments.
"The higher incidence of major depressive disorder in women is initiated during sexual differentiation in the brain. Fetal development, puberty, pregnancy, and menopause are all windows of opportunity in which to study the differences seen clinically in rates of major depression and mood disorder," explained Dr. Goldstein.
Additionally, she stated that there is a similarity of developmental risk factors during the second and third trimesters of pregnancy for depression and cardiovascular disease. These factors include: small gestational age, low birth weight, pre-eclampsia, and prenatal exposure of the mother to famine.
"Sex differences exist in every tissue of the body; disruption in the amygdala, hippocampus, hypothalamus, and white matter lead to the sex differences seen in depression, mood disorders, endocrine dysfunction, and heart rate, " said Dr. Goldstein.
Bone Health and Depression
Osteoporosis is also a major public health problem costing billions of health care dollars and affecting millions of individuals each year. However, its relationship to depression is still largely unrecognized. NIDDK investigator and former NIMH collaborator Giovanni Cizza, M.D., Ph.D., M.H.Sc. presented data showing that chronic stress and depression result in significant bone loss, particularly in the hip.
"We found that one in five premenopausal women with major depressive disorder exhibited low bone mineral density in the hip area. Depressed premenopausal patients exhibited the equivalent of one year of bone loss seen in post-menopausal patients," said Dr. Cizza.
Cancer and Depression
Cancer is another health concern in which depression can play a role in the course of treatment. While ten to thirty percent of people with cancer are found to be depressed, the rates of depression vary with age of onset of cancer, type of cancer, and stage of treatment. Mary Jane Massie, M.D., attending psychiatrist at Memorial Sloan-Kettering Cancer Center and Professor of Clinical Psychiatry at the Weill Medical college of Cornell University presented data showing that at diagnosis a third of patients said they were depressed, fifteen percent said they were at one year after diagnosis and forty-five percent after recurrence.
"In my practice, very young cancer patients suffer from major depression as do those with more pain, specific types of chemotherapy, poor support systems, less optimism, low self esteem, stressful life events, and a history of trauma or substance abuse. However, in a cancer setting, many patients do not tell their oncologists that they are depressed. They do not want to distract the doctor, they do not want anymore medication, or they feel an additional sense of stigma related to depression, "stated Dr. Massie.
"While symptoms of depression may overlap with symptoms of the cancer, it is very important for oncologists to use screening tools for depression and to tell their patients that there is help," emphasized Massie.
Cardio Health and Depression
Viola Vaccarino, M.D., Ph.D., Professor of Medicine, Emory School of Medicine, Division of Cardiology, focused on the social and behavioral determinates of cardiovascular disease in women. Depression is more prevalent in heart patients that in the general population, especially in young women with acute heart disease. While many studies have been done showing that depression is significantly related to cardiovascular disease, the multiple pathways of disease affected by depression, such as inflammation, are still being studied. Importantly, genetic medicine is playing a significant role in determining the genetic risk factors that are sex specific in heart disease.
"The links between depression and cardiovascular disease may be more important for women. Obviously, interventions must be tailored to women's stressors." said Vaccarino. "However, treating both depression and CVD is controversial. No study has shown that treating both conditions results in improved CVD and this is disappointing," cautioned Dr. Vaccarino.
Sex Differences in Disease: More Exploration Essential
Sex differences in disease patterns are pervasive in clinical medicine. In trying to understand these sex/gender characteristics, treatments tailored to individuals will be more effective in lessening the disease burden of depression and its many other co-occurring diseases.