Depression and NIH Women's Health Research

Signs, Symptoms, and Risk Factors

Depression is a mood disorder that is characterized by feelings of sadness, hopelessness, or worthlessness that last for at least 2 weeks. Although the severity and duration of symptoms can vary between individuals, people with depression often have difficulty concentrating, lose interest in hobbies or activities that they previously enjoyed, or have decreased energy levels. Their appetite and sleep cycle may also be affected. In some cases, they may have thoughts of harming themselves or committing suicide.¹

This condition is caused by a complex combination of biological, environmental, and psychological factors.² There are several types of depression, including major depressive disorder and seasonal affective disorder.³

Impact on Women’s Health

After puberty, women are approximately twice as likely as men to develop depression.^{4 - 7} The available evidence suggests that depression can present differently in women as well. Overall, the symptoms of depression tend to be more severe in women than men, and certain symptoms, such as weight gain, appetite disturbance, and impaired sleep, are more common in women.^{6 - 8} Comorbid anxiety also occurs more frequently in women than in men.^{4 , 6}

Women can also experience perinatal depression, which occurs during pregnancy or after childbirth and is marked by severe anxiety, sadness, and fatigue. Women with perinatal depression may have trouble taking care of themselves or others.⁹ Estrogen is known to have a neuroprotective effect on certain regions of the brain (e.g., hippocampus, amygdala); therefore, the fluctuations in estrogen levels that occur during a woman’s life (e.g., during perimenopause) can increase both sensitivity to stress and the risk of depression.^{10 , 11}

Diagnosis and Treatment

Generally, depression is diagnosed using a physical exam and a clinical history that includes a medical and family history and a discussion of substance use. There are no laboratory tests that can diagnose depression, but certain tests may be helpful in ruling out other medical conditions (e.g., thyroid disorders).¹²

Depression is often treated with pharmacotherapy, psychotherapy (e.g., cognitive behavior therapy), or a combination of the two.^{4 , 13} Research suggests that the efficacy of certain antidepressants varies between women and men. Specifically, several studies have reported that selective serotonin reuptake inhibitors may be more effective at managing depression in women.^{4 , 5} Some research has also suggested that women respond to lower doses of the fast-acting antidepressant ketamine than men and that they experience different adverse effects from ketamine (e.g., headaches, nausea, cognitive impairment disorders) and have more severe withdrawal symptoms.¹⁴

Ongoing Research

More research is needed to define the potential sex-specific differences in the long-term efficacy and safety of antidepressant therapies.¹⁴ In addition, researchers are investigating the role that genetic and epigenetic changes play in the sex differences seen in people with depression and how certain hormones, such as estrogen, can influence those markers for depression.^{7 , 15}

The National Institute of Mental Health (NIMH) invests in research that is investigating the causes of depression and methods to treat it effectively. One area of study involves developing methods to identify which treatments work best for specific individuals with depression. To do this, NIMH researchers are employing positron emission tomography scans and magnetic resonance imaging to learn more about the brains of people with major depressive disorder.¹⁶