Is alcoholism a form of depression, or are the two linked? While alcoholism is not a form of depression, both conditions have some common symptoms and possibly shared genetic links, The New York Times reports.

In fact, depression makes people more vulnerable to drinking problems and vice versa, said Shelly Greenfield, M.D. a professor of psychiatry at Harvard Medical School and director of McLean Hospital’s Alcohol and Drug Abuse Clinical and Health Services Research Program.

About a third of depressed people suffer from alcoholism, she said. Genetics makes some people more vulnerable to each — and perhaps the combination, Dr. Greenfield said, “but it’s not the whole story.”

Social factors, particularly in childhood, also play a key role. Victims of physical or sexual abuse, for example, are at higher risk for both alcoholism and depression later in life.

Depressed people who drink will most likely see their depression worsen, because alcohol is a depressant, tamping down the nervous system, said Kathleen Brady, M.D., a distinguished university professor at the Medical University of South Carolina.