Analysis of four genome-wide association studies indicated shared genetic risk factors contributed to comorbid major depressive disorder and alcohol dependence.

“The National Comorbidity Study linked [alcohol dependence] to 3.7-fold higher odds of experiencing a major depressive episode in the prior year. In the 2012-2013 National Epidemiologic Survey on Alcoholism and Related Conditions, individuals with a lifetime diagnosis of [major depressive disorder] had a 1.3-fold increased risk of an alcohol use disorder,” Allan M. Andersen, MD, of University of Iowa, Iowa City, and colleagues wrote.