Insomnia and Depression: Interconnected Symptoms

The co-occurrence of insomnia and depression has been noted since Greek physicians described it in the anatomy of melancholia. Insomnia is commonly associated with depression, with approximately 90% of patients with major depressive disorder experiencing sleep complaints. Insomnia can persist even after depression remits. Insomnia disorder can present as a depressive episode due to overlapping symptoms. Insomnia is a risk factor for the onset of depression, with symptoms like difficulty initiating or maintaining sleep, early morning awakenings, low energy levels, attention and concentration changes, irritability, and mood changes being common.