By Dr. David Woo - May 8, 2023

Obsessive-compulsive disorder (OCD) and depression are distinct mental disorders that, despite their differences, can be connected in some individuals. Fortunately, this also means that certain treatments can be effective in treating both. In this article, we’ll take a look at the similarities and differences between the two.

OCD is classified as an anxiety disorder while depression is a mood disorder. Despite this, there is a high rate of comorbidity (suffering from both diseases at the same time). Research shows that approximately 33% of OCD patients have depression (1), while two-thirds will experience at least one major depressive episode during their lifetime(2).

At first glance, the two conditions do not appear to be closely related, as they manifest through very different symptoms.

• Symptoms of OCD include persistent worries and intrusive thoughts. The patient feels compelled to control these anxious thoughts via rituals and repetitive, predictable behaviors.
• Depression symptoms include overpowering feelings of sadness and hopelessness. The patient experiences a loss of interest in previously enjoyable activities and aspects of life.

Both disorders can have a serious impact on an individual’s professional, family, and social life.

How Are OCD and Depression Similar?

Our thoughts and feelings are generated and regulated by electrochemical activity in the brain. Mental disorders are often caused by irregularities or interruptions in this process. For example, both OCD and depression are associated with an imbalance of serotonin, a chemical responsible for communication between nerve cells. Our brain chemistry is also partially determined by genetics, which is why OCD and depression often have a common genetic diathesis; that is, caused by the same genetic traits(3). 

People with OCD may have a predisposition toward depression because they already lack a balanced level of serotonin in their brain. And while OCD itself does not cause depression, it’s more common for someone with OCD to later develop depression than for someone with depression to develop OCD. This suggests that the stress of living with OCD, including anxiety or feelings of discrimination, may trigger depressive symptoms.

How TMS Can Help Both OCD and Depression

The connection between depression and OCD can be helpful when it comes to treating either disorder or the co-occurrence of both. People with OCD and depression often have trouble adhering to a long-term schedule, which makes it difficult to commit to therapy or medication. The latter is also often ineffective or intolerable due to uncomfortable side effects. However, there is another treatment that has proven effective even in cases where medication has failed.

Transcranial magnetic stimulation (TMS) is a non-invasive, non-pharmaceutical treatment method for mental health disorders that uses a headpiece to target particular brain areas with subtle, barely noticeable magnetic pulses. This helps regulate the electrochemical imbalances in the brain related to OCD and depression. TMS is FDA-approved for treating both disorders, as well as others such as anxiety and ADHD.

If you think you are experiencing symptoms of OCD and/or depression, it’s important to seek professional advice and treatment as early as possible. Madison Avenue TMS & Psychiatry offers talk therapy and TMS for the treatment of OCD, depression, and other conditions. To make an appointment for consultation or treatment, contact us online or call (212) 731-2033.

1. Overbeek T, Schruers K, Vermetten E, Griez E. Comorbidity of obsessive-compulsive disorder and depression: prevalence, symptom severity, and treatment effect. J Clin Psychiatry. 2002;63(12):1106-12. Link. Accessed April 2, 2023.
2. Pallanti S, Grassi G, Sarrecchia ED, Cantisani A, Pellegrini M. Obsessive-compulsive disorder comorbidity: clinical assessment and therapeutic implications. Front Psychiatry. 2011;2:70. Link. Accessed April 2, 2023.
3. Bolhuis K, McAdams TA, Monzani B, Gregory AM, Mataix-Cols D, Stringaris A, Eley TC. Aetiological overlap between obsessive-compulsive and depressive symptoms: a longitudinal twin study in adolescents and adults. Psychol Med. 2014;44(7):1439-49. Link. Accessed April 2, 2023.

Dr. David Woo

Dr. Woo has been seeing patients in private practice since 2002, always with the goals of combining evidence-based medicine with psychodynamic psychotherapy and collaborating with other mental health professionals to ensure the best possible outcomes for his patients. He has been certified to administer TMS at his practice since 2017. His greatest clinical interests include helping patients suffering from depression, anxiety, and obsessive compulsive disorder.