Depression often co-occurs with other mental health disorders — a phenomenon known as a comorbidity.
Depression is a serious mental health disorder that can be quite debilitating on its own.
If you have depression plus another mental health condition, such as anxiety or substance use disorder (SUD), those conditions are considered “comorbid” and can be more complex and difficult to treat.
It’s not uncommon for someone to receive a diagnosis of major depressive disorder (MDD) along with another mental health condition.
Some of the most common comorbid diagnoses with depression include:
- anxiety disorders, such as generalized anxiety disorder (GAD) or panic disorder
- obsessive-compulsive disorder (OCD)
- post-traumatic stress disorder (PTSD)
- greater symptom severity
- poorer quality of life and less social support
- suicidal ideation/suicide
- poorer outlook
- less response to treatment
- a greater demand on the healthcare sector
The National Alliance of Mental Health reports that comorbid anxiety and depression tend to be significantly harder to treat than either of these conditions on their own.
There are a few theories as to why these two conditions often occur together:
- They have similar biological mechanisms, causing them to frequently appear together.
- They have overlapping symptoms (such as worry or sleep problems), causing people to meet criteria for both disorders.
- They tend to present at the same time when people are under stress.
When anxiety shows up with depression, it can involve just a few symptoms (feeling tense or short of breath) or a full-blown anxiety disorder, such as GAD and panic disorder.
Symptoms of anxiety may include:
- poor concentration
- feelings of restlessness or being on edge
- easily tired
- feeling irritable
- feeling out of control
- sense of impending doom
- rapid heart rate
- trembling or shaking
- muscle tension
- sleep difficulties
Nearly one-third of people with MDD also have SUD. SUD is a complex condition characterized by the recurrent use of alcohol, drugs, or both despite the harmful health and life consequences.
People with both depression and SUD have a greater risk of suicide, worse social and personal impairment, and a greater likelihood of other psychiatric conditions.
SUD may involve one of the following substances:
- sedatives, hypnotics (sleep-inducing drugs), or anxiolytics (anti-anxiety drugs)
- stimulants (amphetamines or cocaine)
- opioids (heroin or prescription drugs)
- hallucinogens (including LSD and phencyclidine)
OCD is a mental health disorder associated with recurrent cycles of unwanted obsessions and compulsions.
There’s a strong link between OCD and depression. Up to
Research shows that people with severe depression often have obsessive-compulsive symptoms. Some evidence suggests that depressive symptoms are more strongly related to the obsessive rather than compulsive symptoms of OCD.
PTSD is a psychiatric disorder that can occur if you’ve experienced or witnessed a traumatic event or a series of traumatic events.
There’s also some symptom overlap, making it difficult to tease apart the two disorders.
Symptoms that occur in both disorders include:
- anhedonia (reduced ability to experience pleasure)
- sleep disturbance
- concentration difficulties
There are several risk factors that can increase your likelihood of comorbid depression, including:
- Genetics: A family history of depression can increase your risk of developing comorbid depression.
- Chronic stress: Chronic personal stress, whether related to work, finances, or relationships, can increase your risk of developing depression.
- Previous episodes of depression: A history of depression increases your chances of having it again.
- Chronic medical conditions: Physical conditions, such as heart disease, stroke, cancer, and diabetes, can increase your risk of developing depression.
- Substance misuse: Substance misuse, including alcohol and drug addiction, is a common risk factor for depression.
- Traumatic life events: Exposure to traumatic life events can increase your risk of developing depression.
- Lack of social support: A lack of social support, such as having few friends, family, or other support networks, can increase your risk of depression.
Most studies have focused on people with only one mental health condition, and treatments are then developed based on this research. So, while there are a lot of research-backed treatments for mental health disorders, that’s not necessarily the case for comorbid disorders.
Still, treatment for depression typically involves a combination of medications and psychotherapy.
Medication commonly used to treat depression include:
- selective serotonin reuptake inhibitors (SSRIs)
- serotonin-noradrenaline reuptake inhibitors (SNRIs)
- tricyclic antidepressants (TCAs)
Psychotherapy, such as cognitive behavioral therapy (CBT), can be highly effective in treating comorbid depression. CBT can help you identify and change negative thought patterns and behaviors that may be contributing to depression.
How to treat depression and anxiety
When depression and anxiety co-occur, it’s often more difficult to treat because the symptoms tend to be more intense and persistent when they’re together.
Clinicians may need to add one treatment on top of another to make sure that the symptoms of both disorders are responding. For instance, if antidepressants are helping improve your mood, but not your anxiety, a doctor or healthcare professional might add another medication or CBT to your treatment plan.
Though treatment may be more complex when dealing with comorbidity, healing is possible.
It’s common to have more than one mental health disorder, a phenomenon known as comorbidity.
If you have depression and another disorder, such as anxiety or substance dependence, don’t hesitate to reach out to a mental health professional who can help you get started on the right treatment for you.