Depression and Co-Occurring Mental Health Conditions

Depression can, and often does, have a big impact on your life. From the amount of energy you have right to the level of enjoyment you get out of spending time with loved ones, it can eat at your life in many different ways.

But have you ever noticed other symptoms creeping into your life that don’t relate to depression? Could it be another mental health condition? In short, yes. People with depression often struggle with other mental health conditions, such as anxiety, post-traumatic stress disorder, and attention-deficit hyperactivity disorder.

But how exactly does depression affect mental health? And how does it link to other mental health conditions? Below, we explore the link between depression and other mental health conditions, including:

Anxiety
Bipolar disorder
Schizophrenia
Obsessive-compulsive disorder
Eating disorders
Post-traumatic stress disorder
Attention-deficit hyperactivity disorder
Personality disorders
Chronic illness

How Does Depression Affect Mental Health?

Depression is a mental health condition that, in any form, tends to affect your mental health in significant ways. Mild depression can make everyday tasks just that little bit harder to do and can affect how you feel about yourself. Severe depression, on the other hand, can make you feel deeply sad, alone, and hopeless. In some cases, depression can also trigger thoughts of harming yourself, or behaviors to do so.

There are many different types of depression, each affecting mental health in different ways. For example, those with persistent depressive disorder have a continuous low mood that doesn’t shift. Whereas, people with bipolar disorder may feel extremely energized one day and struggle with high anxiety and low mood the next. Different still is seasonal affective disorder, which only impacts someone for a season (usually winter), and then eases with the changing weather.

However, regardless of which form of depression you’re struggling with, it can take a negative toll on your overall health and emotional well-being. Alongside this, depression can lead to sleep disturbances, appetite changes, fatigue, and poor concentration, which can worsen its effect on your mental health.¹

What Is the Relationship Between Mental Health and Depression?

As depression is a diagnosable mental health disorder, it has an intimate relationship with mental health. If you’re struggling with depression, you’ll feel more mentally unwell. What’s more, many mental health conditions often occur at the same time as depression. In fact, at least one-third of people with major depressive disorder also have another psychiatric condition.²

The question you may be asking right now is “Why?” And how does depression link with specific mental health conditions like anxiety, bipolar disorder, schizophrenia, and OCD? Below, we break down some of the mental health conditions that most commonly co-occur with depression.

Depression and Anxiety

Depression and anxiety often occur together. According to research, those with depression are more likely than not to have a co-occurring anxiety disorder – with two-thirds of people receiving a diagnosis for both conditions.³

When someone has both anxiety and depression, they experience the symptoms of both conditions. In some cases, this can lead to severe and long-lasting symptoms and potentially increase a person’s suicide risk.³

Depression and Bipolar Disorder

One of the key symptoms of bipolar is depressive episodes. Those with bipolar tend to alternate between periods of extreme elation and euphoria (known as manic episodes) and periods of low mood and energy (known as depressive episodes).

However, the extent to which depressive episodes affect a person with bipolar depends on which type of bipolar they have: Bipolar I or bipolar II. Those with bipolar I tend to have longer manic episodes followed by shorter depressive episodes. However, these depressive episodes still have symptoms of mania, such as elevated energy. In contrast, bipolar II involves longer periods of depression and less intense manic episodes.⁴

Depression and Schizophrenia

Schizophrenia is a long-term mental illness that can involve hallucinations, such as seeing or hearing things that aren’t happening, and delusions – beliefs that aren’t real. Studies suggest that approximately 19% of people diagnosed with schizophrenia experience symptoms of depression. Therefore, these two conditions also often coexist.⁵

It’s also possible to have depression with psychotic features, also known as psychotic depression. Those with psychotic depression tend to experience delusions and hallucinations, as well as the typical symptoms of major depressive disorder.

Research shows that prescribed medications, including quetiapine, olanzapine, and risperidone, can reduce the occurrence of depression in those with schizophrenia.⁵

Depression and Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a mental health condition that involves a person showing compulsive or repetitive behaviors and obsessive thoughts. For example, a person with OCD may worry that something bad will happen if they don’t perform a behavior, such as switching a light on and off a certain number of times.

There appears to be a strong overlap between depression and OCD. Obsessional thoughts can increase the risk of depression symptoms. Both OCD and depression are also connected to negative emotions and difficulties with concentration.⁶

Depression and Eating Disorders

Research has shown that up to 54% of those with eating disorders have a co-occurring mood disorder like depression.⁷Therefore, depression is relatively common in those who struggle with disordered eating.

Unfortunately, research shows that having depression alongside an eating disorder can increase the severity of eating disorder symptoms. What’s more, depression may make it more difficult for someone to recover from an eating disorder.⁸

Depression and PTSD

PTSD (short for post-traumatic stress disorder) is a common mental health condition that may arise after trauma, such as a serious injury, threatened death, or sexual violence.

Exposure to trauma can increase a person’s risk of experiencing depressive symptoms. So, it’s not surprising then that there’s a high comorbidity rate between depression and PTSD. Approximately half of people with PTSD also have depression.⁹

Depression and ADHD

Attention-deficit hyperactivity disorder (ADHD) is a common developmental disorder that can lead to restlessness, difficulties concentrating, and impulsive behavior. ADHD tends to be present from an early age but often becomes more noticeable in school years. While research can’t point to a direct cause of ADHD, evidence suggests that there may be differences in the brain structure and function of people with ADHD compared to those without.

Scientists have found that having ADHD during childhood increases the risk of recurrent depression later in life. Genetics associated with ADHD can also make people vulnerable to depression symptoms.¹⁰

Depression and Personality Disorders

Personality disorders are mental health conditions that affect how a person feels, thinks, and behaves, as well as the way they relate to others. The term “personality disorder” groups several mental health conditions together. Some of the most common personality disorders are:

Antisocial personality disorder
Obsessive-compulsive personality disorder
Borderline personality disorder
Narcissistic personality disorder.

However, there are actually 10 forms of personality disorders. So, these are just a few examples. Research has found a strong overlap between depression and personality disorders. Borderline personality disorder and obsessive-compulsive personality disorder appear to be particularly common in those with depression.¹¹

Depression and Chronic Illness

While chronic illness isn’t necessarily classified as “mental health,” it’s important to share the link here. Why? Because chronic illness can have a highly detrimental impact on our mental health, so the two are closely linked.

Studies don’t show a direct link between depression and chronic illness, per se. However, this is what the research tells us:

Depression is associated with risky healthy behaviors, which can in turn increase the risk of chronic health conditions.
Complications associated with medical conditions can lead to depression.
Depression can lead to a worse prognosis in people with chronic health conditions because it can interfere with proper self-care and treatment compliance.¹²

So, while depression may not lead to chronic illness (or there’s no evidence to suggest so, at least), it could make life more difficult for those with an existing chronic illness. Plus, those with a chronic illness may be at a higher risk of depression, especially if they face complications with their illness.

Treatment for Depression and Co-Occurring Mental Health Conditions

While depression and co-occurring mental health conditions may come with many difficulties, it’s important to remember that recovery is possible. What’s more, many treatment options are available to help you cope and reduce your symptoms. Let’s explore some of the key treatment methods for depression and co-occurring conditions:

Cognitive Behavioral Therapy (CBT)

CBT focuses on identifying and changing negative thought patterns and behaviors that contribute to depression and other mental health conditions. Research shows that CBT can be highly effective for those struggling with depression, anxiety, OCD, personality disorders, and more. At Mission Connection, we offer individualized CBT services (both in person and online) to suit both you and your unique combination of mental health conditions.

Interpersonal Therapy (IPT)

IPT focuses on improving communication and relationship skills and addressing any relationship issues that may be worsening depression symptoms. IPT can be particularly effective for those facing depression after losing a loved one, experiencing a life transition, or after a relationship breakdown. At Mission Connection, we have specialized IPT therapists who can support you in addressing your depression symptoms and relationship difficulties.

Transcranial Stimulation Therapy (TMS)

TMS is a non-invasive brain stimulation therapy that uses magnetic pulses to stimulate the areas of the brain that play a role in regulating mood. TMS appears to be effective for treatment-resistant depression, and may also help those with anxiety and OCD. Our team at Mission Connection can provide information on TMS, assist with insurance, and offer support throughout the treatment process.

Trauma-Focused Therapy

This form of therapy addresses the impact of trauma on mental health in general, which means it can help people process their traumatic experiences and build coping strategies. As such, this can help to heal from PTSD and alleviate symptoms of trauma-related depression and anxiety.

Emotion Regulation Therapy

Emotion regulation is the process of managing your difficult emotions. Therefore, in emotion regulation therapy, your therapist will help you develop this skill, which can prove beneficial for co-occurring depression and anxiety, as it may reduce rumination and improve quality of life.¹³

It’s important to note that treatment should be integrated, addressing both conditions at once. The treatment modalities listed above can be particularly effective for co-occurring conditions.

Reach Out for Depression Support Today

If you’re struggling with depression and co-occurring mental health conditions, know that you don’t have to manage these alone. At Mission Connection, we offer a range of treatment approaches and programs to suit you and help you manage your symptoms.

If your symptoms are severe and affecting your day-to-day life, making it difficult to function, we offer residential treatment programs in California, Virginia, and Washington. However, if your symptoms are manageable and you’d like to visit for support services instead, we also offer outpatient programs.

And if you’re feeling overwhelmed and unsure which program is right for you, that’s okay, too. We can help. Reach out to us and we can guide you through the process of choosing the program that’s right for you.

Get in contact at 866-338-4958, or get started here.

References

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National Institute of Mental Health. (2025). Bipolar disorder. https://www.nimh.nih.gov/health/topics/bipolar-disorder
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