Understanding the Differences: Illness Anxiety Disorder vs. Somatic Symptom Disorder

This article will delve into and clarify the distinctions between Illness Anxiety Disorder (IAD) and Somatic Symptom Disorder (SSD). 


Somatic symptom disorder is the overarching category under which falls illness anxiety disorder. All of these disorders share the common feature of having prominent somatic symptoms and/or illness anxiety that causes significant impairment in daily life and distress.

The majority of people who struggle with these disorders do so in primary care or medical settings. So, what is the difference between somatic symptom disorder and illness anxiety disorder? This article will highlight the key differences between illness anxiety disorder versus somatic symptom disorder.

woman Illness Anxiety Disorder

Defining Illness Anxiety Disorder and Somatic Symptom Disorder

Somatic is defined as something related to the body, but something that starts in the mind which means a way of thinking about your body. 

Somatic symptom disorder is a category and the primary mental health condition where an individual who has a serious illness is dangerously preoccupied with thoughts and feelings related to their symptoms and how serious those symptoms might be.

With somatic symptom disorder vs. illness anxiety disorder, illness anxiety disorder doesn’t have the same persistently high anxiety over symptoms or disproportionate thoughts about how serious your symptoms are but rather a preoccupation with developing a health issue.

-Prevalence for illness anxiety disorder vs somatic symptom disorder 

Scientists are unclear about the prevalence of somatic symptom disorder. However, some research has found that across North America and Europe, the prevalence in adults is around 4%.

Illness anxiety disorder has a prevalence across countries like the United States between 1.3% and 10%.

-Risk factors: somatic symptom disorder vs illness anxiety disorder

Somebody with a neurotic personality trait is at a higher risk of developing somatic symptom disorder. It’s not uncommon for anxiety and depression to coexist and exacerbate the symptoms of somatic symptom disorder.

Other risk factors include environmental. Somatic symptom disorder more frequently appears in individuals who have struggled with low socioeconomic status, undergone stress, have low education, and experienced childhood abuse, particularly sexual abuse.

Illness anxiety disorder is often precipitated by a major stressful event or a serious but ultimately benign threat to health. Other environmental risk factors include:

  1. A childhood illness
  2. History of childhood abuse
  3. A serious illness in a parent
  4. The death of a seriously ill parent during childhood
psychological help

Clinical presentation

With illness anxiety disorder vs somatic symptom disorder, the clinical presentation is slightly different. 

Somatic symptom disorder diagnostic criteria

In order to receive a diagnosis of somatic symptom disorder, an individual must exhibit the following:

  1. One or more symptoms that cause significant disruption to daily life or distress
  2. Excessive thoughts, behaviors, and emotions related to somatic symptoms or health concerns manifested by one of the following:
    1.  disproportionate and recurring thoughts about the seriousness of the symptoms
    2.  persistently high anxiety levels regarding health or symptoms
    3.  excessive time and energy devoted
  3. The state of being symptomatic must be persistent for more than six months even if any one of the somatic symptoms does not remain continuous throughout that time frame

Illness anxiety disorder diagnostic criteria

In order to receive a diagnosis of illness anxiety disorder, an individual must exhibit the following:

  1. Complete preoccupation with acquiring or having a very serious illness
  2. No somatic symptoms or mild somatic symptoms at best
  3. A high level of anxiety regarding health, being easily alarmed about health status, excessively checking health-related behaviors such as looking for signs of illness over the body or avoiding doctor’s appointments in case they find an illness preoccupation with an illness that has lasted at least six months preoccupation with an illness that is not better explained by any other condition

-Diagnostic challenges for illness anxiety disorder versus somatic symptom disorder 

There can be diagnostic challenges to getting help because there are several other conditions that might have some of the same symptoms. Moreover, for both somatic symptom disorder and illness anxiety disorder, a professional has to rule out any other psychological factors that could affect a medical condition, any other medical conditions, and any other mental health disorders, including:

  1.  panic disorder
  2.  generalized anxiety disorder
  3.  depressive disorders
  4.  conversion disorder
  5.  delusion disorder
  6.  body dysmorphic disorder
  7.  obsessive-compulsive disorder
  8.  facetious disorder and malingering
  9.  adjustment disorders
  10.  psychotic disorders
Somatic symptom disorder treatment services

-Impact on Daily Life

The biggest difference between somatic symptom disorder and illness anxiety disorder is that someone with somatic symptom disorder actually has a health problem, but they become preoccupied with anxiety and concern over the symptoms related to that health problem, even if it is something minor. By comparison, someone with an illness anxiety disorder doesn’t necessarily have a health problem, but they are terrified of getting one. Illness anxiety disorder used to be referred to as a hypochondriac.

The impact on daily life can look somewhat similar: 

Marcus has severe pain localized to his back and general fatigue. He spends all of his time distressed about the pain and the fatigue, looking up information online, and going to appointments. Whenever he talks to friends or family, all he talks about is his health and his symptoms. It is getting so bad that Marcus can barely get out of bed, and he’s experiencing radiating nerve pain in his back. Every day he checks his body for any potential issues or new symptoms.

Marcus has gone to the doctor who has found no source of the pain and has assured him that most of it is anxiety and stress-related, and if he were to move more, Marcus wouldn’t necessarily have the same back pain and he wouldn’t have the same fatigue. But Marcus doesn’t care. He continues to complain about the pain and doesn’t believe any of the doctors, even though he has seen six of them. His concerns are never alleviated, no matter how many doctors he sees. 

Marcus struggles with somatic symptom disorder.

Tina would have previously been called a hypochondriac. She is constantly worried about getting sick. Anytime there is something wrong with her body, such as a mild ache from twisting or sitting, dull pain, or fatigue, she becomes overly anxious and feels that any type of physical sign or symptom means she has a serious condition. Even something as simple as being a little dizzy after walking around her property or belching after a meal is something she views with substantial anxiety as a potentially harmful disease. 

Most of the time she avoids any activity that she thinks could jeopardize her health which prevents her from exercising at all. She’s also terrified of catching diseases from other people, so she avoids visiting any sick friends or family members. Even though her doctors have reassured her that she doesn’t have any symptoms, she doesn’t believe them, and she repeatedly checks her body for continual signs of illness.

Tina has an illness anxiety disorder.

Treatment Approaches

Talk therapy is one of the most effective treatments for somatic symptom disorder and illness anxiety disorder. It can help individuals change their thought patterns and their behaviors. It can also help them learn ways to cope with symptoms like pain and improve daily function by managing stress. In some cases, antidepressants or anti-anxiety medications might be prescribed for secondary symptoms. 

In both conditions, self-care strategies like relaxation techniques and stress management can be particularly effective in conjunction with talk therapy.

Summing Up

With somatic symptom disorder vs. illness anxiety disorder, there are key differences. The most important thing despite any differences between illness anxiety disorder vs. somatic symptom disorder is that you get an early diagnosis and find appropriate treatment. If you or someone you know may be experiencing symptoms of either condition, it’s important that you seek professional help.