Subsyndromal Symptomatic Depression

SSD affects people similarly to major depression

Sad girl lying in bed
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Subsyndromal symptomatic depression (SSD) is a term that indicates that a person's depression symptoms don't quite meet the criteria for a diagnosis of a major depressive episode. It's actually quite common.

Understanding Subsyndromal Symptomatic Depression

The criteria for SSD is that you have two or more symptoms of depression that aren't severe enough for a depression diagnosis. Like depression, the symptoms must have been present for two weeks or more and have caused social dysfunction, such as isolation, withdrawal, or behavior changes.

It's thought that subsyndromal symptomatic depression symptoms may be a risk factor for developing clinically significant major depressive disorder in the future.

Depressive Symptoms

Symptoms that develop on a daily or almost daily basis and that may occur in both SSD and major depression are:

  • Feeling sad or depressed 
  • A significant change in appetite and/or weight
  • Needing too much or not getting enough sleep
  • Either being noticeably restless or being run down
  • Not enjoying the activities you once did
  • Feeling wiped out or fatigued
  • Feeling hopeless, worthless, and/or guilty
  • Having trouble concentrating or making decisions
  • Having thoughts of death or suicide or suicidal behavior

The difference in these symptoms is that with depression, you must have at least five of the symptoms to be diagnosed. With SSD, you only experience two to four of these symptoms.

Why SSD Is Significant

Many people have depressive symptoms that don't quite meet the criteria for being diagnosed with major depression.

Recent studies show that subsyndromal symptomatic depression has just as much of an impact on function and has the same risk factors as major depression. Subsyndromal depression also has the same negative effects on overall health as major depression does.

Some researchers believe that there is a spectrum of depression, from fewer symptoms to symptoms that don't last long to severe symptoms, and that all depressive episodes, despite their severity, have similar adverse effects on individuals.

One study that used a broad sampling of people from a variety of countries across the globe showed that subsyndromal depression seems to be quite a significant problem worldwide. Because of its detrimental effects, the study concluded that more research needs to be done on subtypes of depressive disorder. The researchers also believe that mental health professionals should take note of even minimal depressive symptoms since they are harmful to a person's overall health.

Mild Symptoms Should Be Noted

We all know early intervention is the key to successful treatment, so if mental health professionals note even mild depressive symptoms, treatment may very well be indicated so that symptoms do not become worse. With studies showing that even mild symptoms are fairly disabling, it's important to help people with subsyndromal symptomatic depression and other depressive subthreshold disorders function at their best.

Potential Challenges in Diagnosing Depression 

The same study notes that clinicians are very good at ruling out depression, but not nearly as successful at diagnosing it. This could be due to the thresholds that are set in the Diagnostic and Statistical Manual (DSM) and the difficulties in assessing the significance of depressive symptoms.

There is a challenge in identifying people who are close to the threshold of depression set out in the DSM. The researchers of this study came to the conclusion that further research is needed and that SSD should be classified on its own and potentially treated similarly to major depression.


Ayuso-Mateos JL, Nuevo R, Verdes E, Naidoo N, Chatterji S. From Depressive Symptoms to Depressive Disorders: the Relevance of ThresholdsThe British Journal of Psychiatry. May 2010;196(5):365-71. doi:10.1192/bjp.bp.109.071191.

Pietrzak RH, Kinley J, Afifi TO, Enns MW. Subsyndromal Depression in the United States: Prevalence, Course, and Risk for Incident Psychiatric OutcomesPsychological Medicine. July 2013;43(7):1401-1414. doi:10.1017/S0033291712002309.

Yi Z, Fang Y. Are Subsyndromal Symptomatic Depression and Major Depressive Disorder Distinct Disorders? Shanghai Archives of Psychiatry. 2012;24(5):286-287. doi:10.3969/j.issn.1002-0829.2012.05.006.