An Overview of the DSM Criteria Employed For the Diagnosis of Major Depressive Disorder
Although only a licensed psychiatrist, psychologist or general practitioner can properly diagnose a major depression, people need to be fully informed about the methods of diagnosis used by doctors, which are known as DSM criteria for major depressive disorder. There are currently two systems of criteria used in the world; ICD-10 criteria system is described by the World Health Organization and it is used only in the European countries and DSM-IV-TR criteria system, which is described by the American Psychiatric Association and it is used in the United States and in the rest of the world.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) designates two predominant symptoms – depressed mood and anhedonia (the inability to find pleasure in enjoyable activities) – while ICD-10 system, in addition to these two, also considers decreased energy levels as a symptom of major depression disorder. Therefore, according to the DSM criteria system, in order to diagnose a single or recurrent major depressive episode, at least one of the two main symptoms must be present, which is either depressed mood or loss of pleasure/interest.
DSM criteria for major depressive disorder (MDD) marks out a total of 9 symptoms. The patient must have at least 5 of the following symptoms for a period of 2 weeks, in order to be diagnosed with a single or recurrent major depressive episode.
- Significantly depressed mood almost every day (feeling low/sad/void; teens may experience an irritable mood);
- Particularly reduced pleasure or interest in approximately all enjoyable daily activities;
- Significant sleep disturbances – either insomnia or hypersomnia;
- Marked weight disturbances – more than 5% either weight loss or weight gain and/or increase or decrease in appetite;
- Marked fatigue and/or loss of energy throughout the day;
- Psychomotor agitation ( an increase in activity due to mental tension) and/or retardation (a decrease in physical activity);
- Experiencing feelings of excessive or inadequate guilt and worthlessness;
- Decreased memory and focus and the inability to make a decision;
- Recurrent thoughts of suicide and death, with or without a suicide attempt and/or a specific plan to commit suicide.
These DSM criteria do not take into consideration the consequences of bereavement, which is a normal response to the death of a beloved person.
If the above mentioned criteria, employed in the diagnosis of major depressive episodes, are not met by the manifestation of a depressive episode, then the diagnosis of such an episode is placed under the category “Depressive Disorder Not Otherwise Specified (DD-NOS), which includes recurrent brief disorder and minor depressive disorder.
DSM-IV-TR criteria classifies major depressive disorder(MDD) as a mood disorder. MDD, also known as unipolar disorder/depression or major/clinical depression is a mental disorder without symptoms of mania ( as opposed to manic-depressive disorder known as bipolar disorder), whose cluster of symptoms ( called major depressive syndrome) include low mood and self-esteem, insomnia (80% of the MDD cases), poor focus and memory and loss of interest in otherwise normally pleasant daily activities (anhedonia). Recently, doctors take into consideration motivational anhedonia, which refers to the lack of desire or motivation to engage into enjoyable activities, in addition to consummatory anhedonia (enjoying the agreeable/pleasant activities).
The diagnosis of MDD is based on the examination of the mental status of the patient by the qualified physician, on the self-reported behaviour and experiences of the patient and on those reported by his relatives and friends (all according to the DSM criteria), his pertinent medical history, psychiatric co-morbidity (presence of other psychiatric conditions such as recurrent anxiety episodes, post-traumatic stress disorder and pain, attention-deficit hyperactivity disorder as well as the presence of cardiovascular disorders) and current drug abuse.
The two-question screen of the medical interview include:
- Have you experienced little interest or pleasure in normally enjoyable activities over the past month?
- Have you experienced feelings of hopelessness or feeling down or depressed over the past month?
The causes of MDD are biological, psychological, social, evolutionary and drug-induced. A CT scan and cognitive testing are used to differentiate MDD from Alzheimer s disease and other brain pathologies, which have the same symptoms as MDD. A single or recurrent major depressive disorder is rated mild, moderate or severe, the latter being considered psychotic depression.
There are 5 subtypes of MDD which are known as specifiers, as follows:
- Postpartum depression – represents the severe disabling depression experienced by women who have recently given birth. DSM criteria require that onset of this subtype of depression should take place within one month of delivery, so as to qualify as such. 10-15% of the new mothers experience this and it typically lasts up to three months.
- Melancholic depression – is different from grief/loss of a loved person and it is typically characterized by lack of mood response to positive stimuli or events and the inability to find positive and pleasant activities enjoyable, in addition to marked weight/appetite loss, psychomotor agitation or retardation, excessive guilt, early morning awakening and a severely low mood in the morning.
- Catatonic depression – it represents a severe, yet rare subtype of depression which involves motor disturbances – the patient is dumbfounded, does not speak and either remains immovable or displays purposeless and uncanny movements. These symptoms are also present in mania and schizophrenia.
- Atypical depression – is typically characterized by reactivity to enjoyable stimuli or events (known as paradoxical anhedonia), mood positivity, marked weight gain and an increase in appetite, excessive sleep, heaviness in the limbs, as well as marked social impairment especially following rejection in interpersonal relationships.
- Seasonal affective disorder – involves the presence of major depressive episodes typically in the fall or winter and which clear up in the spring. The diagnosis takes into account the occurrence of at least two such episodes in colder seasons alone, over a period of two years.
Knowing the DSM criteria for major depressive disorder is a useful piece of information especially for people who are confronting with a recurrent depressed mood and who cannot find pleasure in daily activities which used to be enjoyable in the past.