Seasonal affective disorder, commonly known as SAD, is a condition that occurs annually, at the same time of year during a particular season. For most people, SAD occurs in late fall and continues through early winter. SAD is actually not a separate disorder, it is a specifier of major depressive disorder. The American Psychiatric Association has indicated that a patient must have the characteristics of major depressive disorder and seasonal affective disorder to confirm a diagnosis.
Major Depressive Disorder: Depressive Episode Characteristics
The primary characteristic for major depressive disorder is the presence of five or more depressive symptoms occurring nearly every day over the course of two weeks or more. These symptoms must be behaviors that are markedly different than the patient's typical behavior, mood or affect. Examples of depressive symptoms include depressed mood or irritability, diminished interest in pleasurable activities, significant weight loss or weight gain, insomnia or hypersomnia, psychomotor agitation or retardation, fatigue, feelings of worthlessness, excessive inappropriate guilt, diminished ability to concentrate or make a decision, recurrent thoughts of death or suicidal ideation without a plan.
Major Depressive Disorder: External Characteristics
To confirm a diagnosis of major depressive disorder and thereby, the characteristics of seasonal affective disorder, it must be determined that the patient's symptoms are not symptoms of another medical illness or condition, caused by the alcohol or substance use and cannot be attributed as a symptom of bereavement.
Seasonal Affective Disorder: Occurrence of Depressive Episodes
The primary characteristic of SAD is the occurrence of depressive episodes. The depressive episodes must occur regularly at a particular time of year, each year. Patients must also notice a remission or change in mood at a particular time of year, each year. The patient must experience two or more major depressive episodes in the previous two years and the seasonal episodes must outnumber the nonseasonal episodes. For example, Jane has seasonal affective disorder. Jane notices that she feels depressed and less motivated every November and feels this way until April, when spring starts. She has felt this way every year for the past four years. She does feel sad at other times of the year but they are more sporadic and do not last for an extended amount of time.
Seasonal Affective Disorder: Characteristic Symptoms
The identified symptoms of seasonal affective disorder are similar to those of major depressive disorder. Depressed feelings, hopelessness, anxiety, difficulty concentrating, social withdrawal, loss of energy, oversleeping, loss of interest in pleasurable activities, appetite changes, weight loss or weight gain are among the symptoms. However, these symptoms always occur during the patient's affected season and dissipate when that season is over.
References
- American Academy of Family Physicians: Seasonal Affective Disorder
- Mayo Clinic: Seasonal Affective Disorder
- American Psychiatric Association: Diagnostic and Statistical Manual, Fourth Edition
