The signs of depression usually develop over days to weeks. A prodromal period that may include anxiety symptoms and mild depressive symptoms may last for weeks to months before the onset of a full depressive episode. An untreated depressive episode typically lasts 4 months or longer, regardless of age at onset. In a majority of cases, there is complete remission of symptoms, and functioning returns to the premorbid level. In a significant proportion of cases (20-30%), some depressive symptoms insufficient to meet full criteria for a major depressive episode may persist for months to years and may be associated with some disability or distress. In some individuals (5-10%), the full criteria for a major depressive episode continue to be met for 2 or more years.1
The overall symptoms associated with depression include tearfulness, irritability, brooding, obsessive thoughts, anxiety, guilt, excessive worry over physical health, complaints of pain, persistent aches or pains, headaches, cramps or digestive problems that do not ease, even with treatment.2 Some individuals note difficulty in intimate relationships, less satisfying social interactions, or difficulties in sexual functioning. There may be marital, occupational, and academic problems, alcohol or other substance abuse, or increased utilization of medical services as a result of depression. The most serious consequence of depression is attempted or completed suicide.
The warning signs and symptoms of depression are key to accurately diagnosing the condition which is done by a clinical psychologist and/or psychiatrist. It is important to observe and note any symptoms over a period of at least two weeks time.2
To read more on which specific depression symptoms lead to a diagnosis of depression, click on Depression Diagnosis.
Differences in Age
The rate of depression does vary with age. The onset of depression increases dramatically during adolescence with rates being highest for individuals aged between 25 and 45. The onset of an individual’s first depressive episode most often occurs in their 30’s to 40’s. Most typically, this initial episode is experienced in an individual's mid-twenties with 50% of depressed individuals experiencing this onset before the age of 40. Reported rates are lower for individuals over 65 years old 3,4 but it is speculated that this age group is the largest to suffer from depression; This is probably due to the fact that depression often goes undetected or undiagnosed in the older population.12
Regarding symptomatology and aging, elderly adults may experience depression with more prominent cognitive symptoms (e.g., disorientation, memory loss, and distractibility). Epidemiological evidence suggests that there is a fourfold increase in death rates in individuals with major depressive disorder who are over the age of 55. Individuals with major depressive disorder admitted to nursing homes may have a markedly increased likelihood of death in the first year. Among individuals seen in general medical settings, those with major depressive disorder have more pain and physical illness and decreased physical, social, and role functioning.
Read more on Childhood Depression
Read more on Adolescent Depression
Read more on Geriatric Depression
Differences in Gender
Women and men experience depression differently. Men may exhibit the signs of depression more in terms of fatigue, irritability or anger, loss of interest in once-pleasurable activities and sleep disturbances, while women may have feelings of sadness, worthlessness or excessive guilt.5 Men are more likely than women to turn to alcohol or drugs to cope with their depression. Women are 3 times more likely than men to attempt suicide while suffering from depression but men are 4 times more likely to complete it as they choose more lethal means.11
Women are at significantly greater risk than men to develop Major Depressive Episodes at some point during their lives, with the greatest differences found in studies conducted in the United States and Europe. The actual reported proportion of the adult population with major depressive disorder varies widely depending on which study is referenced. The lifetime risk for major depressive disorder in community samples has varied from 10% to 25% for women and from 5% to 12% for men. The point prevalence of major depressive disorder in adults in community samples has varied from 5% to 9% for women and from 2% to 3% for men. A recent National Comorbidity Survey Replication found the following lifetime prevalence rates of major depressive disorder: 13.2% for men and 22.5% for women.6 While the prevalence rates for Major Depressive Disorder appear to be unrelated to ethnicity, education, income, or marital status, studies seem to indicate that there are gender differences with most studies indicating that depressive episodes occur twice as frequently in women as in men.
Read more Depression in Women
Read more Depression in Men
Differences in Cultural Background/Ethnicity
Culture can influence the experience and communication of depression symptoms. Under-diagnosis or misdiagnosis can be reduced when clinicians are attentive to ethnic and cultural nuances that affect the presentation of depression symptoms in diverse populations, individuals and ethnic groups. For example, in some cultures, the depression symptoms may be experienced largely in somatic terms, rather than with sadness or guilt. Complaints of “nerves” and headaches (in Latino and Mediterranean cultures), of weakness, tiredness, or “imbalance” (in Chinese and Asian cultures), of problems of the “heart” (in Middle Eastern cultures), or of being “heartbroken” (among Hopi Native Americans) may describe the diversity of culturally expressed depressive experiences.11It is also imperative that neither a clinician nor an individual not dismiss a symptom just because it is viewed as the norm for that culture.
- National Institute of Health, Depression Handbook, see http://www.nimh.nih.gov/health/publications/depression/complete-index.shtml
- American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders, fourth edition: Text revision. Washington, D.C: Author.
- Klerman, G. L. (1986). The National Institute of Mental Health—Epidemiology Catchment Area (NIMH-ECA) program: Background, preliminary findings and implications. Social Psychiatry, 21, 159-166.
- Weissman, M. M., & Myers, J. K. (1978). Affective disorders in a US urban community: The use of Research Diagnostic Criteria in an epidemiological survey. Archives of General Psychiatry, 35, 1304-1311.
- Wexler, D. B. (2005). "Is he depressed or what”: What to do when ?the man you love is irritable, moody, and withdrawn. Oakland, CA: New Harbinger, Inc.
- Kessler, R. C., McGonagle, K. A., Swartz, M., Blazer, D. G.. & Nelson, C. B. (1993). Sex and depression in the National Comorbidity Survey I: Lifetime prevalence, chronicity, and recurrence. Journal of Affective Disorders, 29, 85-96.
- Bebbington, P. E., Dunn, G., Jenkins, R., Lewis, G., Brugha, T., Farrell, M., & Meltzer, H. (2003). The influence of age and sex on the prevalence of depressive conditions: Report from the National Survey of Psychiatric Morbidity. International Review of Psychiatry, 15(1-2), 74-83.
- Hankin, B. L., & Abramson, L. Y. (2001). Development of gender differences in depression: An elaborated cognitive vulnerability-transactional stress theory. Psychological Bulletin, 127(6), 773-796.
- Calvete, E., & Cardenoso, O. (2005). Gender differences in cognitive vulnerability to depression and behavior problems in adolescents. Journal of Abnormal Child Psychology, 33(2), 179-192.
- Cyranowski, J., Frank, E., Young, E., & Shear, K. (2000). Adolescent onset of the gender difference in lifetime rates of major depression. Archives of General Psychiatry, 57(1), 21-27. 13) Ingram, R. E., Scott, W., & Siegle, G. (1999). Depression: Social and cognitive aspects. In T. Millon, P. H.. Blaney, & R. D. Davis’s (Eds.), Oxford Textbook of Psychopathology. New York: Oxford University Press.
- American Foundation for Suicide Prevention (2010). Facts and Figures by Gender. Retrieved from: http://www.afsp.org/index.cfm?fuseaction=home.viewpage&page_id=04ECB949-C3D9-5FFA-DA9C65C381BAAEC0
- Steffens, DC. A multiplicity of approaches to characterize geriatric depression and its outcomes. Current Opinion in Psychiatry 2009 Nov; 22(6): 522-6.