Mood disorders, also called affective disorders, represent a spectrum of mental health illnesses in which prolonged periods of sadness (depression) are on one end and signs of excessive elation (mania) are on the other end. Manifestations of both ends of the spectrum at different times in an individual is termed bipolar disorder.
Major depression manifests as significant depressive episodes without any manic symptoms, often referred to as unipolar depression; it is far more common than mania alone. The lifetime risk for a major depressive disorder is 9% for men and approximately 17% for women. In developed countries, the prevalence of this disorder is around 18%, whereas in underdeveloped nations, it is around 9%. Major depression may occur at any age, but it most commonly affects middle-aged persons. Elderly individuals who live in health care facilities and individuals affected with a wide range of acute and chronic disease also appear to be at higher risk.
Major depression is a disabling condition that causes impairment of basic physical functions, as manifested by sleep disturbances, changes in appetite with associated weight loss or gain, diminished libido, and an inability to experience pleasure (anhedonia). Affective changes include pervasive and persistent low mood, slowed thought processes, low self-esteem, and loss of interest or pleasure in normal activities. Social withdrawal and psychomotor retardation are observed, although agitation can also occur. Patients commonly report somatic symptoms such as fatigue and headache, as well as other nonspecific symptoms. The risk of suicide in the depressed patient is over 25 times that of the general population; factors associated with suicide risk include the degree or longevity of the disorder, male sex, the family history of psychiatric disorder, and the presence of comorbidity. Patients with dysthymic disorder have chronic, less severe depressive symptoms that do not meet the criteria for major depression.
Mania is a period of abnormally and persistently elevated or irritable mood that is sufficiently severe to impair social or occupational functioning. Typical symptoms include euphoria or irritability, grandiosity, decreased need for sleep, increased speed of thought and speech (flight of ideas), and increased goal-directed activity. Formerly called manic depression, bipolar disorder is found in approximately 3% of people. It manifests in 2 forms. Bipolar I disorder describes any illness in which mania is present, whether or not depression occurs. Bipolar II disorder refers to patients with major depressive episodes and at least one mild manic episode (hypomania). Cyclothymic disorder describes cyclical episodes of mania and mild depression.
For the nonpsychiatric clinician, depression creates several problems. In some patients, mood change may not be apparent, and the illness may manifest in somatic symptoms, leading to time-consuming, expensive workups. Conversely, in patients known to be depressed, an organic disease may be overlooked as psychosomatic. Recommendations for psychotherapeutic intervention may be met with resistance, anger, or denial, disrupting the patient–physician relationship. Patients may have difficulty adhering to diagnostic and treatment regimens for medical disorders and surgical procedures. A screening study of older patients attending an ophthalmology clinic showed that 1 in 5 patients suffered from depression. Visual impairment almost doubles the risk of depression. In a recent study, the prevalence of depression in patients with macular degeneration was as high as 39%. The American Academy of Ophthalmology’s Preferred Practice Pattern Guidelines recommend screening all macular degeneration patients and providing appropriate referrals for those suspected of having depression.
American Academy of Ophthalmology Retina/Vitreous PPP Panel, Hoskins Center for Quality Eye Care. Preferred Practice Pattern® Guidelines. Age-Related Macular Degeneration. San Francisco: American Academy of Ophthalmology; 2015. Available at www.aao.org/ppp.
Cimarolli V, Casten RJ, Rovner BW, Heyl V, Sörensen S, Horowitz A. Anxiety and depression in patients with advanced macular degeneration: current perspectives. Clin Ophthalmol. 2015;10:55–63.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.