Depression

Feeling blue or sad is an appropriate response to a difficult situation. Clinical depression occurs if the reaction is more severe or prolonged than expected. Major depression is a mood disorder characterized by at least 2 weeks of depressed mood, a loss of interest or pleasure in usual activities, and a feeling of hopelessness associated with other findings such as sleep disturbances or loss of energy. Major depression is a chronic debilitating disease with a lifetime prevalence of 7% to 12% in men and 20% to 25% in women. It often accompanies chronic medical illnesses and substance abuse.
  A less severe form of depression is dysthymia. It lasts at least 2 years and is described by some as a depressive type of personality. Although symptoms are not as severe as seen in major depression, they persist too long to be considered an adjustment reaction. Most patients with depression seek help from a family physician rather than a psychiatrist, making it important that the family physician feels comfortable managing this illness. Despite the prevalence of depression, the diagnosis is missed in up to 50% of family practice patients; even when diagnosed, it is often undertreated indications for screening for depression in adults, children, and adolescents.

PATHOGENESIS OF DEPRESSION AND SIGNS AND SYPTOMS

Most theories explaining depression emphasize a biologic model. Depression is thought to be related to dysregulation of the brain's neurotransmitters. Although an imbalance in neurotransmitters provides an explanation for symptoms, it is still unclear why the imbalance develops. Research suggests that genetic factors play a role and that some individuals appear to be predisposed to developing depression. in response to stressors. Potential stressors include medical illness, stressful life events, unresolved losses, poor support systems, and life changes affecting lifestyle, such as divorce or financial loss. The process by which environmental factors interact with biologic factors to cause depression is still poorly understood.

CLINICAL MANIFESTATIONS OF DEPRESSION

HISTORY

Depression can cause a wide range of psychological and somatic complaints. The average age of onset of depression is from 20 to 40 years of age, although it can first present at any age. Identifiable stressors often play a role in the first episode of depression but may play a limited role or have no role in subsequent episodes. A concern expressed by a family member or friend about crying spells or depressed mood should prompt the physician to ask questions about depression. The patient's past medical history should be reviewed, since illnesses such as stroke, epilepsy, cardiovascular disease, chronic fatigue syndrome, dementia, diabetes, cancer, rheumatoid arthritis, and HIV are frequently associated with depression. A family history of depression significantly increases the risk for depression. A careful review of medications is indicated, since some medications can precipitate depression.
Many patients with depression first seek treatment for physical symptoms, and depression should be considered in patients with somatic complaints such as headache, backache, fatigue, chronic abdominal or pelvic pain, sleep disorders, sexual dysfunction, and a generalized positive review of systems. An old adage states that if there are more than four complaints, consider depression. Eliciting the patient's social history, particularly regarding alcohol and other substance use, is important. Some individuals presenting with depression have manic-depressive illness, so it is important to ask about episodes of mania. The severity of depression may be assessed by asking about suicidal thoughts and psychotic symptoms. Risk factors for suicide include social isolation (e.g., divorced, widowed, living alone), substance use, elderly male, persons with terminal or chronic illnesses, and those who have developed a specific plan. Although women attempt suicide more often, men succeed more often.

PHYSICAL EXAMINATION FOR DEPRESSION

A physical examination helps screen for medical disorders. Assessing mental status and appearance, mood, affect, speech, thought content, perceptual disturbances, and cognition is important. Psychomotor retardation, poor eye contact, tearfulness, poor grooming, somber affect, and impaired memory are characteristics of depression.

DIFFERENTIAL DIAGNOSIS

Several conditions besides depression can cause a depressed mood. An adjustment disorder with a depressed mood occurs when an identifiable stressor cuses more symptoms than expected but does not last more than 6 months. Grief reactions may also resent with symptoms mimicking depression; however, symptoms begin to improve after a few months. An anxiety disorder can mimic depression but is not usually accompanied by depressive symptoms such as loss of appetite and fatigue. Anxiety disorder is dominated by feelings of apprehension, whereas depression is dominated by sadness and hopelessness. A bipolar disorder or substance abuse may also present with symptoms similar to those of depression. In addition to psychological diseases, certain medications and medical illnesses such as chronic infections (e.g., HIV, TB), endocrine disorders (e.g., hypothyroidism, hyperthyroidism, Cushing disease, and Addison disease), connective tissue diseases, neurologic disorders, and cancers are associated with depression.

DIAGNOSTIC EVALUATION FOR DEPRESSION

The clinical interview is the most effective means of diagnosing depression. Laboratory testing such as a CBC, basic chemistries, UA, Venereal Disease Research Laboratories (VDRL) testing, HIV testing, and a vitamin B12 level may be helpful in ruling out a medical disorder. A baseline ECG should be performed in patients with a history of cardiac disease or those who are over age 40 if tricyclic antidepressants are going to be prescribed. Neuroimaging and an electroencephalogram (EEG) should be considered for patients with new onset psychotic depression.

TREATMENT FPR DEPRESSION

Common treatments include supportive counseling and pharmacotherapy. Examples of supportive counseling include providing education, empathizing with the patient, challenging a patient's exaggerated negative or self-critical thoughts, and encouraging him or her to be more active and schedule enjoyable activities. Sometimes encouraging patients to break their problems down into smaller components is helpful. Often a willingness to explore issues is therapeutic, although the physician should not he expected to address and solve all problems. Patients with family or marital issues may benefit from therapy. Patients with persistent symptoms or major depression should be treated pharmacologically.
The different classes of antidepressant medications are equally effective. The choice of medication depends on the patient's symptoms, current medications, and side-effect profile. If the patient has insomnia, a more sedating medication such as a tricyclicantidepressant, trazodone, or mirtazapine is a good choice. If somnolence is a problem, a more energizing antidepressant such as a SSRI or bupropion might be chosen.
Although SSRIs are typically energizing, about 15% of patients experience sedation as a side effect. If anxiety or agitation is a complaint, SSR.Is should be avoided as a first choice. Sedative antidepressants should be given in this situation. Although tricyclic antidepressants (TCAs) have been available for years, they have many unpleasant side effects. Their anticholinergic properties can precipitate an attack of acute angle glaucoma or bladder outlet obstruction. They can also cause constipation, dry mouth, orthostatic hypotension, tachycardia, cardiac arrhythmias, tremor, and weight gain. SSRIs appear to be safe in patients with cardiac disease and cause less orthostatic hypotension in elderly patients. Common side effects include GI disturbances, headache, agitation, insomnia, sexual dysfunction, tremor, and somnolence. Trazodone has minimal anticholinergic side effects but is very sedating and on rare occasion causes priapism in males. Venlafaxine combines SSRI properties with noradrenergic effects. It is often used for refractory depression, but its side effects limit its use as a first-line agent. MAOIs are effective but less commonly used because of their potential for drug and food interactions.
About 60% of patients will respond to a given antidepressant and 80% will respond to a second alternative or added antidepressant medication. Patients should be assessed for therapeutic response and adverse effects of their medication within the first 2 weeks; however, therapy should be continued for 6 to 8 weeks before evaluating for effectiveness or changing the medication. The greatest risk of increased suicidal thoughts and behaviors is in the first to second month of treatment and close follow-up is recommended to identify these events early. For severe cases of major depression, some patients may require multiple medications to achieve a therapeutic response to treatment.
For a first episode of depression, antidepressants should be continued for 4 to 9 months after symptoms improve. Following a major depressive episode, about 50% of the patients relapse; the highest risk for recurrence is within the first few months of tapering an antidepressant. Patients suffering relapses should promptly be restarted on medications. The risk of relapse increases with each progressive episode and patients who relapse should he considered for long-term therapy. Patients who fail to respond to therapy, abuse substances, are suicidal, have accompanying psychosis, or show symptoms of mania should be referred to a psychiatrist.