Geriatric Psychiatry

Late-life Depression

Depression in late life lowers life expectancy. Depression and cognitive impairment affect approximately 25% of the elderly. New research confirms that the risk for post-stroke depression increases especially in the “old-old” (i.e., those over 85 years of age). Depression in the elderly is not more common according to Epidemiological Catchment Area (ECA) data; however, making the diagnosis is more difficult. A higher rate of depression exists in older women as compared to older men; among those with a history of depression there is a 50% chance of a second episode (either a recurrence or a relapse). Use of medications for medical problems often generates adverse effects and complicates the diagnosis of depression; moreover, medical illness may mimic depression and depression may mimic medical illness. Depression (as occurs with stroke, fractured hip, arthritis, and cardiac illness) is common in disabled elderly. Depression is also associated with both acute and chronic medical illnesses and late-onset depression is closely associated with physical illness. Of note, undiagnosed medical illness can manifest as depression. Grief and loss may also contribute to depression. As many as 60% of depressed patients have co-morbid anxiety and 40% of anxious patients have co-morbid depression.

Neurological disorders also complicate the diagnosis of depression. The risk for depression in the post-stroke period is high, with 25% to 50% developing depression within 2 years of the event. Alzheimer's disease (AD) carries an increased risk of depression; approximately 20%–30% (either before or at the time of diagnosis) are diagnosed with depression. Delusions are also prominent in depression associated with dementia. Recent research confirms the association of depression with the increased risk of developing late-onset AD. Fifty percent of patients with Parkinson's disease develop depression or have a history of depression with anxiety, dysthymia, or frontal lobe dysfunction. Degeneration of the sub-cortical nuclei (especially the raphe nuclei) is related to the development of depression in Parkinson's disease.

Assessment of depression can be challenging. The Geriatric Depressions Scale ( Table 71-2 ) is a helpful tool in this regard, and often the information provided by the caregiver is crucial as elders may not be forthcoming with their symptoms. However the PHQ-9 used in the primary care office is simpler to complete and therefore more readily used. The criteria for diagnosing depression in the elderly are the same as they are in the general population.

Treatment of late-life depression is challenging in part because there is a decline in one's biological ability to metabolize drugs and to bind proteins (because of reduced receptor sensitivity), as well as an increased sensitivity to drug side effects. In an effort to reduce adverse consequences of medications, drugs with the fewest side effects should be started (and be used in small doses); in addition, monotherapy should be attempted ( Tables 71-3 and 71-4 ). In more refractory cases or with psychotic symptoms, electroconvulsive therapy (ECT) should be considered early in treatment and as an adjunct for one or more drugs. Individual psychotherapy or group therapy complements somatic treatments and often leads to a swift recovery. Interpersonal therapy and cognitive-behavioral therapy (CBT) are both suited to this population as they are more focused and interactive treatments.

Late-life Depression and Suicide

Depression with psychotic features is linked with a higher risk of suicide. The rate of suicide in those greater than 65 years is double that of the rate for the US population in general, and those with the highest suicide rates of any age group are those aged 65 years and older. In 2011, suicide ranked as the 10th leading cause of death among those aged 65; this group represented 12.5% of the population, but it accounted for 15.7% of all suicides. Suicide disproportionately affects the elderly; the suicide rate among those 65 to 69 years old was 13.1 per 100,000 (N.B.: all of the following rates are per 100,000 population), and the rates increased as age increased (i.e., it was 15.2 among those between 70 and 74, it was 17.6 among those between 75 and 79, it was 22.9 between those 80 and 84, and it was 21.0 between persons 85 or older). Firearms (71%), overdose (11%), and suffocation (11%) were the three most common methods of suicide used by persons aged 65 years or older. Firearms are the most common method of suicide by both males and females, accounting for 78% of men and 35% of women who committed suicide in that age group and cohort.

Risk factors for suicide among the elderly differ from those among the young. In addition to a higher prevalence of depression, older persons are more socially isolated and they more frequently use highly lethal methods. They also make fewer attempts per completed suicide, have a higher male-to-female ratio than other groups, have frequently visited a health care provider before their suicide, and have more physical illnesses. Approximately 20% of elderly (i.e., over 65 years) persons who commit suicide have visited a physician within 24 hours of their death, 41% visited within 1 week of their suicide, and 75% were seen by a physician within 1 month of their suicide. Of every 100,000 people aged 65 and older, 14.3 died by suicide in 2004. This figure is higher than the national average of 10.9 suicides per 100,000 people in the general population. Caucasian men aged 85 or older had an even higher rate, with 17.8 suicide deaths per 100,000. Suicide rates among the elderly are highest for those who are divorced or widowed. Among men aged 75 years and older, the rate for divorced men was 3.4 times that for married men, and for widowed men it was 2.6 times that for married men. In the same age group, the suicide rate for divorced women was 2.8 times that of married women, and for widowed women it was 1.9 times the rate among married women. Several factors (including growth in the size of that population; health status; availability of, and access to, services; and attitudes about aging and suicide) relative to those over 65 years will play a role in future suicide rates among the elderly.

Suicide occurs early (often during the first 6 months) in the illness, but it can occur at any time, often in combination with other mental disorders. More than 90% of older people who commit suicide have the following risk factors: depression or other mental disorders; a substance abuse disorder or a family history of such; stressful life events, in combination with other risk factors, such as depression; a prior suicide attempt or family history of an attempt; family violence (including physical or sexual abuse); firearms in the home (the method used in more than half of suicides); incarceration; or exposure to the suicidal behavior of others, such as family members, peers, or media figures. The rate of completed suicide is greater in this population than in any other age group; older adults account for 25% of all suicides. Older white males make up the highest-risk group, and rates are increasing. Isolation increases the risk for suicide, and alcoholism or substance abuse is a contributing factor to successful suicides in all populations, including older adults. Aggressive treatment with antidepressants is indicated for these individuals, and inpatient treatment is the safest venue for care.

Most of the antidepressants are equally effective for depression; however, drugs with anticholinergic effects and undue sedation should be avoided to reduce complications (such as falls, confusion, and poor compliance). However, matching the symptoms with the side effects is useful for a patient with significant weight loss and insomnia; a sedating medication that increases appetite may be beneficial. ECT early in the course of major depressive disorder (MDD) should be considered strongly as appropriate care of this high-risk population.

Alcoholism

Alcoholism, often overlooked in many patients, may go unnoticed in older adults despite a lifelong pattern of daily drinking; even if the elderly drink only small amounts, they may experience a significant and life-threatening withdrawal. Co-morbid illness (both psychiatric and medical) confounds accurate diagnosis of both the alcoholism and the medical or surgical diagnosis. Symptoms of problem-drinking include insomnia, memory loss, confusion, anxiety, and depression, as well as somatic complaints that may mimic medical illness, further delaying accurate diagnosis. Older adults who drink alcohol are at greater risk due to the fact that often they take more prescribed medications that can interact adversely with alcohol.

The prevalence of alcoholism in the ECA study was 1.5% to 3.7%. Although cross-sectional studies suggested that the percentage of alcoholism declines after age 60, longitudinal studies propose a stable pattern of lifelong alcohol abuse. Women drink less than men at all ages, but older widowed women are at risk for increasing their intake. Studies note that the prevalence of alcohol problems in women is on the rise. Older adults with alcohol dependence also have a high prevalence of co-morbid nicotine dependence. Alcohol dependence can lead to liver damage, cancer, immune system disorders, and brain damage.

Depression is more common in those with alcoholism, as is grief, anxiety, psychosis, and dementia. Suicide risk is greater in elderly alcoholics; therefore, obtaining a comprehensive history from family, friends, and caretakers is essential. Hospitalization is typically required for detoxification of the older patient. Newer medications (such as naltrexone and acamprosate) and the familiar disulfiram (Antabuse) can be beneficial, but disulfiram may generate problematic side effects in older adults.