Fig. 1 Number of US geriatric psychiatry programs and fellows with percentage of US population 65 years and older, 2001-2012.

Fig. 2 Population projections for individuals 65 years of age or older, United States, 2000-2060.

General Mental Health

The WHO estimates that mental health disorders are the most common cause of disabilities in people worldwide. Neuropsychiatric disorders caused about a third of all years lost due to disability (YLDs) in 2004. Furthermore, there is a greater burden of mental health problems in women, with mental disorders making up 3 of the top 10 leading causes of disease burden for women in low- to mid-income countries, and 4 of the top 10 for women in high-income countries.5

The World Mental Health Survey is a survey of mental health problems conducted in 17 countries from 2001 through 2003.6 Based on the results of this study, the United States has the highest prevalence of mental illness (26.4%) compared with global estimates. Other countries range from 4.3% (Shanghai, China) to 20.5% (Ukraine). Internationally, anxiety (2.4%–18.2%) and mood (0.8%–9.6%) disorders are the most important contributing factors, and most disorders are classified as mild to moderate severity.6

In the United States, the Centers for Disease Control and Prevention conducts annual health surveys that collect general information on mental health. The National Health Interview Survey collects information on selected mental health characteristics. In 2011, the overall age-adjusted percentage of individuals who reported experiencing the following symptoms all or some of the time, respectively, is as follows:

Individuals aged 65 to 74 years and 75 years and older reported similar trends, with those who reported feeling sadness some of the time (9.3% for 65–74 years, and 9.0% for 75 years and older) being higher than the national average.7

Depression

Depressive disorders are debilitating health problems that are the leading cause of disability worldwide.5,8 These disorders are characterized by loss of interest in activities, changes in weight and sleeping patterns, fatigue, and feelings of guilt and worthlessness.9 Depression can lead to impairments in one’s ability to function socially, decreased quality of life, and increased risk of health problems.10 Finally, it is one of the most common chronic diseases in the general population.10 In 2000, it was estimated that depression cost the United States $83.1 billion in economic costs, including $26.1 billion in direct health care costs and $51.5 billion in workplace costs based on absenteeism.11

Estimates vary regarding rates of depression and depressive symptoms in the United States by source. During 2005 to 2006, the National Health and Nutrition Examination Survey (NHANES) reported that greater than 5% of individuals in the United States experienced depression. These rates varied by age, gender, race/ethnicity, and socioeconomic status.12 Based on the 2006 and 2008 Behavioral Risk Factor Surveillance System, 9.1% of the US population met the criteria for depression.13 This survey also showed differences in rates of depression by age, gender, race/ethnicity, and socioeconomic status. In both surveys, depression increased with age, with those between the ages of about 40 and 64 years old having the highest prevalence of depression. Women were more likely to have symptoms of depression than men, and non-Hispanic white individuals were less likely to report depression than individuals of other racial or ethnic groups.12,13 Low income,12 low education, unemployed status, and having no health insurance were also related to higher rates of depression.13 Of individuals reporting symptoms of depression, 80% reported functional impairment. Less than half of these reported contacting a physician or mental health professional for their symptoms.12

Among the US population aged 65 years and older, 4.1% reported major depression, 5.1% reported other depression, and 9.1% reported any depression in 2006, according to NHANES.13 In 2010, it was estimated that between 1.2 and 1.8 million adults 65 years of age and older had a depressive disorder, or 3.0% to 4.5% of this age group. Rates of depressive disorders in community-dwelling elderly persons over the age of 65 vary by race/ethnicity, with the highest rates of depressive disorders being among the Hispanic/Latino populations. Older whites, African-Americans, and Asians report rates of depressive disorders about 3.6% to 4.0%, but older Hispanics report rates of 6.9%. Among individuals in this age group who are in nursing homes, the prevalence of depression is significantly higher (49.6%).14

According to NHANES data from 2005 through 2010, 61.72% of individuals aged 65 years and older reported having at least one symptom of depression in the 2-week period before the survey (Table 1). The most common symptoms reported in this age group include “feeling tired or having little energy,” “trouble sleeping or sleeping too much,” “little interest in doing things,” and “feeling down, depressed, or hopeless” (Table 2). Of those with at least one symptom of depression, 23.72% reported that their symptoms caused them some to extreme difficulty in their daily...