According to the National Council on Aging, approximately one in four older adults in America have a mental health disorder. The most common mental health conditions include anxiety, severe cognitive impairment, and mood disorders such as depression. Depression is the most prevalent mental health problem among older adults.
Mental health is essential to overall well-being and it must be recognized and treated in all Americans, including older adults, with the same urgency as physical health.
http://www.thenationalcouncil.org/topics/older-adults-behavioral-health/
http://www.who.int/mediacentre/factsheets/fs381/en/