People who may have had depression include English author Mary Shelley, American-British writer Henry James, and American president Abraham Lincoln. Some well-known contemporary people with possible depression include Canadian songwriter Leonard Cohen and American playwright and novelist Tennessee Williams. Some pioneering psychologists, such as Americans William James and John B. Watson, dealt with their own depression. There has been a continuing discussion of whether neurological disorders and mood disorders may be linked to creativity, a discussion that goes back to Aristotelian times. British literature gives many examples of reflections on depression. English philosopher John Stuart Mill experienced a several-months-long period of what he called "a dull state of nerves", when one is "unsusceptible to enjoyment or pleasurable excitement; one of those moods when what is pleasure at other times, becomes insipid or indifferent". He quoted English poet Samuel Taylor Coleridges "Dejection" as a perfect description of his case: "A grief without a pang, void, dark and drear, / A drowsy, stifled, unimpassioned grief, / Which finds no natural outlet or relief / In word, or sigh, or tear." English writer Samuel Johnson used the term "the black dog" in the 1780s to describe his own depression, and it was subsequently popularized by British Prime Minister Sir Winston Churchill, who also had the disorder. Johann Wolfgang von Goethe in his Faust, Part I, published in 1808, has Mephistopheles assume the form of a black dog, specifically a poodle. Social stigma of major depression is widespread, and contact with mental health services reduces this only slightly.
The relative increase in occurrence is related to pubertal development rather than chronological age, reaches adult ratios between the ages of 15 and 18, and appears associated with psychosocial more than hormonal factors. In 2019, major depressive disorder was identified (using either the DSM-IV-TR or ICD-10) in the Global Burden of Disease Study as the fifth most common cause of years lived with disability and the 18th most common for disability-adjusted life years.People are most likely to develop their first depressive episode between the ages of 30 and 40, and there is a second, smaller peak of incidence between ages 50 and 60. The risk of major depression is increased with neurological conditions such as stroke, Parkinsons disease, or multiple sclerosis, and during the first year after childbirth. It is also more common after cardiovascular illnesses, and is related more to those with a poor cardiac disease outcome than to a better one. Depressive disorders are more common in urban populations than in rural ones and the prevalence is increased in groups with poorer socioeconomic factors, e.g., homelessness. Depression is common among those over 65 years of age and increases in frequency beyond this age. The risk of depression increases in relation to the frailty of the individual. Depression is one of the most important factors which negatively impact quality of life in adults, as well as the elderly.