Adversity in childhood plays an important role in the development and course of depression and a number of studies have shown links between depression and people's memories of parental indifference, overcontrol and physical and sexual abuse. A team of American researchers led by Daniel N. Klein from Stony Brook University in New York looked into the links between childhood adversity, people's depression symptoms and how well they responded to treatment in a sample of 808 people with chronic major depression. They found that childhood adversity was associated with a longer-lasting illness, an earlier onset of depression, more incidents of depression, more severe symptoms, functional impairment, suicidal thoughts, anxiety, dysfunctional attitudes and a tendency to be self-critical. A history of maternal overcontrol, paternal abuse, paternal indifference and sexual abuse each predicted a lower probability of remission. In a 12-week trial of antidepressant treatment 44% of people without a history of childhood abuse got better compared to 32% of people with a history of childhood adversity.
Klein, Daniel N. ... [et al] - Early adversity in chronic depression: clinical correlates and response to pharmacotherapy Depression and Anxiety August 2009, 26(8), 701-710
In another study on the same theme researchers from the universities of Otago and Canterbury in New Zealand studied 195 people taking part in a clinical trial of the antidepressants fluoxetine and nortriptyline. They found that participants who reported low paternal care were less likely to finish the six-week trial of the drugs. Participants who said that they had had overprotective mothers had a worse response to treatment after six weeks and were less likely to show two-months of sustained recovery after the end of the trial. However, sexual, physical or psychological abuse did not seem to affect people's response to the treatment.
Johnstone, Jeannette M. ... [et al] - Childhood neglect and abuse as predictors of antidepressant response in adult depression Depression and Anxiety August 2009, 26(8), 711-717