The diminution of depression is much slower in people who have suffered physical abuse or experienced parental addictions in their childhood than those who haven't gone through such hardships, finds a new study.
University of Toronto investigators examined a range of factors associated with remission in a sample of 1,128 depressed Canadian adults, drawn from the National Population Health Survey.
Depressed individuals were followed every other year until remission occurred, for up to 12 years.
"Our findings indicated that most people bounce back. In fact, three-quarters of individuals were no longer depressed after two years," co-author Emeriti Tahany M. Gadalla reported. However, not everyone recovered at the same rate.
Lead author Esme Fuller-Thomson, Sandra Rotman Endowed Chair in the University's Factor-Inwentash Faculty of Social Work said that early adversities have far-reaching consequences and the average time to recovery from depression was 9 months longer for adults who had been physically abused in their childhood and about 5 months longer for those whose parents had addiction problems.
Co-author Marla Battiston said that numerous studies have shown that childhood abuse and parental addictions make individuals more vulnerable to depression, but their research highlights that these factors also slow the recovery time among those who become depressed.
Although this study could not determine why childhood adversities are associated with poor depression outcomes, the researchers speculate that negative experiences may interrupt the normal development of the hypothalamic-pituitary-adrenal axis, which affects stress regulation.
The study is published in the journal Social Psychiatry and Psychiatric Epidemiology.