Severe chronic depression more likely in child sex abuse victims

Chronic major depressive disorder, with episodes that last more than 24 months, affects almost half of patients seeking treatment for depression and carries with it significant problems in terms of disability, suffering and the cost of healthcare.

A piece of research carried out by Mauro García-Toro, a scientist from the University of the Balearic Islands (UIB), during a stay at Columbia University in New York, along with researchers from both institutions, reveals the main risk factors for this disease.

Published in the Journal of Affective Disorders, the study analyses several variables related to the physical and mental health of over 35,000 residents of the USA who are representative of the country's population.

After three years, the researchers got back in contact with the same people to observe how these variables had evolved and they focused on identifying the characteristics that increased the risk of severe chronic depression persisting once it has started.

As García-Toro explains to SINC: "Identifying risk factors for the persistence and remission of severe depression is important in order to progress in our understanding of the causes and development of the most effective preventative treatments and therapies."

The experts concluded that the highest risk variables for this illness were early onset of depression, delayed treatment, whether it is linked to other physical or mental health problems, and sexual abuse in childhood.

"The longer depression persists, the more likely the subjects interviewed are to recount having undergone sexual abuse, which no doubt means that they have been exposed to severe stress on many occasions in early life," notes García-Toro.

In fact, the researcher affirms that, "In addition to the usual psychological trauma, it has been demonstrated that this stress modifies the neurochemistry and structure of the brain, making it more vulnerable to depression."

Another consequence of abuse

The results reveal that 10% of all the people interviewed said that they had undergone sexual abuse as children, but of those who suffered severe depression for more than five years, this proportion approached 40%.

"These data are for men and women," the researcher points out. Thus, "as we know that sexual abuse is much more common in girls, it is highly likely that in the adult female population more than half of those with severe depression for more than five years suffered sexual abuse as children."

According to the authors, it is important to bring this situation to the fore in order to discover such examples -- as not all patients recount these events spontaneously -- and thus be able to intervene to improve treatment for those suffering from chronic depression.