Neighborhood-level armed violence may increase children’s risk for MDD

Neighborhood-level armed violence appeared associated with increased risk for major depressive disorder among children, according to study results published in JAMA Network Open.

“The positive associations of adverse childhood experiences with depression coupled with the known deleterious effects of chronic stress on the developing brain lead us to hypothesize that indirect neighborhood-level violence might have particularly harmful effects for children,” Corina Benjet, PhD, of the National Institute of Psychiatry Ramón de la Fuente Muñiz in Mexico, and colleagues wrote. “Prior studies on children in war zones have generally focused on direct exposure, child soldiers or mediators or moderators of the effects of war on children.”

According to the researchers, neighborhood-level violence and depression has primarily been studied in middle- and high-income countries. Investigation of local community context across countries is necessary because of the heterogeneity of MDD and violence exposures worldwide, they noted.

In the current study, Benjet and colleagues sought to evaluate differences in associations between neighborhood-level violence and subsequent depression onset, independently of individual exposure and other key characteristics, among individuals aged younger than 11 years vs. older than 11 years. They analyzed data of 10,623 participants from 151 neighborhoods in Western Chitwan, Nepal, a low-income country that had medium-intensity armed conflict between 2000 and 2006. They included data collected during the armed conflict and linked it to lifetime histories of MDD, which were collected between 2016 and 2018, and eligible residents were those aged 15 to 59 years at MDD assessment.

Georeferenced number of physical beatings related to armed conflict within 1 km of a residential neighborhood served as the exposure. MDD as defined by DSM-4 criteria, during or after the conflict, stratified by age cohorts and assessed by the Nepal-specific World Mental Health-Composite International Diagnostic Instrument 3.0 with a life history calendar, served as the main outcome.

Participants contributed 171,899 person-years of exposure to the risk for MDD, and two or more beatings occurred within 1 km of 15 neighborhoods. Results of discrete-time survival models demonstrated an increased risk for developing MDD among children, but older individuals, who lived in neighborhoods with two or more beatings vs. those who lived in a community with no beatings (OR = 1.82; 95% CI, 1.17-2.84). The researchers observed a significant interaction between age group and neighborhood beatings (OR = 1.85; 95% CI, 1.27-2.7). Results of a confirmatory, multivariable, multilevel matching analysis showed a neighborhood association for children but not older individuals. Children who lived in neighborhoods with two or more beatings nearby had a mean incidence of MDD of 12.69% vs. 5.08% among the matched unexposed sample.

“Although we can never randomly assign violence to communities, this large multilevel prospective panel provides evidence suggesting that the youngest members of a community are the most at risk, with mental health consequences such as MDD that last long after the neighborhood trauma,” Benjet and colleagues wrote. “Rarely do any populations have enough resources to treat all exposed to violence. This evidence means that population-level interventions prioritizing those who were youngest at the time of the conflict may have the greatest benefits for population mental health.”