A new study has found that when parents are diagnosed with depression, it can have a significant negative impact on their children's performance at school.
Researchers at Drexel University led a team including faculty from the Karolinska Institutet in Stockholm, Sweden, and the University of Bristol in England in a cohort study of more than a million children born from 1984 until 1994 in Sweden. Using computerized data registers, the scientists linked parents' depression diagnoses with their children's final grades at age 16, when compulsory schooling ends in Sweden.
The research indicated that children whose mothers had been diagnosed with depression are likely to achieve grades that are 4.5 percentage points lower than peers whose mothers had not been diagnosed with depression. For children whose fathers were diagnosed with depression, the difference is a negative four percentage points.
Put into other terms, when compared with a student who achieved a 90 percent, a student whose mother or father had been diagnosed with depression would be more likely to achieve a score in the 85-86 percent range.
The magnitude of this effect was similar to the difference in school performance between children in low versus high-income families, but was smaller than the difference for low versus high maternal education (low family income: -3.6 percentage points; low maternal education -16.2 percentage points).
How well a student does in school has a large bearing on future job and income opportunities, which has heavy public health implications, explained Félice Lê-Scherban, PhD, assistant professor in the Dornsife School of Public Health. On average in the United States, she said, an adult without a high school degree earns half as much as one of their peers with a college degree and also has a life expectancy that is about 10 years lower.
"Anything that creates an uneven playing field for children in terms of their education can potentially have strong implications for health inequities down the road," Lê-Scherban said.
Some differences along gender lines were observed in the study. Although results were largely similar for maternal and paternal depression, analysis found that episodes of depression in mothers when their children were 11-16 years old appeared to have a larger effect on girls than boys. Girls scored 5.1 percentage points lower than their peers on final grades at 16 years old when that factor was taken into account. Boys, meanwhile, only scored 3.4 percentage points lower.
Brian Lee, PhD, associate professor in the Dornsife School of Public Health, said there were gender differences in the study's numbers, but didn't want to lose focus of the problem parental depression presents as a whole.
"Our study -- as well as many others -- supports that both maternal and paternal depression may independently and negatively influence child development," Lee said. "There are many notable sex differences in depression, but, rather than comparing maternal versus paternal depression, we should recognize that parental depression can have adverse consequences not just for the parents but also for their children."
Depression diagnoses in a parent at any time during the child's first 16 years were determined to have some effect on the child's school performance. Even diagnoses of depression that came before the child's birth were linked to poorer school performance. The study posited that it could be attributed to parents and children sharing the same genes and the possibility of passing on a disposition for depression.
The study, "Associations of Parental Depression With Child School Performance at Age 16 Years in Sweden," whose lead author was Drexel alumna Hanyang Shen, was published in JAMA Psychiatry.