Investigators discovered the genetic variation can cause a six-fold greater risk for children to develop metabolic syndrome. Metabolic syndrome is a combination of symptoms that increase the risk for cardiovascular disease.
The study showed susceptible children displayed an increased risk to develop high blood pressure and elevated fasting blood sugar levels (a precursor to diabetes).
The research is published in the medical research journal Translational Psychiatry.
“This is the first report of an underlying biological factor predisposing children to complications associated with second-generation antipsychotic medication use,” said Dr. Dina Panagiotopoulos, study co-author.
“It’s concerning because these children take medications to treat a chronic disease – mental illness – and then develop risk factors for a second chronic disease,” said co-author Dr. Angela Devlin.
Second-generation antipsychotics such as quetiapine (Seroquel) and risperidone (Risperdal) are prescribed to approximately 5,500 children and youth in British Columbia for psychotic disorders like schizophrenia, mood and anxiety disorders, attention deficit hyperactivity disorder, autism spectrum disorders, adjustment disorders and substance abuse.
Researchers assessed 209 children who were inpatients between April 2008 and June 2011 at the Child & Adolescent Psychiatry Department at BC Children’s Hospital.
Their average age was 13 years, and 105 of the children were treated with second-generation anti-psychotics while 112 did not use these drugs.
DNA analysis showed that eight per cent of children from both groups had a genetic variation called C677T on the MTHFR gene. Children with the MTHFR C677T variant who used these medications were six times more likely to have metabolic syndrome.
The researchers targeted the MTHFR C677T variant because it is known to be associated with metabolic syndrome in adults who have schizophrenia, and with cardiovascular disease in adults who don’t have psychiatric illness.
Devlin and Panagiotopoulos said their discovery is an important step in preventing and managing metabolic complications associated with second-generation antipsychotic medications.
Researchers believe the knowledge is critically important to reduce these risks in childhood because adults with mental illness have a 19 per cent increased mortality rate that is largely due to cardiovascular disease risk.
Future investigations will incorporate a study of vitamin B status among affected children as the MTHFR gene is involved in metabolizing the B-vitamin folate.
“We now plan to assess B vitamin status and dietary intake in children who take these medications to gain a better understanding of this association,” said Panagiotopoulos.