Pediatric Depression: Factors to Consider in Treatment

Recent reports suggest more children are experiencing depression. In a study published in the Journal of Abnormal Psychology, rates of depression among adolescents aged 14 to 17 increased by more than 60 percent between 2009 and 2017.

“There is an overwhelming amount of data from many different sources, and it all points in the same direction: more mental health issues among American young people,” Jean Twenge, Ph.D., one of the study’s authors and a professor of psychology at San Diego State University, told Time Magazine. “There should no longer be any doubt. There is a mental health crisis among American teens and young adults.”

As further evidence, the number of U.S. children and teenagers visiting emergency rooms as a result of suicidal thoughts and attempts has doubled from 2007 to 2015, according to a CNN report.

These numbers do not surprise Dr. Gene Beresin, executive director of The Clay Center for Young Healthy Minds at Massachusetts General Hospital and professor of psychiatry at Harvard Medical School. Dr. Beresin was quoted in the report saying: “We know that suicide and depression have been rising significantly. Kids are feeling more pressure to achieve, more pressure in school, and are more worried about making a living than in previous years.”

Now is the time to focus on childhood depression and other mental health illnesses. May 6 marks National Children’s Mental Health Awareness Day. According to the Substance Abuse and Mental Health Services Administration, this day shines “a national spotlight on the importance of caring for every child’s mental health and reinforces that positive mental health is essential to a child’s healthy development.”

Caring for a child’s mental health is a selfless task and a huge responsibility. Using pharmacogenomics in the pediatric population can make a difference and reduce trial and error in the prescribing process.

Prescribing Antidepressants in the Pediatric Population

Doctors often rely on several different factors in determining which medications may work for their patients, including:

1. Patient experience
2. Adverse effects
3. Adherence
4. Family history
5. Cost
6. Illness

However, two of these factors can be compromised when working with children.

First, pediatric patients may have difficulty articulating medication response; specifically, the efficacy of the medication and any side effects they may be experiencing. As a result, the “patient experience” portion of medication selection cannot be used if the patient cannot articulate his or her response.

Likewise, “adverse effects” can be compromised in the decision-making process. Prescribing medication for pediatric patients presents the potential for toxic or sub-therapeutic outcomes. This is because children experience changes in their metabolic activity, especially at a young age.

Moreover, there is a scarcity of psychiatric medication trials with young patient subjects. As a result, available data to demonstrate medication efficacy or potential for side effects for children is lacking. Parents may then express concerns about the lack of evidence-based research with a particular therapy, and not want healthcare providers to prescribe it to their child.

Pharmacogenomics Can Help Provide Insight

More doctors are starting to use pharmacogenomics in their practices to help guide medication decisions and overcome these challenges. Pharmacogenomics uses information about a person’s genetic makeup, or genome, to identify the drugs or drug doses that are likely to be genetically optimal for that patient.

The GeneSight Psychotropic test is one example of a pharmacogenomic test designed for use in mental health. Of importance to the pediatric population is pharmacokinetic information outlined in the GeneSight test results. These show genetic variation that may result in certain medications being broken down faster or slower than normal.

Pharmacokinetic genes can affect medication blood levels. There are four general types of metabolizers:

• An ultra rapid metabolizer breaks down medications rapidly and may not get enough of the medication at normal doses
• An extensive (normal) metabolizer breaks down medications normally and has normal amounts of medications at normal doses
• An intermediate metabolizer breaks down medications slowly and may have too much medications at normal doses
• A poor metabolizer breaks down medications very slowly and may experience side effects at normal doses.

Understanding How Physiological Changes Can Impact Pediatric Patients

Pediatric physiology can be very different from adult physiology. Enzymes responsible for breaking down medications will change based on a child’s age, but they will reach adult levels or above fairly early in life. Those enzymes that are not stabilized in childhood actually exceed adult levels before coming back down. For example, the hepatic enzyme CYP3A4 exceeds adult levels in childhood and then falls to normal adult levels at the end of puberty. The enzymes CYP2C9 and CYP2C19 exceed adult value at 3 to 4 years of age, but then decline to normal adult levels at the end of puberty. From a safety perspective, this is a good thing since it would likely result in the dosing being too low in children instead of too high.

Childhood and teenage depression can be challenging to treat, especially as more patients are presenting with these mental health issues. As your patients’ parents, guardians and caregivers share concerns about giving their child medication, pharmacogenomics can help alleviate some of the guess work when making decisions about dosage and which medications are genetically optimal for your pediatric patients.