April 29, 2019

Associations Between Sickle Cell Disease and Mental Executive Functioning

People living with sickle cell disease (SCD) can experience changes in the ways that their brains process information. These changes can be seen and measured, even in early childhood. On June 14, 2018, Dr. Carlton Dampier of Emory University & Dr. Allison King of Washington University in St. Louis presented on the topic along with the FSCDR Symposium chair, Dr. Lanetta Brontè. In short, the effects noted by these experts could have a significant impact on school performance, finding and keeping a job, and interpersonal relationships. On a hopeful note, each panelist also covered straightforward actions that families and patients themselves can take to prevent or compensate for these effects.

WHAT IS EXECUTIVE MENTAL FUNCTIONING?

This term refers to the set of mental skills required to manage ones’ self and available resources to achieve a chosen goal. Typically, researchers in the field of neurocognition (a technical term that refers to the way we think of or feel about ourselves, our surroundings, and information) divide executive functioning (also called EF) into three categories¹. The first is working memory – how well you can retain, recall, and use new information. The next facet of executive function is mental flexibility, or the ability to shift from one task or situation to another. It can also describe a person’s ability maintain focus despite distractions. The third part of executive functioning is self-control. Sometimes, a child with an executive functioning deficiency can appear to have attention deficit hyperactivity disorder (ADHD).

The frontal lobe, or front one-third of the brain is devoted to these skills, but we are not born with a set amount of talent in these areas. People of all ages can learn and improve these skills or learn ways to compensate for deficiencies in one or more of the executive functions. The most influential factor in the initial development of EF is parental engagement in the newborn and early childhood period. Even older children and adults can benefit from resources and training in executive mental skills. Much like willpower, executive functioning can be intentionally built up with practice at any age.

Researchers can use testing to measure neurocognitive development in children as young as three months old². Evaluation of an individual’s executive function involves answering questions and working on tasks in front of a doctor or other health specialist. In addition, executive functioning correlates (progresses at a similar rate) with physical and electrical signaling changes in the brain. Doctors measure these changes by using medical imaging technology. Physical changes involving altered blood flow in the brain can be measured with magnetic resonance imaging (MRI). Changes in the way the brain uses electrical impulses to transmit signals between neurons (brain cells) can be tracked with functional neuroimaging (measures neuron activation while your brain is challenged with a task). EF can also change with age or in situations where a person is under stress or sleep deprived. Dr. Dampier reported the following risk factors that may contribute to EF decline in people living with sickle cell disease:

Inadequate sleep
Distractions caused by chronic or acute pain
Regular use of certain pain medications, including narcotics
Anxiety or depression
Physical and mental fatigue due to anemia
Strokes, Silent infarcts in the brain (small areas of damaged brain tissue that do not initially cause obvious stroke-like symptoms), or other physical changes in the brain related to sickle cell disease
Organ damage, like reduced kidney function, can influence how well your brain functions. Oxygen exchange occurs in the lungs, and without adequate oxygen entering the bloodstream your mental abilities will also decline³.
Lifestyle or personal habits that routinely expose a person to physical or mental stress, especially at an early age
Frequent absences from school can interrupt social development for children with chronic diseases

The panelists agreed that symptoms of EF decline or delay may be mistakenly attributed to a lack of motivation or willpower. Families should learn about executive mental functioning and help each child develop these skills from a young age. Dr. King suggested that primary care doctors should include questions about executive functioning (e.g. work or school performance, changes in social skills, or behavior) during medical exams to help track changes as time passes. This will help individuals and families know when to bring in additional support. She further mentioned that caregivers and patients should find potential sources of help before they notice a decline. The unpredictable nature of sickle cell favors those who prepare early. In a scientific study published in 2016, Dr. King’s team found that the quality and amount of parent-child interactions at home has a significant impact on mental development in affected children².

Any person’s executive functioning abilities can change during their lifetime. Sometimes these changes are short-lived and other times they can be permanent, as in the case of some stroke survivors. Here are some signs that you or your child may need additional support with executive functioning at work, school, or in the home^4,5:

More difficulty with adapting to change
Organized thinking becomes a challenge and more time is needed to answer questions
Difficulty planning or following step-by-step instructions
The person struggles to get back on track after an interruption when speaking or after a disruption to an activity
It is harder or takes longer to make decisions
Reduced ability to cope with existing challenges, including chronic or acute pain, or more intensely negative emotional responses than usual

EXECUTIVE FUNCTIONING IN EVERYDAY LIFE

The panelists agreed there are four critical times in life where executive mental functioning is important for anyone, and especially people living with a chronic health condition⁶. During these life stages, people with and without EF impairments need extra support:

In early childhood: This is when we learn how to process information from our surroundings, it is important for children to see EF modeled by family members and receive guidance and encouragement from family members. Children also need opportunities to learn and practice EF skills with other children.
When a young child enters school: Learning to excel within the structure of a school system requires self-regulation, planning, processing new information, and memory. Children diagnosed with an EF disorder need accommodations such as an Individualized Education Plan (IEP) or Section 504 Plan. These formal educational plans require involvement from a child’s pediatrician and her or his school or college to outline necessary classroom modifications⁷.
The transition from adolescence to adulthood: In addition to the universal challenges in this period, people living with sickle cell must use executive functioning to manage the medical aspects of their journey into adulthood. A successful transition requires extensive planning and organization skills.
In the workforce: EF and employability (the chances of getting and keeping a job) are closely linked. Adult sickle cell patients can struggle with employment or underemployment if they haven’t had enough practice advocating for their needs. Leadership relies heavily on planning and decision-making, improving the core aspects of mental executive functioning could enhance career advancement for anyone.

Right now researchers are still learning more about the molecular processes behind executive function decline. EF decline is often overlooked as a cause for some of the difficulties faced during the pediatric-to-adult clinic transition period. Yet, people living with sickle cell still have tools to defend against the effects of this complication. Currently, family involvement, school-related programs like IEP and 504 plans, and medical specialists can provide support to restore affected patients’ independence. Dr. King’s research shows that building a solid foundation of EF skills in early life can prevent or reduce the impact of this SCD complication. Remember, these skills can be improved over a lifetime, so it’s always the right time to get started!

HOW CAN YOU MAKE A DIFFERENCE?

The resources shown below can help individuals living with sickle cell disease, their caregivers, and their healthcare team to provide support for the executive function skill development.