Many survivors of childhood cancer experience long-term negative effects from their cancer treatments. About 500,000 childhood cancer survivors live in the USA, and about half of them report chronic health conditions. The most common chronic health condition reported is seizures.
Seizures are uncontrolled bursts of electrical activity in the brain that cause changes in behavior, movement, and feeling. Seizures can greatly affect brain development in those afflicted. For example, people who experience seizures also report problems remembering things and paying attention.
Scientists have shown medications used to treat seizures can reverse some of these issues in childhood cancer survivors. However, they’ve also discovered people who experience seizures generally have a lower quality of life and some lingering health risks, despite the success of these medications.
Researchers from St. Jude’s Children’s Hospital wanted to determine how seizures affect brain development, quality of life, and social well being in adults who survived childhood cancer. They compared childhood cancer survivors who currently have seizures with those who do not. People in both groups had received cancer treatments, so the researchers could focus on the effects of seizures independent of the effects of cancer treatments.
The scientists examined medical records from more than 2,000 people who were treated for childhood cancer at St. Jude’s Children’s Hospital. From the medical records they split the patients into two groups. These included one group of people who had a high frequency of seizures, meaning they previously had at least 3 seizures, and one group who had a lower frequency of seizures, meaning they had less than 3 seizures. The scientists further split these groups by the type of seizures and the overall number of anti-epileptic drugs they were taking.
Certified examiners performed neurological tests and questionnaires to gather information on each participant’s memory, attention span, and quality of life. The examiners used the Conners Continuous Performance Test to assess their attention spans, and the California Verbal Learning Test to assess their memories. They supplemented these with performance-based tests.
The researchers also administered questionnaires to the patients about their health and quality of life. The questions were split into categories including general health, vitality, body pain, and social function. They defined participants with a “reduced quality of life” as those with scores of 40 or less out of 100 on these questionnaires. The researchers also surveyed the participants’ social aspects like marital status, employment, education, and household income.
The scientists found childhood cancer survivors had low health-related quality of life in multiple areas. But those with seizures frequently also experienced negative long-term effects on memory, attention span, and quality of life, including a higher risk of unemployment.
The team concluded proper seizure treatment can improve childhood cancer survivors’ overall health. However, they acknowledged their study has limitations. In particular, their study lacked a control group of noncancer patients with seizures. They suggested future studies could use clinical trials and clinically-based seizure severity rating scales, rather than the data-driven approach they used.