Conference Coverage

Childhood Hodgkin survivors have neurocognitive impairment



More than 2 decades on, adult survivors of childhood Hodgkin lymphoma report significantly more neurocognitive impairment than their siblings, but the differences may be related to risk factors in adulthood rather than to treatment in childhood, investigators say.

Among adults with a history of childhood Hodgkin lymphoma and their siblings as controls, the survivors reported significantly worse functioning than their brothers or sisters in four domains of neurocognitive functioning.

In multivariate analysis, however, while sex, race, activity level and smoking status were all significant predictors for worse neurocognitive impairment, there were no significant associations between chemotherapy drugs or chest radiation and neurocognitive impairment, said Annalynn M. Williams, PhD, from St. Jude Children’s Research Hospital in Memphis.

“Hodgkin lymphoma is the most common cancer diagnosed in adolescents, and for many years we’ve had high cure rates, resulting in a growing population of survivors who are now, unfortunately, at an increased risk for cardiovascular, respiratory, endocrine and neurologic late morbidity. The neurocognitive morbidity in this population, however, is unknown,” she said in oral abstract presented at the annual meeting of the American Society of Hematology.

Survivors and sibs

To better characterize the potential late neurocognitive effects of intensive Hodgkin lymphoma therapy in childhood, Dr. Williams and colleagues polled survivors of childhood Hodgkin lymphoma and randomly selected sibling controls who were participants in the Childhood Cancer Survivor Study (CCSS).

Participants were asked to complete questionnaires regarding four domains of neurocognitive impairment: task efficiency, emotional regulation, organization, and memory. The investigators defined impairment in each domain as a score lower than that of the 90th percentile of community controls from the St. Jude Lifetime Cohort.

A total of 1,564 survivors and 725 controls completed the questionnaires and were included in the study.

The median age at follow-up was slightly higher among survivors, at 37 versus 32 years. The median age at diagnosis was 14, and the median time since diagnosis was 23 years.

In all, 10.8% of survivors reported impaired task efficiency, compared with 7.7% of controls. Problems with emotional regulation were reported by 16.6% of survivors versus 11.5% of siblings, and difficulties with organization and memory were reported by 12.1% versus10.3%, and 8.1% versus 5.7%, respectively.

In a model adjusted for age, sex, and race, the relative risks for neurocognitive impairment among survivors versus siblings, were as follows: task efficiency (RR,1.37); emotional regulation (RR, 1.56); organization (RR, 1.32); memory (RR, 1.72) (all significant by confidence interval).

In a model adjusted for sex, race, smoking status, exercise, age, time since diagnosis, and treatment exposures, risk factors for neurocognitive impairment among survivors included female versus male sex (significant for emotional regulation and memory deficits); non-White versus White (significant for task efficiency); former smoker versus never (significant for all domains except organization); current smoker versus never (significant for task efficiency and emotional regulation); and meeting Centers for Disease Control and Prevention exercise criteria versus not (negatively significant for task efficiency and organization); (P < .05 for all above comparisons).

However, in a model adjusted for relapse, second malignancy, treatment exposures, age, sex, race, time since diagnosis, smoking status and physical activity, only relapse or second malignancy – surrogates for additional treatment exposures – were significantly associated with neurocognitive impairment, and then only in the domain of task efficiency.

Chronic conditions significantly associated with risk for impairment included cardiovascular disease (significant across all domains), respiratory comorbidities (significant for task efficiency), endocrine disorders (significant for task efficiency), and neurologic disorders (significant in all domains except organization).

“While these analyses give us a sense of the presence of neurocognitive impairment in a large sample of Hodgkin lymphoma survivors from across the U.S., these analyses are limited by the self-reported nature of the data,” Dr. Williams acknowledged.

“Because survivors self-report impairments, these likely represent overt, symptomatic neurocognitive impairments. Many more survivors may experience more subtle neurocognitive impairments, and additional research with objective measures of both chronic health conditions and neurocognitive functioning are warranted,” she added.


Recommended Reading

Pembrolizumab, nivolumab linked to 3% rate of neurologic events
MDedge Neurology
Is pain or dependency driving elevated opioid use among long-term cancer survivors?
MDedge Neurology