Symptom Trajectories in Children Receiving Treatment for Leukemia: A Latent Class Growth Analysis With Multitrajectory Modeling

Abstract

Context: Cancer treatment symptoms play a major role in determining the health of children with cancer. Symptom toxicity often results in complications, treatment delays, and therapy dose reductions that can compromise leukemia therapy and jeopardize chances for long-term survival. Critical to understanding symptom experiences during treatment is the need for exploration of "why" inter-individual symptom differences occur; this will determine who may be most susceptible to treatment toxicities.

Objectives: This study examined specific symptom trajectories during the first 18 months of childhood leukemia treatment. Symptom measures included fatigue, sleep disturbances, pain, nausea, and depression.

Methods: Symptom trajectories of 236 children with leukemia three to 18 years old were explored prospectively over four periods: initiation of post-induction therapy, four and eight post-induction therapy, and the last time point was at the beginning of maintenance/continuation therapy. Latent class growth analysis was used to classify patients into distinctive groups with similar symptom trajectories based on patients' response patterns on the symptom measures over time.

Results: Three latent classes of symptom trajectories were identified and classified into mild, moderate, and severe symptom trajectories. The only demographic characteristic with a significant relationship to membership in the latent class symptom trajectories was race/ethnicity. All other demographic characteristics including leukemia risk levels showed no significant relationships.

Conclusion: This study is unique in that groups of patients with similar symptoms were identified rather than groups of symptoms. Further research using latent class growth analysis is needed.

Keywords: Symptom trajectories; childhood leukemia; latent class growth analysis; leukemia therapy; treatment toxicities.

Figure 1.

Conceptual Framework

Figure 2.

Latent classes of symptom trajectories with 95% CIs (dashed lines) by symptom measures. Patients (group 1, n₁ = 84, 36.6%) experiencing mild symptoms. Patients (group 2, n₂ = 127, 52.2%) experiencing moderate symptoms. Patients (group 3, n₃ = 25, 11.1%) experiencing severe symptoms.

Figure 3.

Odds Ratios with 95%CIs of Experiencing More Severe Symptoms by Demographic Characteristics and Leukemia Risk Levels