Skeletal Muscle Changes, Function, and Health-Related Quality of Life in Survivors of Pediatric Critical Illness

Objectives: To describe functional and skeletal muscle changes observed during pediatric critical illness and recovery and their association with health-related quality of life.

Design: Prospective cohort study.

Setting: Single multidisciplinary PICU.

Patients: Children with greater than or equal to 1 organ dysfunction, expected PICU stay greater than or equal to 48 hours, expected survival to discharge, and without progressive neuromuscular disease or malignancies were followed from admission to approximately 6.7 months postdischarge.

Interventions: None.

Measurements and main results: Functional status was measured using the Functional Status Scale score and Pediatric Evaluation of Disability Inventory-Computer Adaptive Test. Patient and parental health-related quality of life were measured using the Pediatric Quality of Life Inventory and Short Form-36 questionnaires, respectively. Quadriceps muscle size, echogenicity, and fat thickness were measured using ultrasonography during PICU stay, at hospital discharge, and follow-up. Factors affecting change in muscle were explored. Associations between functional, muscle, and health-related quality of life changes were compared using regression analysis. Seventy-three survivors were recruited, of which 44 completed follow-ups. Functional impairment persisted in four of 44 (9.1%) at 6.7 months (interquartile range, 6-7.7 mo) after discharge. Muscle size decreased during PICU stay and was associated with inadequate energy intake (adjusted β, 0.15; 95% CI, 0.02-0.28; p = 0.030). No change in echogenicity or fat thickness was observed. Muscle growth postdischarge correlated with mobility function scores (adjusted β, 0.05; 95% CI, 0.01-0.09; p = 0.046). Improvements in mobility scores were associated with improved physical health-related quality of life at follow-up (adjusted β, 1.02; 95% CI, 0.23-1.81; p = 0.013). Child physical health-related quality of life at hospital discharge was associated with parental physical health-related quality of life (adjusted β, 0.09; 95% CI, 0.01-0.17; p = 0.027).

Conclusions: Muscle decreased in critically ill children, which was associated with energy inadequacy and impaired muscle growth postdischarge. Muscle changes correlated with change in mobility, which was associated with child health-related quality of life. Mobility, child health-related quality of life, and parental health-related quality of life appeared to be interlinked.