Association of anthropometric z score with complications and length of hospital stay in children with severe pneumonia aged 3 months to 5 years

Background: Severe pneumonia in children accounts for a significant healthcare burden, involving prolonged hospitalization and increased risk of complications. The prognosis is closely related to the child's nutrition status. Anthropometric z scores are preferred to evaluate growth levels in children. This study aimed to investigate the association of anthropometric z scores with complications and length of hospital stay (LOS) in children with severe pneumonia. Methods: This study included 361 hospitalized children aged 3 months to 5 years with severe pneumonia in Tianjin, China. Anthropometry was performed, and anthropometric z scores were calculated. Blood laboratory indices were assessed, and complications and LOS were recorded. Results: The average anthropometric z scores were -0.10 +/- 1.15 (body mass index for age z score), 0.00 +/- 0.97 (upper arm circumference for age z score [ACAZ]), and -0.14 +/- 1.00 (triceps skinfold thickness for age z score [TSAZ]). The prevalence of complications was 73.96% (n = 267), including 82 children with only respiratory complications, 71 with only extrapulmonary complications, and 114 with both. After adjusting for confounding factors, compared with the noncomplication group, only the extrapulmonary complication group had a lower TSAZ (odds ratio [OR] = 0.597; 95% CI = 0.405-0.880; P < 0.05), whereas the respiratory and extrapulmonary complication group had a lower ACAZ (OR = 0.674; 95% CI = 0.469-0.969; P < 0.05) and TSAZ (OR = 0.573; 95% CI = 0.389-0.843; P < 0.05). ACAZ (beta = -0.368; 95% CI = -0.720 to 0.016; P < 0.05) and TSAZ (beta = -1.123; 95% CI = -1.470 to -0.777; P < 0.05) were negatively correlated with LOS. Conclusion: ACAZ and TSAZ were associated with complications and LOS of severe pneumonia in children aged 3 months to 5 years.